Constructive role of replication crises teaches a lot about 1.) Non-fallacious uses of statistical tests, 2.) Rationale for the role of probability in tests, 3.) How to reformulate tests.
D. Mayo: Philosophy of Statistics & the Replication Crisis in Sciencejemille6
D. Mayo discusses various disputes-notably the replication crisis in science-in the context of her just released book: Statistical Inference as Severe Testing: How to Get Beyond the Statistics Wars.
Mayo: Evidence as Passing a Severe Test (How it Gets You Beyond the Statistic...jemille6
D. G. Mayo April 28, 2021 presentation to the CUNY Graduate Center Philosophy Colloquium "Evidence as Passing a Severe Test (How it Gets You Beyond the Statistics Wars)"
Replication Crises and the Statistics Wars: Hidden Controversiesjemille6
D. Mayo presentation at the X-Phil conference on "Reproducibility and Replicabililty in Psychology and Experimental Philosophy", University College London (June 14, 2018)
D. G. Mayo: Your data-driven claims must still be probed severelyjemille6
In the session "Philosophy of Science and the New Paradigm of Data-Driven Science at the American Statistical Association Conference on Statistical Learning and Data Science/Nonparametric Statistics
Severe Testing: The Key to Error Correctionjemille6
D. G. Mayo's slides for her presentation given March 17, 2017 at Boston Colloquium for Philosophy of Science, Alfred I.Taub forum: "Understanding Reproducibility & Error Correction in Science"
Probing with Severity: Beyond Bayesian Probabilism and Frequentist Performancejemille6
Slides from Rutgers Seminar talk by Deborah G Mayo
December 3, 2014
Rutgers, Department of Statistics and Biostatistics
Abstract: Getting beyond today’s most pressing controversies revolving around statistical methods, I argue, requires scrutinizing their underlying statistical philosophies.Two main philosophies about the roles of probability in statistical inference are probabilism and performance (in the long-run). The first assumes that we need a method of assigning probabilities to hypotheses; the second assumes that the main function of statistical method is to control long-run performance. I offer a third goal: controlling and evaluating the probativeness of methods. An inductive inference, in this conception, takes the form of inferring hypotheses to the extent that they have been well or severely tested. A report of poorly tested claims must also be part of an adequate inference. I develop a statistical philosophy in which error probabilities of methods may be used to evaluate and control the stringency or severity of tests. I then show how the “severe testing” philosophy clarifies and avoids familiar criticisms and abuses of significance tests and cognate methods (e.g., confidence intervals). Severity may be threatened in three main ways: fallacies of statistical tests, unwarranted links between statistical and substantive claims, and violations of model assumptions.
D. Mayo: Philosophy of Statistics & the Replication Crisis in Sciencejemille6
D. Mayo discusses various disputes-notably the replication crisis in science-in the context of her just released book: Statistical Inference as Severe Testing: How to Get Beyond the Statistics Wars.
Mayo: Evidence as Passing a Severe Test (How it Gets You Beyond the Statistic...jemille6
D. G. Mayo April 28, 2021 presentation to the CUNY Graduate Center Philosophy Colloquium "Evidence as Passing a Severe Test (How it Gets You Beyond the Statistics Wars)"
Replication Crises and the Statistics Wars: Hidden Controversiesjemille6
D. Mayo presentation at the X-Phil conference on "Reproducibility and Replicabililty in Psychology and Experimental Philosophy", University College London (June 14, 2018)
D. G. Mayo: Your data-driven claims must still be probed severelyjemille6
In the session "Philosophy of Science and the New Paradigm of Data-Driven Science at the American Statistical Association Conference on Statistical Learning and Data Science/Nonparametric Statistics
Severe Testing: The Key to Error Correctionjemille6
D. G. Mayo's slides for her presentation given March 17, 2017 at Boston Colloquium for Philosophy of Science, Alfred I.Taub forum: "Understanding Reproducibility & Error Correction in Science"
Probing with Severity: Beyond Bayesian Probabilism and Frequentist Performancejemille6
Slides from Rutgers Seminar talk by Deborah G Mayo
December 3, 2014
Rutgers, Department of Statistics and Biostatistics
Abstract: Getting beyond today’s most pressing controversies revolving around statistical methods, I argue, requires scrutinizing their underlying statistical philosophies.Two main philosophies about the roles of probability in statistical inference are probabilism and performance (in the long-run). The first assumes that we need a method of assigning probabilities to hypotheses; the second assumes that the main function of statistical method is to control long-run performance. I offer a third goal: controlling and evaluating the probativeness of methods. An inductive inference, in this conception, takes the form of inferring hypotheses to the extent that they have been well or severely tested. A report of poorly tested claims must also be part of an adequate inference. I develop a statistical philosophy in which error probabilities of methods may be used to evaluate and control the stringency or severity of tests. I then show how the “severe testing” philosophy clarifies and avoids familiar criticisms and abuses of significance tests and cognate methods (e.g., confidence intervals). Severity may be threatened in three main ways: fallacies of statistical tests, unwarranted links between statistical and substantive claims, and violations of model assumptions.
Today we’ll try to cover a number of things:
1. Learning philosophy/philosophy of statistics
2. Situating the broad issues within philosophy of science
3. Little bit of logic
4. Probability and random variables
Fusion Confusion? Comments on Nancy Reid: "BFF Four-Are we Converging?"jemille6
D. Mayo's comments on Nancy Reid's "BFF Four-Are we Converging?" given May 2, 2017 at The Fourth Bayesian, Fiducial and Frequentists Workshop held at Harvard University.
Controversy Over the Significance Test Controversyjemille6
Deborah Mayo (Professor of Philosophy, Virginia Tech, Blacksburg, Virginia) in PSA 2016 Symposium: Philosophy of Statistics in the Age of Big Data and Replication Crises
D. G. Mayo (Virginia Tech) "Error Statistical Control: Forfeit at your Peril" presented May 23 at the session on "The Philosophy of Statistics: Bayesianism, Frequentism and the Nature of Inference," 2015 APS Annual Convention in NYC.
Surrogate Science: How Fisher, Neyman-Pearson, and Bayes Were Transformed int...jemille6
Gerd Gigerenzer (Director of Max Planck Institute for Human Development, Berlin, Germany) in the PSA 2016 Symposium:Philosophy of Statistics in the Age of Big Data and Replication Crises
D. Mayo: Putting the brakes on the breakthrough: An informal look at the argu...jemille6
“Putting the Brakes on the Breakthrough, or ‘How I used simple logic to uncover a flaw in a controversial 50-year old ‘theorem’ in statistical foundations taken as a‘breakthrough’ in favor of Bayesian vs frequentist error statistics’”
Deborah G. Mayo: Is the Philosophy of Probabilism an Obstacle to Statistical Fraud Busting?
Presentation slides for: Revisiting the Foundations of Statistics in the Era of Big Data: Scaling Up to Meet the Challenge[*] at the Boston Colloquium for Philosophy of Science (Feb 21, 2014).
D. Mayo: Philosophical Interventions in the Statistics Warsjemille6
ABSTRACT: While statistics has a long history of passionate philosophical controversy, the last decade especially cries out for philosophical illumination. Misuses of statistics, Big Data dredging, and P-hacking make it easy to find statistically significant, but spurious, effects. This obstructs a test's ability to control the probability of erroneously inferring effects–i.e., to control error probabilities. Disagreements about statistical reforms reflect philosophical disagreements about the nature of statistical inference–including whether error probability control even matters! I describe my interventions in statistics in relation to three events. (1) In 2016 the American Statistical Association (ASA) met to craft principles for avoiding misinterpreting P-values. (2) In 2017, a "megateam" (including philosophers of science) proposed "redefining statistical significance," replacing the common threshold of P ≤ .05 with P ≤ .005. (3) In 2019, an editorial in the main ASA journal called for abandoning all P-value thresholds, and even the words "significant/significance".
A word on each. (1) Invited to be a "philosophical observer" at their meeting, I found the major issues were conceptual. P-values measure how incompatible data are from what is expected under a hypothesis that there is no genuine effect: the smaller the P-value, the more indication of incompatibility. The ASA list of familiar misinterpretations–P-values are not posterior probabilities, statistical significance is not substantive importance, no evidence against a hypothesis need not be evidence for it–I argue, should not be the basis for replacing tests with methods less able to assess and control erroneous interpretations of data. (Mayo 2016, 2019). (2) The "redefine statistical significance" movement appraises P-values from the perspective of a very different quantity: a comparative Bayes Factor. Failing to recognize how contrasting approaches measure different things, disputants often talk past each other (Mayo 2018). (3) To ban P-value thresholds, even to distinguish terrible from warranted evidence, I say, is a mistake (2019). It will not eradicate P-hacking, but it will make it harder to hold P-hackers accountable. A 2020 ASA Task Force on significance testing has just been announced. (I would like to think my blog errorstatistics.com helped.)
To enter the fray between rival statistical approaches, it helps to have a principle applicable to all accounts. There's poor evidence for a claim if little if anything has been done to find it flawed even if it is. This forms a basic requirement for evidence I call the severity requirement. A claim passes with severity only if it is subjected to and passes a test that probably would have found it flawed, if it were. It stems from Popper, though he never adequately cashed it out. A variant is the frequentist principle of evidence developed with Sir David Cox (Mayo and Cox 20
Byrd statistical considerations of the histomorphometric test protocol (1)jemille6
"Statistical considerations of the histomorphometric test protocol"
John E. Byrd, Ph.D. D-ABFA
Maria-Teresa Tersigni-Tarrant, Ph.D.
Central Identification Laboratory
JPAC
A. Gelman "50 shades of gray: A research story," presented May 23 at the session on "The Philosophy of Statistics: Bayesianism, Frequentism and the Nature of Inference," 2015 APS Annual Convention in NYC.
Abstract: Mounting failures of replication in the social and biological sciences give a practical spin to statistical foundations in the form of the question: How can we attain reliability when methods make illicit cherry-picking and significance seeking so easy? Researchers, professional societies, and journals are increasingly getting serious about methodological reforms to restore scientific integrity – some are quite welcome (e.g., pre-registration), while others are quite radical. The American Statistical Association convened members from differing tribes of frequentists, Bayesians, and likelihoodists to codify misuses of P-values. Largely overlooked are the philosophical presuppositions of both criticisms and proposed reforms. Paradoxically, alternative replacement methods may enable rather than reveal illicit inferences due to cherry-picking, multiple testing, and other biasing selection effects. Crowd-sourced reproducibility research in psychology is helping to change the reward structure but has its own shortcomings. Focusing on purely statistical considerations, it tends to overlook problems with artificial experiments. Without a better understanding of the philosophical issues, we can expect the latest reforms to fail.
D. Mayo: Replication Research Under an Error Statistical Philosophy jemille6
D. Mayo (Virginia Tech) slides from her talk June 3 at the "Preconference Workshop on Replication in the Sciences" at the 2015 Society for Philosophy and Psychology meeting.
Stephen Senn slides:"‘Repligate’: reproducibility in statistical studies. What does it mean and in what sense does it matter?" presented May 23 at the session on "The Philosophy of Statistics: Bayesianism, Frequentism and the Nature of Inference"," at the 2015 APS Annual Convention in NYC
“The importance of philosophy of science for statistical science and vice versa”jemille6
My paper “The importance of philosophy of science for statistical science and vice
versa” presented (zoom) at the conference: IS PHILOSOPHY USEFUL FOR SCIENCE, AND/OR VICE VERSA? January 30 - February 2, 2024 at Chapman University, Schmid College of Science and Technology.
Today we’ll try to cover a number of things:
1. Learning philosophy/philosophy of statistics
2. Situating the broad issues within philosophy of science
3. Little bit of logic
4. Probability and random variables
Fusion Confusion? Comments on Nancy Reid: "BFF Four-Are we Converging?"jemille6
D. Mayo's comments on Nancy Reid's "BFF Four-Are we Converging?" given May 2, 2017 at The Fourth Bayesian, Fiducial and Frequentists Workshop held at Harvard University.
Controversy Over the Significance Test Controversyjemille6
Deborah Mayo (Professor of Philosophy, Virginia Tech, Blacksburg, Virginia) in PSA 2016 Symposium: Philosophy of Statistics in the Age of Big Data and Replication Crises
D. G. Mayo (Virginia Tech) "Error Statistical Control: Forfeit at your Peril" presented May 23 at the session on "The Philosophy of Statistics: Bayesianism, Frequentism and the Nature of Inference," 2015 APS Annual Convention in NYC.
Surrogate Science: How Fisher, Neyman-Pearson, and Bayes Were Transformed int...jemille6
Gerd Gigerenzer (Director of Max Planck Institute for Human Development, Berlin, Germany) in the PSA 2016 Symposium:Philosophy of Statistics in the Age of Big Data and Replication Crises
D. Mayo: Putting the brakes on the breakthrough: An informal look at the argu...jemille6
“Putting the Brakes on the Breakthrough, or ‘How I used simple logic to uncover a flaw in a controversial 50-year old ‘theorem’ in statistical foundations taken as a‘breakthrough’ in favor of Bayesian vs frequentist error statistics’”
Deborah G. Mayo: Is the Philosophy of Probabilism an Obstacle to Statistical Fraud Busting?
Presentation slides for: Revisiting the Foundations of Statistics in the Era of Big Data: Scaling Up to Meet the Challenge[*] at the Boston Colloquium for Philosophy of Science (Feb 21, 2014).
D. Mayo: Philosophical Interventions in the Statistics Warsjemille6
ABSTRACT: While statistics has a long history of passionate philosophical controversy, the last decade especially cries out for philosophical illumination. Misuses of statistics, Big Data dredging, and P-hacking make it easy to find statistically significant, but spurious, effects. This obstructs a test's ability to control the probability of erroneously inferring effects–i.e., to control error probabilities. Disagreements about statistical reforms reflect philosophical disagreements about the nature of statistical inference–including whether error probability control even matters! I describe my interventions in statistics in relation to three events. (1) In 2016 the American Statistical Association (ASA) met to craft principles for avoiding misinterpreting P-values. (2) In 2017, a "megateam" (including philosophers of science) proposed "redefining statistical significance," replacing the common threshold of P ≤ .05 with P ≤ .005. (3) In 2019, an editorial in the main ASA journal called for abandoning all P-value thresholds, and even the words "significant/significance".
A word on each. (1) Invited to be a "philosophical observer" at their meeting, I found the major issues were conceptual. P-values measure how incompatible data are from what is expected under a hypothesis that there is no genuine effect: the smaller the P-value, the more indication of incompatibility. The ASA list of familiar misinterpretations–P-values are not posterior probabilities, statistical significance is not substantive importance, no evidence against a hypothesis need not be evidence for it–I argue, should not be the basis for replacing tests with methods less able to assess and control erroneous interpretations of data. (Mayo 2016, 2019). (2) The "redefine statistical significance" movement appraises P-values from the perspective of a very different quantity: a comparative Bayes Factor. Failing to recognize how contrasting approaches measure different things, disputants often talk past each other (Mayo 2018). (3) To ban P-value thresholds, even to distinguish terrible from warranted evidence, I say, is a mistake (2019). It will not eradicate P-hacking, but it will make it harder to hold P-hackers accountable. A 2020 ASA Task Force on significance testing has just been announced. (I would like to think my blog errorstatistics.com helped.)
To enter the fray between rival statistical approaches, it helps to have a principle applicable to all accounts. There's poor evidence for a claim if little if anything has been done to find it flawed even if it is. This forms a basic requirement for evidence I call the severity requirement. A claim passes with severity only if it is subjected to and passes a test that probably would have found it flawed, if it were. It stems from Popper, though he never adequately cashed it out. A variant is the frequentist principle of evidence developed with Sir David Cox (Mayo and Cox 20
Byrd statistical considerations of the histomorphometric test protocol (1)jemille6
"Statistical considerations of the histomorphometric test protocol"
John E. Byrd, Ph.D. D-ABFA
Maria-Teresa Tersigni-Tarrant, Ph.D.
Central Identification Laboratory
JPAC
A. Gelman "50 shades of gray: A research story," presented May 23 at the session on "The Philosophy of Statistics: Bayesianism, Frequentism and the Nature of Inference," 2015 APS Annual Convention in NYC.
Abstract: Mounting failures of replication in the social and biological sciences give a practical spin to statistical foundations in the form of the question: How can we attain reliability when methods make illicit cherry-picking and significance seeking so easy? Researchers, professional societies, and journals are increasingly getting serious about methodological reforms to restore scientific integrity – some are quite welcome (e.g., pre-registration), while others are quite radical. The American Statistical Association convened members from differing tribes of frequentists, Bayesians, and likelihoodists to codify misuses of P-values. Largely overlooked are the philosophical presuppositions of both criticisms and proposed reforms. Paradoxically, alternative replacement methods may enable rather than reveal illicit inferences due to cherry-picking, multiple testing, and other biasing selection effects. Crowd-sourced reproducibility research in psychology is helping to change the reward structure but has its own shortcomings. Focusing on purely statistical considerations, it tends to overlook problems with artificial experiments. Without a better understanding of the philosophical issues, we can expect the latest reforms to fail.
D. Mayo: Replication Research Under an Error Statistical Philosophy jemille6
D. Mayo (Virginia Tech) slides from her talk June 3 at the "Preconference Workshop on Replication in the Sciences" at the 2015 Society for Philosophy and Psychology meeting.
Stephen Senn slides:"‘Repligate’: reproducibility in statistical studies. What does it mean and in what sense does it matter?" presented May 23 at the session on "The Philosophy of Statistics: Bayesianism, Frequentism and the Nature of Inference"," at the 2015 APS Annual Convention in NYC
“The importance of philosophy of science for statistical science and vice versa”jemille6
My paper “The importance of philosophy of science for statistical science and vice
versa” presented (zoom) at the conference: IS PHILOSOPHY USEFUL FOR SCIENCE, AND/OR VICE VERSA? January 30 - February 2, 2024 at Chapman University, Schmid College of Science and Technology.
Statistical Inference as Severe Testing: Beyond Performance and Probabilismjemille6
A talk given by Deborah G Mayo
(Dept of Philosophy, Virginia Tech) to the Seminar in Advanced Research Methods at the Dept of Psychology, Princeton University on
November 14, 2023
TITLE: Statistical Inference as Severe Testing: Beyond Probabilism and Performance
ABSTRACT: I develop a statistical philosophy in which error probabilities of methods may be used to evaluate and control the stringency or severity of tests. A claim is severely tested to the extent it has been subjected to and passes a test that probably would have found flaws, were they present. The severe-testing requirement leads to reformulating statistical significance tests to avoid familiar criticisms and abuses. While high-profile failures of replication in the social and biological sciences stem from biasing selection effects—data dredging, multiple testing, optional stopping—some reforms and proposed alternatives to statistical significance tests conflict with the error control that is required to satisfy severity. I discuss recent arguments to redefine, abandon, or replace statistical significance.
The Statistics Wars: Errors and Casualtiesjemille6
ABSTRACT: Mounting failures of replication in the social and biological sciences give a new urgency to critically appraising proposed statistical reforms. While many reforms are welcome (preregistration of experiments, replication, discouraging cookbook uses of statistics), there have been casualties. The philosophical presuppositions behind the meta-research battles remain largely hidden. Too often the statistics wars have become proxy wars between competing tribe leaders, each keen to advance one or another tool or school, rather than build on efforts to do better science. Efforts of replication researchers and open science advocates are diminished when so much attention is centered on repeating hackneyed howlers of statistical significance tests (statistical significance isn’t substantive significance, no evidence against isn’t evidence for), when erroneous understanding of basic statistical terms goes uncorrected, and when bandwagon effects lead to popular reforms that downplay the importance of error probability control. These casualties threaten our ability to hold accountable the “experts,” the agencies, and all the data handlers increasingly exerting power over our lives.
High-profile failures of replication in the social and biological sciences underwrite a
minimal requirement of evidence: If little or nothing has been done to rule out flaws in
inferring a claim, then it has not passed a severe test. A claim is severely tested to the
extent it has been subjected to and passes a test that probably would have found flaws,
were they present. This probability is the severity with which a claim has passed. The
goal of highly well-tested claims differs from that of highly probable ones, explaining
why experts so often disagree about statistical reforms. Even where today’s statistical
test critics see themselves as merely objecting to misuses and misinterpretations, the
reforms they recommend often grow out of presuppositions about the role of probability
in inductive-statistical inference. Paradoxically, I will argue, some of the reforms
intended to replace or improve on statistical significance tests enable rather than reveal
illicit inferences due to cherry-picking, multiple testing, and data-dredging. Some
preclude testing and falsifying claims altogether. These are the “casualties” on which I
will focus. I will consider Fisherian vs Neyman-Pearson tests, Bayes factors, Bayesian
posteriors, likelihoodist assessments, and the “screening model” of tests (a quasiBayesian-frequentist assessment). Whether one accepts this philosophy of evidence, I
argue, that it provides a standpoint for avoiding both the fallacies of statistical testing
and the casualties of today’s statistics wars.
The Statistics Wars and Their Causalities (refs)jemille6
High-profile failures of replication in the social and biological sciences underwrite a
minimal requirement of evidence: If little or nothing has been done to rule out flaws in inferring a claim, then it has not passed a severe test. A claim is severely tested to the extent it has been subjected to and passes a test that probably would have found flaws, were they present. This probability is the severity with which a claim has passed. The goal of highly well-tested claims differs from that of highly probable ones, explaining why experts so often disagree about statistical reforms. Even where today’s statistical test critics see themselves as merely objecting to misuses and misinterpretations, the reforms they recommend often grow out of presuppositions about the role of probability in inductive-statistical inference. Paradoxically, I will argue, some of the reforms intended to replace or improve on statistical significance tests enable rather than reveal illicit inferences due to cherry-picking, multiple testing, and data-dredging. Some preclude testing and falsifying claims altogether. These are the “casualties” on which I will focus. I will consider Fisherian vs Neyman-Pearson tests, Bayes factors, Bayesian posteriors, likelihoodist assessments, and the “screening model” of tests (a quasiBayesian-frequentist assessment). Whether one accepts this philosophy of evidence, I argue, that it provides a standpoint for avoiding both the fallacies of statistical testing and the casualties of today’s statistics wars.
The Statistics Wars and Their Casualties (w/refs)jemille6
High-profile failures of replication in the social and biological sciences underwrite a minimal requirement of evidence: If little or nothing has been done to rule out flaws in inferring a claim, then it has not passed a severe test. A claim is severely tested to the extent it has been subjected to and passes a test that probably would have found flaws, were they present. This probability is the severity with which a claim has passed. The goal of highly well-tested claims differs from that of highly probable ones, explaining why experts so often disagree about statistical reforms. Even where today’s statistical test critics see themselves as merely objecting to misuses and misinterpretations, the reforms they recommend often grow out of presuppositions about the role of probability in inductive-statistical inference. Paradoxically, I will argue, some of the reforms intended to replace or improve on statistical significance tests enable rather than reveal illicit inferences due to cherry-picking, multiple testing, and data-dredging. Some preclude testing and falsifying claims altogether. These are the “casualties” on which I will focus. I will consider Fisherian vs Neyman-Pearson tests, Bayes factors, Bayesian posteriors, likelihoodist assessments, and the “screening model” of tests (a quasi-Bayesian-frequentist assessment). Whether one accepts this philosophy of evidence, I argue, that it provides a standpoint for avoiding both the fallacies of statistical testing and the casualties of today’s statistics wars.
"The Statistical Replication Crisis: Paradoxes and Scapegoats”jemille6
D. G. Mayo LSE Popper talk, May 10, 2016.
Abstract: Mounting failures of replication in the social and biological sciences give a practical spin to statistical foundations in the form of the question: How can we attain reliability when Big Data methods make illicit cherry-picking and significance seeking so easy? Researchers, professional societies, and journals are increasingly getting serious about methodological reforms to restore scientific integrity – some are quite welcome (e.g., preregistration), while others are quite radical. Recently, the American Statistical Association convened members from differing tribes of frequentists, Bayesians, and likelihoodists to codify misuses of P-values. Largely overlooked are the philosophical presuppositions of both criticisms and proposed reforms. Paradoxically, alternative replacement methods may enable rather than reveal illicit inferences due to cherry-picking, multiple testing, and other biasing selection effects. Popular appeals to “diagnostic testing” that aim to improve replication rates may (unintentionally) permit the howlers and cookbook statistics we are at pains to root out. Without a better understanding of the philosophical issues, we can expect the latest reforms to fail.
Slides given for Deborah G. Mayo talk at Minnesota Center for Philosophy of Science at University of Minnesota on the ASA 2016 statement on P-values and Error Statistics
Paper given at PSA 22 Symposium: Multiplicity, Data-Dredging and Error Control
MAYO ABSTRACT: I put forward a general principle for evidence: an error-prone claim C is warranted to the extent it has been subjected to, and passes, an analysis that very probably would have found evidence of flaws in C just if they are present. This probability is the severity with which C has passed the test. When a test’s error probabilities quantify the capacity of tests to probe errors in C, I argue, they can be used to assess what has been learned from the data about C. A claim can be probable or even known to be true, yet poorly probed by the data and model at hand. The severe testing account leads to a reformulation of statistical significance tests: Moving away from a binary interpretation, we test several discrepancies from any reference hypothesis and report those well or poorly warranted. A probative test will generally involve combining several subsidiary tests, deliberately designed to unearth different flaws. The approach relates to confidence interval estimation, but, like confidence distributions (CD) (Thornton), a series of different confidence levels is considered. A 95% confidence interval method, say using the mean M of a random sample to estimate the population mean μ of a Normal distribution, will cover the true, but unknown, value of μ 95% of the time in a hypothetical series of applications. However, we cannot take .95 as the probability that a particular interval estimate (a ≤ μ ≤ b) is correct—at least not without a prior probability to μ. In the severity interpretation I propose, we can nevertheless give an inferential construal post-data, while still regarding μ as fixed. For example, there is good evidence μ ≥ a (the lower estimation limit) because if μ < a, then with high probability .95 (or .975 if viewed as one-sided) we would have observed a smaller value of M than we did. Likewise for inferring μ ≤ b. To understand a method’s capability to probe flaws in the case at hand, we cannot just consider the observed data, unlike in strict Bayesian accounts. We need to consider what the method would have inferred if other data had been observed. For each point μ’ in the interval, we assess how severely the claim μ > μ’ has been probed. I apply the severity account to the problems discussed by earlier speakers in our session. The problem with multiple testing (and selective reporting) when attempting to distinguish genuine effects from noise, is not merely that it would, if regularly applied, lead to inferences that were often wrong. Rather, it renders the method incapable, or practically so, of probing the relevant mistaken inference in the case at hand. In other cases, by contrast, (e.g., DNA matching) the searching can increase the test’s probative capacity. In this way the severe testing account can explain competing intuitions about multiplicity and data-dredging, while blocking inferences based on problematic data-dredging
Hypothesis Testing is a kind of data testing used in marketing research.
It helps you to test the give data to gain proper insights about it.
Check errors if there and rectify it.
D. Mayo (Dept of Philosophy, VT)
Sir David Cox’s Statistical Philosophy and Its Relevance to Today’s Statistical Controversies
ABSTRACT: This talk will explain Sir David Cox's views of the nature and importance of statistical foundations and their relevance to today's controversies about statistical inference, particularly in using statistical significance testing and confidence intervals. Two key themes of Cox's statistical philosophy are: first, the importance of calibrating methods by considering their behavior in (actual or hypothetical) repeated sampling, and second, ensuring the calibration is relevant to the specific data and inquiry. A question that arises is: How can the frequentist calibration provide a genuinely epistemic assessment of what is learned from data? Building on our jointly written papers, Mayo and Cox (2006) and Cox and Mayo (2010), I will argue that relevant error probabilities may serve to assess how well-corroborated or severely tested statistical claims are.
Nancy Reid, Dept. of Statistics, University of Toronto. Inaugural receiptant of the "David R. Cox Foundations of Statistics Award".
Slides from Invited presentation at 2023 JSM: “The Importance of Foundations in Statistical Science“
Ronald Wasserstein, Chair (American Statistical Association)
ABSTRACT: David Cox wrote “A healthy interplay between theory and application is crucial for statistics… This is particularly the case when by theory we mean foundations of statistical analysis, rather than the theoretical analysis of specific statistical methods.” These foundations distinguish statistical science from the many fields of research in which statistical thinking is a key intellectual component. In this talk I will emphasize the ongoing importance and relevance of theoretical advances and theoretical thinking through some illustrative examples.
Errors of the Error Gatekeepers: The case of Statistical Significance 2016-2022jemille6
ABSTRACT: Statistical significance tests serve in gatekeeping against being fooled by randomness, but recent attempts to gatekeep these tools have themselves malfunctioned. Warranted gatekeepers formulate statistical tests so as to avoid fallacies and misuses of P-values. They highlight how multiplicity, optional stopping, and data-dredging can readily invalidate error probabilities. It is unwarranted, however, to argue that statistical significance and P-value thresholds be abandoned because they can be misused. Nor is it warranted to argue for abandoning statistical significance based on presuppositions about evidence and probability that are at odds with those underlying statistical significance tests. When statistical gatekeeping malfunctions, I argue, it undermines a central role to which scientists look to statistics. In order to combat the dangers of unthinking, bandwagon effects, statistical practitioners and consumers need to be in a position to critically evaluate the ramifications of proposed "reforms” (“stat activism”). I analyze what may be learned from three recent episodes of gatekeeping (and meta-gatekeeping) at the American Statistical Association (ASA).
Causal inference is not statistical inferencejemille6
Jon Williamson (University of Kent)
ABSTRACT: Many methods for testing causal claims are couched as statistical methods: e.g.,
randomised controlled trials, various kinds of observational study, meta-analysis, and
model-based approaches such as structural equation modelling and graphical causal
modelling. I argue that this is a mistake: causal inference is not a purely statistical
problem. When we look at causal inference from a general point of view, we see that
methods for causal inference fit into the framework of Evidential Pluralism: causal
inference is properly understood as requiring mechanistic inference in addition to
statistical inference.
Evidential Pluralism also offers a new perspective on the replication crisis. That
observed associations are not replicated by subsequent studies is a part of normal
science. A problem only arises when those associations are taken to establish causal
claims: a science whose established causal claims are constantly overturned is indeed
in crisis. However, if we understand causal inference as involving mechanistic inference
alongside statistical inference, as Evidential Pluralism suggests, we avoid fallacious
inferences from association to causation. Thus, Evidential Pluralism offers the means to
prevent the drama of science from turning into a crisis.
Stephan Guttinger (Lecturer in Philosophy of Data/Data Ethics, University of Exeter, UK)
ABSTRACT: The idea of “questionable research practices” (QRPs) is central to the narrative of a replication crisis in the experimental sciences. According to this narrative the low replicability of scientific findings is not simply due to fraud or incompetence, but in large part to the widespread use of QRPs, such as “p-hacking” or the lack of adequate experimental controls. The claim is that such flawed practices generate flawed output. The reduction – or even elimination – of QRPs is therefore one of the main strategies proposed by policymakers and scientists to tackle the replication crisis.
What counts as a QRP, however, is not clear. As I will discuss in the first part of this paper, there is no consensus on how to define the term, and ascriptions of the qualifier “questionable” often vary across disciplines, time, and even within single laboratories. This lack of clarity matters as it creates the risk of introducing methodological constraints that might create more harm than good. Practices labelled as ‘QRPs’ can be both beneficial and problematic for research practice and targeting them without a sound understanding of their dynamic and context-dependent nature risks creating unnecessary casualties in the fight for a more reliable scientific practice.
To start developing a more situated and dynamic picture of QRPs I will then turn my attention to a specific example of a dynamic QRP in the experimental life sciences, namely, the so-called “Far Western Blot” (FWB). The FWB is an experimental system that can be used to study protein-protein interactions but which for most of its existence has not seen a wide uptake in the community because it was seen as a QRP. This was mainly due to its (alleged) propensity to generate high levels of false positives and negatives. Interestingly, however, it seems that over the last few years the FWB slowly moved into the space of acceptable research practices. Analysing this shift and the reasons underlying it, I will argue a) that suppressing this practice deprived the research community of a powerful experimental tool and b) that the original judgment of the FWB was based on a simplistic and non-empirical assessment of its error-generating potential. Ultimately, it seems like the key QRP at work in the FWB case was the way in which the label “questionable” was assigned in the first place. I will argue that findings from this case can be extended to other QRPs in the experimental life sciences and that they point to a larger issue with how researchers judge the error-potential of new research practices.
David Hand (Professor Emeritus and Senior Research Investigator, Department of Mathematics,
Faculty of Natural Sciences, Imperial College London.)
ABSTRACT: Science progresses through an iterative process of formulating theories and comparing
them with empirical real-world data. Different camps of scientists will favour different
theories, until accumulating evidence renders one or more untenable. Not unnaturally,
people become attached to theories. Perhaps they invented a theory, and kudos arises
from being the originator of a generally accepted theory. A theory might represent a
life's work, so that being found wanting might be interpreted as failure. Perhaps
researchers were trained in a particular school, and acknowledging its shortcomings is
difficult. Because of this, tensions can arise between proponents of different theories.
The discipline of statistics is susceptible to precisely the same tensions. Here, however,
the tensions are not between different theories of "what is", but between different
strategies for shedding light on the real world from limited empirical data. This can be in
the form of how one measures discrepancy between the theory's predictions and
observations. It can be in the form of different ways of looking at empirical results. It can
be, at a higher level, because of differences between what is regarded as important in a
particular context. Or it can be for other reasons.
Perhaps the most familiar example of this tension within statistics is between different
approaches to inference. However, there are many other examples of such tensions.
This paper illustrates with several examples. We argue that the tension generally arises
as a consequence of inadequate care being taken in question formulation. That is,
insufficient thought is given to deciding exactly what one wants to know - to determining
"What is the question?".
The ideas and disagreements are illustrated with several examples.
The neglected importance of complexity in statistics and Metasciencejemille6
Daniele Fanelli
London School of Economics Fellow in Quantitative Methodology, Department of
Methodology, London School of Economics and Political Science.
ABSTRACT: Statistics is at war, and Metascience is ailing. This is partially due, the talk will argue, to
a paradigmatic blind-spot: the assumption that one can draw general conclusions about
empirical findings without considering the role played by context, conditions,
assumptions, and the complexity of methods and theories. Whilst ideally these
particularities should be unimportant in science, in practice they cannot be neglected in
most research fields, let alone in research-on-research.
This neglected importance of complexity is supported by theoretical arguments and
empirical findings (or the lack thereof) in the recent meta-analytical and metascientific
literature. The talk will overview this background and suggest how the complexity of
theories and methodologies may be explicitly factored into particular methodologies of
statistics and Metaresearch. The talk will then give examples of how this approach may
usefully complement existing paradigms, by translating results, methods and theories
into quantities of information that are evaluated using an information-compression logic.
Mathematically Elegant Answers to Research Questions No One is Asking (meta-a...jemille6
Uri Simonsohn (Professor, Department of Operations, Innovation and Data Sciences at Esade)
ABSTRACT: The statistical tools listed in the title share that a mathematically elegant solution has
become the consensus advice of statisticians, methodologists and some
mathematically sophisticated researchers writing tutorials and textbooks, and yet,
they lead research workers to meaningless answers, that are often also statistically
invalid. Part of the problem is that advice givers take the mathematical abstractions
of the tools they advocate for literally, instead of taking the actual behavior of
researchers seriously.
On Severity, the Weight of Evidence, and the Relationship Between the Twojemille6
Margherita Harris
Visiting fellow in the Department of Philosophy, Logic and Scientific Method at the London
School of Economics and Political Science.
ABSTRACT: According to the severe tester, one is justified in declaring to have evidence in support of a
hypothesis just in case the hypothesis in question has passed a severe test, one that it would be very
unlikely to pass so well if the hypothesis were false. Deborah Mayo (2018) calls this the strong
severity principle. The Bayesian, however, can declare to have evidence for a hypothesis despite not
having done anything to test it severely. The core reason for this has to do with the
(infamous) likelihood principle, whose violation is not an option for anyone who subscribes to the
Bayesian paradigm. Although the Bayesian is largely unmoved by the incompatibility between
the strong severity principle and the likelihood principle, I will argue that the Bayesian’s never-ending
quest to account for yet an other notion, one that is often attributed to Keynes (1921) and that is
usually referred to as the weight of evidence, betrays the Bayesian’s confidence in the likelihood
principle after all. Indeed, I will argue that the weight of evidence and severity may be thought of as
two (very different) sides of the same coin: they are two unrelated notions, but what brings them
together is the fact that they both make trouble for the likelihood principle, a principle at the core of
Bayesian inference. I will relate this conclusion to current debates on how to best conceptualise
uncertainty by the IPCC in particular. I will argue that failure to fully grasp the limitations of an
epistemology that envisions the role of probability to be that of quantifying the degree of belief to
assign to a hypothesis given the available evidence can be (and has been) detrimental to an
adequate communication of uncertainty.
Revisiting the Two Cultures in Statistical Modeling and Inference as they rel...jemille6
Aris Spanos (Wilson Schmidt Professor of Economics, Virginia Tech)
ABSTRACT: The discussion places the two cultures, the model-driven statistical modeling and the
algorithm-driven modeling associated with Machine Learning (ML) and Statistical
Learning Theory (SLT) in a broader context of paradigm shifts in 20th-century statistics,
which includes Fisher’s model-based induction of the 1920s and variations/extensions
thereof, the Data Science (ML, STL, etc.) and the Graphical Causal modeling in the
1990s. The primary objective is to compare and contrast the effectiveness of different
approaches to statistics in learning from data about phenomena of interest and relate
that to the current discussions pertaining to the statistics wars and their potential
casualties.
Comparing Frequentists and Bayesian Control of Multiple Testingjemille6
James Berger
ABSTRACT: A problem that is common to many sciences is that of having to deal with a multiplicity of statistical inferences. For instance, in GWAS (Genome Wide Association Studies), an experiment might consider 20 diseases and 100,000 genes, and conduct statistical tests of the 20x100,000=2,000,000 null hypotheses that a specific disease is associated with a specific gene. The issue is that selective reporting of only the ‘highly significant’ results could lead to many claimed disease/gene associations that turn out to be false, simply because of statistical randomness. In 2007, the seriousness of this problem was recognized in GWAS and extremely stringent standards were employed to resolve it. Indeed, it was recommended that tests for association should be conducted at an error probability of 5 x 10—7. Particle physicists similarly learned that a discovery would be reliably replicated only if the p-value of the relevant test was less than 5.7 x 10—7. This was because they had to account for a huge number of multiplicities in their analyses. Other sciences have continuing issues with multiplicity. In the Social Sciences, p-hacking and data dredging are common, which involve multiple analyses of data. Stopping rules in social sciences are often ignored, even though it has been known since 1933 that, if one keeps collecting data and computing the p-value, one is guaranteed to obtain a p-value less than 0.05 (or, indeed, any specified value), even if the null hypothesis is true. In medical studies that occur with strong oversight (e.g., by the FDA), control for multiplicity is mandated. There is also typically a large amount of replication, resulting in meta-analysis. But there are many situations where multiplicity is not handled well, such as subgroup analysis: one first tests for an overall treatment effect in the population; failing to find that, one tests for an effect among men or among women; failing to find that, one tests for an effect among old men or young men, or among old women or young women; …. I will argue that there is a single method that can address any such problems of multiplicity: Bayesian analysis, with the multiplicity being addressed through choice of prior probabilities of hypotheses. ... There are, of course, also frequentist error approaches (such as Bonferroni and FDR) for handling multiplicity of statistical inferences; indeed, these are much more familiar than the Bayesian approach. These are, however, targeted solutions for specific classes of problems and are not easily generalizable to new problems.
Clark Glamour
ABSTRACT: "Data dredging"--searching non experimental data for causal and other relationships and taking that same data to be evidence for those relationships--was historically common in the natural sciences--the works of Kepler, Cannizzaro and Mendeleev are examples. Nowadays, "data dredging"--using data to bring hypotheses into consideration and regarding that same data as evidence bearing on their truth or falsity--is widely denounced by both philosophical and statistical methodologists. Notwithstanding, "data dredging" is routinely practiced in the human sciences using "traditional" methods--various forms of regression for example. The main thesis of my talk is that, in the spirit and letter of Mayo's and Spanos’ notion of severe testing, modern computational algorithms that search data for causal relations severely test their resulting models in the process of "constructing" them. My claim is that in many investigations, principled computerized search is invaluable for reliable, generalizable, informative, scientific inquiry. The possible failures of traditional search methods for causal relations, multiple regression for example, are easily demonstrated by simulation in cases where even the earliest consistent graphical model search algorithms succeed. ... These and other examples raise a number of issues about using multiple hypothesis tests in strategies for severe testing, notably, the interpretation of standard errors and confidence levels as error probabilities when the structures assumed in parameter estimation are uncertain. Commonly used regression methods, I will argue, are bad data dredging methods that do not severely, or appropriately, test their results. I argue that various traditional and proposed methodological norms, including pre-specification of experimental outcomes and error probabilities for regression estimates of causal effects, are unnecessary or illusory in application. Statistics wants a number, or at least an interval, to express a normative virtue, the value of data as evidence for a hypothesis, how well the data pushes us toward the true or away from the false. Good when you can get it, but there are many circumstances where you have evidence but there is no number or interval to express it other than phony numbers with no logical connection with truth guidance. Kepler, Darwin, Cannizarro, Mendeleev had no such numbers, but they severely tested their claims by combining data dredging with severe testing.
The Duality of Parameters and the Duality of Probabilityjemille6
Suzanne Thornton
ABSTRACT: Under any inferential paradigm, statistical inference is connected to the logic of probability. Well-known debates among these various paradigms emerge from conflicting views on the notion of probability. One dominant view understands the logic of probability as a representation of variability (frequentism), and another prominent view understands probability as a measurement of belief (Bayesianism). The first camp generally describes model parameters as fixed values, whereas the second camp views parameters as random. Just as calibration (Reid and Cox 2015, “On Some Principles of Statistical Inference,” International Statistical Review 83(2), 293-308)--the behavior of a procedure under hypothetical repetition--bypasses the need for different versions of probability, I propose that an inferential approach based on confidence distributions (CD), which I will explain, bypasses the analogous conflicting perspectives on parameters. Frequentist inference is connected to the logic of probability through the notion of empirical randomness. Sample estimates are useful only insofar as one has a sense of the extent to which the estimator may vary from one random sample to another. The bounds of a confidence interval are thus particular observations of a random variable, where the randomness is inherited by the random sampling of the data. For example, 95% confidence intervals for parameter θ can be calculated for any random sample from a Normal N(θ, 1) distribution. With repeated sampling, approximately 95% of these intervals are guaranteed to yield an interval covering the fixed value of θ. Bayesian inference produces a probability distribution for the different values of a particular parameter. However, the quality of this distribution is difficult to assess without invoking an appeal to the notion of repeated performance. ... In contrast to a posterior distribution, a CD is not a probabilistic statement about the parameter, rather it is a data-dependent estimate for a fixed parameter for which a particular behavioral property holds. The Normal distribution itself, centered around the observed average of the data (e.g. average recovery times), can be a CD for θ. It can give any level of confidence. Such estimators can be derived through Bayesian or frequentist inductive procedures, and any CD, regardless of how it is obtained, guarantees performance of the estimator under replication for a fixed target, while simultaneously producing a random estimate for the possible values of θ.
On the interpretation of the mathematical characteristics of statistical test...jemille6
Statistical hypothesis tests are often misused and misinterpreted. Here I focus on one
source of such misinterpretation, namely an inappropriate notion regarding what the
mathematical theory of tests implies, and does not imply, when it comes to the
application of tests in practice. The view taken here is that it is helpful and instructive to be consciously aware of the essential difference between mathematical model and
reality, and to appreciate the mathematical model and its implications as a tool for
thinking rather than something that has a truth value regarding reality. Insights are presented regarding the role of model assumptions, unbiasedness and the alternative hypothesis, Neyman-Pearson optimality, multiple and data dependent testing.
The role of background assumptions in severity appraisal (jemille6
In the past decade discussions around the reproducibility of scientific findings have led to a re-appreciation of the importance of guaranteeing claims are severely tested. The inflation of Type 1 error rates due to flexibility in the data analysis is widely considered
one of the underlying causes of low replicability rates. Solutions, such as study preregistration, are becoming increasingly popular to combat this problem. Preregistration only allows researchers to evaluate the severity of a test, but not all
preregistered studies provide a severe test of a claim. The appraisal of the severity of a
test depends on background information, such as assumptions about the data generating process, and auxiliary hypotheses that influence the final choice for the
design of the test. In this article, I will discuss the difference between subjective and
inter-subjectively testable assumptions underlying scientific claims, and the importance
of separating the two. I will stress the role of justifications in statistical inferences, the
conditional nature of scientific conclusions following these justifications, and highlight
how severe tests could lead to inter-subjective agreement, based on a philosophical approach grounded in methodological falsificationism. Appreciating the role of background assumptions in the appraisal of severity should shed light on current discussions about the role of preregistration, interpreting the results of replication studies, and proposals to reform statistical inferences.
The two statistical cornerstones of replicability: addressing selective infer...jemille6
Tukey’s last published work in 2020 was an obscure entry on multiple comparisons in the
Encyclopedia of Behavioral Sciences, addressing the two topics in the title. Replicability
was not mentioned at all, nor was any other connection made between the two topics. I shall demonstrate how these two topics critically affect replicability using recently completed studies. I shall review how these have been addressed in the past. I shall
review in more detail the available ways to address selective inference. My conclusion is that conducting many small replicability studies without strict standardization is the way to assure replicability of results in science, and we should introduce policies to make this happen.
The replication crisis: are P-values the problem and are Bayes factors the so...jemille6
Today’s posterior is tomorrow’s prior. Dennis Lindley
It has been claimed that science is undergoing a replication crisis and that when looking for culprits, the cult of significance is the chief suspect. It has also been claimed that Bayes factors might provide a solution.
In my opinion, these claims are misleading and part of the problem is our understanding
of the purpose and nature of replication, which has only recently been subject to formal
analysis.
What we are or should be interested in is truth. Replication is a coherence not a correspondence requirement and one that has a strong dependence on the size
of the replication study
.
Consideration of Bayes factors raises a puzzling question. Should the Bayes factor for a replication study be calculated as if it were the initial study? If the answer is yes, the approach is not fully Bayesian and furthermore the Bayes factors will be subject to
exactly the same replication ‘paradox’ as P-values. If the answer is no, then in what
sense can an initially found Bayes factor be replicated and what are the implications for how we should view replication of P-values?
A further issue is that little attention has been paid to false negatives and, by extension
to true negative values. Yet, as is well known from the theory of diagnostic tests, it is
meaningless to consider the performance of a test in terms of false positives alone.
I shall argue that we are in danger of confusing evidence with the conclusions we draw and that any reforms of scientific practice should concentrate on producing evidence
that is reliable as it can be qua evidence. There are many basic scientific practices in
need of reform. Pseudoreplication, for example, and the routine destruction of
information through dichotomisation are far more serious problems than many matters of inferential framing that seem to have excited statisticians.
The ASA president Task Force Statement on Statistical Significance and Replic...jemille6
Yoav Benjamini's slides "The ASA president Task Force Statement on Statistical Significance and Replicability” for Special Session of the (remote) Phil Stat Forum: “Statistical Significance Test Anxiety” on 11 January 2022
D. Mayo's slides "“The Statistics Wars and Intellectual Conflicts of Interest” for Special Session of the (remote) Phil Stat Forum: “Statistical Significance Test Anxiety” on 11 January 2022
T. Pradeu & M. Lemoine: Philosophy in Science: Definition and Boundariesjemille6
Do philosophers of science frequently contribute to science, and if so how? Bibliometrics helps assess how surprisingly big is the corpus of papers authored or co-authored by philosophers and published in science. Indeed, several hundreds of philosophers have published in scientific journals. It is also possible to assess how influential this work has been in terms of citations, as compared to the average number of citations in the same journals in the same year. Unsurprisingly, many of these papers authored or co-authored by philosophers and published in scientific journals are poorly cited while a handful of them are widely cited. However, the most interesting result is that there is a significant corpus of papers authored by philosophers (both published in science journals and in philosophy journals) and significantly cited in science. It is more difficult, albeit crucial, to identify the most contributive philosophical papers, namely, those which have penetrated science not only through publication or citation in science journals, but also through discussion or endorsement by some scientists.
Based on the identification of this often neglected corpus, which we propose to call "philosophy in science" (PinS), it becomes possible to describe the most central features of this particular way of doing philosophy of science. The first feature is bibliographic: philosophers in science tend to cite little philosophy and a lot of (up-to-date) science. Second, they also address a scientific question rather than a philosophical question. Third, in doing so, they use traditional tools of philosophy of science, typically and mostly, conceptual analysis, explication of implicit claims, examination of the consistency of claims, assessment of the relevance of methods or models. More rarely, but very interestingly, they also make positive and original contributions by bridging domains of science or suggesting hypotheses.
This different context – in particular, the specific requirements for a publication in a peer-reviewed science journal – transforms philosophy of science. Is it still philosophy? What is the difference with approaches such as "philosophy of science in practice", "complementary science", "scientific philosophy", "theory of science", and naturalism? PinS faces a double "impostor syndrome": not entirely philosophical for philosophers, and not entirely scientific for scientists. In conclusion, we will explore how PinS can respond to this double challenge.
Acetabularia Information For Class 9 .docxvaibhavrinwa19
Acetabularia acetabulum is a single-celled green alga that in its vegetative state is morphologically differentiated into a basal rhizoid and an axially elongated stalk, which bears whorls of branching hairs. The single diploid nucleus resides in the rhizoid.
Safalta Digital marketing institute in Noida, provide complete applications that encompass a huge range of virtual advertising and marketing additives, which includes search engine optimization, virtual communication advertising, pay-per-click on marketing, content material advertising, internet analytics, and greater. These university courses are designed for students who possess a comprehensive understanding of virtual marketing strategies and attributes.Safalta Digital Marketing Institute in Noida is a first choice for young individuals or students who are looking to start their careers in the field of digital advertising. The institute gives specialized courses designed and certification.
for beginners, providing thorough training in areas such as SEO, digital communication marketing, and PPC training in Noida. After finishing the program, students receive the certifications recognised by top different universitie, setting a strong foundation for a successful career in digital marketing.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Francesca Gottschalk - How can education support child empowerment.pptxEduSkills OECD
Francesca Gottschalk from the OECD’s Centre for Educational Research and Innovation presents at the Ask an Expert Webinar: How can education support child empowerment?
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...
D. G. Mayo: The Replication Crises and its Constructive Role in the Philosophy of Statistics
1. The Replication Crises and its
Constructive Role in the
Philosophy of Statistics
Deborah G Mayo
November 3, 2018
2. What’s the constructive role of the
replication crisis?
• High profile failures of replication have resulted in
much soul-searching among statisticians
• Why do I say it has (or should have) a very
constructive role in philosophy of statistics?
2
3. What’s failed replication?
• Results found statistically significant are
not found significant by an independent
group, using new subjects, stricter
protocols and preregistration
3
4. Paradox of Replication
• Crisis of Replication: it’s too difficult to
replicate the small P-values others found
when we use preregistered protocols
• Leading to the complaint: It’s too easy to
get low P-values
4
5. That it’s too easy when you abuse or cheat teaches
a lot about:
I. Non-fallacious uses of statistical tests
II. Rationale for the role of probability in tests
III. How to reformulate tests
5
6. Most findings are false?
“Several methodologists have pointed out that the high
rate of nonreplication of research discoveries is a
consequence of the convenient, yet ill-founded strategy
of claiming conclusive research findings solely on the
basis of a single study assessed by formal statistical
significance, typically for a p-value less than 0.05.” …
It can be proven that most claimed research findings are
false.” (John Ioannidis 2005, 0696)
6
8. I. Non-fallacious tests
“[W]e need, not an isolated record, but a reliable
method of procedure. In relation to the test of
significance, we may say that a phenomenon is
experimentally demonstrable when we know how to
conduct an experiment which will rarely fail to give
us a statistically significant result.” (Fisher 1947, 14)
8
9. Fisher’s Simple Significance Test
“…to test the conformity of the particular data
under analysis with H0 in some respect:
…we find a function T = t(y) of the data, to be
called the test statistic, such that
• the larger the value of T the more inconsistent
are the data with H0;
• The random variable T = t(Y) has a
(numerically) known probability distribution
when H0 is true.
…the p-value corresponding to any t0bs as
p = p(t) = Pr(T ≥ t0bs; H0)”
(Mayo and Cox 2006, 81)
9
10. Testing Reasoning
• If even larger differences than t0bs occur fairly
frequently under H0 (i.e., P-value is not small),
there’s scarcely evidence of incompatibility
with H0
• Small P-value indicates some underlying
discrepancy from H0 because very probably you
would have seen a less impressive difference
than t0bs were H0 true.
• This still isn’t evidence of a genuine statistical
effect H1, let alone a scientific conclusion H*
Stat-Sub fallacy H => H*
10
11. Fallacy of rejection
• H* makes claims that haven’t been probed by the
statistical test
• The moves from experimental interventions to H*
don’t get enough attention–but your statistical
account should block it.
11
12. Neyman-Pearson (N-P) tests:
A null and alternative hypotheses H0, H1
that are exhaustive
H0: μ ≤ 0 vs. H1: μ > 0
• So this fallacy of rejection H1H* is impossible
• Rejecting H0 only indicates statistical alternatives
H1 (how discrepant from null)
12
13. Despite philosophical debates
between Fisher & N-P
• They both fall under tools for “appraising and
bounding the probabilities (under respective
hypotheses) of seriously misleading interpretations
of data” (Birnbaum 1970, 1033)–error probabilities
• I place all under the rubric of error statistics
• Confidence intervals, N-P and Fisherian tests,
resampling, randomization.
13
14. N-P and Fisher showed error
control is lost with selective
reporting
Sufficient finagling—cherry-picking, P-hacking,
significance seeking, multiple testing, look
elsewhere—may practically guarantee a preferred
claim H gets support, even if it’s unwarranted by
evidence
14
15. Minimal principle for evidence
If the test had little or no capability of finding
flaws with H (even if H is incorrect), then
agreement between data x0 and H provides
poor (or no) evidence for H
Such a test fails a minimal requirement for
evidence (severity principle)
• Holds outside of formal tests, to estimation,
prediction.
15
16. II. Key to revising roles of error
probabilities
• What bothers you with selective reporting,
cherry picking, stopping when the data look
good (biasing selection effects)?
• Not problems about long-runs—
16
17. We cannot say the case at hand has done a
good job of avoiding the sources of
misinterpreting data
18. 21 Word Solution: Report Sampling
Plan in Methods Section
• Replication researchers (re)discovered that data-
dependent hypotheses are a major source of
spurious significance levels.
“We report how we determined our sample size, all
data exclusions (if any), all manipulations, and all
measures in the study.”
(Simmons, Nelson, and Simonsohn 2012, 4)
18
19. Fishing for significance
(nominal vs. actual)
Suppose that twenty sets of differences have
been examined, that one difference seems large
enough to test and that this difference turns out
to be ‘significant at the 5 percent level.’ ….The
actual level of significance is not 5 percent,
but 64 percent! (Selvin 1970, 104)
(Morrison & Henkel’s Significance Test controversy
1970!)
19
20. Spurious P-Value
• He reports: Such results would be difficult to
achieve under the assumption of H0
• When in fact such results are common under
the assumption of H0
• Calls for adjusting the P-value to reflect the
actual error probability
20
21. Yet some accounts of evidence object
“Two problems that plague frequentist inference:
multiple comparisons and multiple looks, or…data
dredging and peeking at the data. The frequentist
solution to both problems involves adjusting the P-
value…
But adjusting the measure of evidence because
of considerations that have nothing to do with
the data defies scientific sense” (Goodman 1999,
1010)
(To his credit, he’s open about this; heads the Meta-Research
Innovation Center at Stanford) 21
22. Likelihood Principle (LP)
A pivotal disagreement in the philosophy of statistics
wars:
In classical Bayesian and likelihoodist accounts, the
import of the data is via the ratios of likelihoods of
hypotheses
Pr(x0;H0)/Pr(x0;H1)
Condition on fixed data x0, hypotheses vary
22
23. Hacking (1965)
• “Law of Likelihood”: x support hypothesis H0
less well than H1 if,
Pr(x;H0) < Pr(x;H1)
(abandoned in 1980)
• “there always is such a rival hypothesis viz., that
things just had to turn out the way they actually
did” (Barnard 1972, 129).
23
25. All error probabilities violate LP
(even without selection effects):
Sampling distributions, significance levels, power, all
depend on something more [than the likelihood
function]–something that is irrelevant in Bayesian
inference–namely the sample space
(Lindley 1971, 436)
The LP implies…the irrelevance of predesignation,
of whether a hypothesis was thought of beforehand
or was introduced to explain known effects
(Rosenkrantz 1977, 122)
25
26. How might intuitively unwarranted
inferences be blocked (without error
probabilities)?
Give a high prior probability to H0: no effect, in a
Bayesian analysis
26
27. Harold Jeffreys
“If mere improbability of the observations, given the
hypothesis, was the criterion, any hypothesis
whatever would be rejected. Everybody rejects the
conclusion” (Jeffreys 1939/1961, 385).
Add one of two things: error probabilities of the
method, or prior probabilities in the hypotheses
27
28. Problems with appealing to priors
to block inferences based on
selection effects
• It still wouldn’t show what researchers had
done wrong—battle of beliefs
• The believability of data-dredged hypotheses
is what makes them so seductive
• Additional source of flexibility, priors and
biasing selection effects
28
29. No help with our key problem
• How to distinguish the warrant for a single
hypothesis H with different methods
(e.g., one has biasing selection effects, another,
pre-registered results and precautions)?
• Since there’s a single H, its prior would be the
same
29
30. Criticisms of P-hackers lose force
• Wanting to promote an account that
downplays error probabilities, the researcher
deserving criticism is given a life-raft:
30
31. Bem’s “Feeling the Future” 2011:
ESP?
• Daryl Bem (2011): subjects do better than chance
at predicting the (erotic) picture shown in the
future
• Some locate the start of the Replication Crisis
With Bem
• Bem admits data dredging
• Bayesian critics resort to a default Bayesian prior
to (a point) null hypothesis
31
32. Bem’s Response
“Whenever the null hypothesis is sharply defined but
the prior distribution on the alternative hypothesis is
diffused over a wide range of values, as it is [here] it
boosts the probability that any observed data will be
higher under the null hypothesis than under the
alternative.
This is known as the Lindley-Jeffreys paradox: A
frequentist [can always] be contradicted by a
…Bayesian analysis that concludes that the same data
are more likely under the null.” (Bem et al. 2011, 717)
32
33. III Reformulate Tests: P-values don’t
give an effect size
Severity function: SEV(Test T, data x, claim C)
• Tests are reformulated in terms of a discrepancy γ
from H0
• Instead of a binary cut-off (significant or not) the
particular outcome is used to infer discrepancies
that are or are not warranted
33
34. 1-sided Normal test:
H0: μ ≤ 0 vs. H1: μ > 0 (Let σ = 1 n = 100)
Reject H0 whenever M ≥ 2SE: M ≥ 0.2
M is the sample mean (significance level = .025)
Let M = .2, so I reject H0.
1SE = s/√n = .1
What can you infer?
34
35. Some ask: Does this mean I can infer μ = .3?
• Inferences not in terms of points, but μ > 0 + γ
• Do we have evidence for μ > .3?
No.
• 84% of the time, M would have been larger than it is
even if μ = .3: SEV(μ > .3) is low (.16)
Pr (M < .2; .3 ) = .16
35
37. Improves on confidence intervals
which inherit problems of N-P
tests
• We do not fix a single confidence level,
• The evidential warrant for different points
in any interval are distinguished
• Go beyond a “performance goal”
37
38. Quick sum-up
• Main source of hand-wringing stems from
biasing selection effects
• These alter error probabilities of methods
• They don’t alter evidence in accounts that
obey the Likelihood Principle
• To a follower of the LP, the error
statistician is considering “imaginary data”
and “intentions”
38
39. • To the severe tester, the LP precludes key way to
block spurious results:
What’s the value of preregistered reports?
It’s that your appraisal is altered once you consider
the probability that some hypotheses, stopping
point, …or other could have led to a false positive
• Constructive role of replication crisis:
Biasing selection effects impinge on error
probabilities
Error probabilities impinge on well-testedness
39
40. • Can block inferences without appeal to error
probabilities: background beliefs (probabilism)
• Gives a life-raft to the P-hacker and cherry
picker; puts blame in the wrong place
• Significance tests are a small part of error
statistics, need reformulation and a new
rationale
• Error probabilities used to assess how well-
probed claims are (probativism)
40
42. References
• Barnard, G. (1972). ‘The Logic of Statistical Inference (Review of “The Logic of
Statistical Inference” by Ian Hacking)’, British Journal for the Philosophy of Science
23(2), 123–32.
• Bem, J. 2011. “Feeling the Future: Experimental Evidence for Anomalous
Retroactive Influences on Cognition and Affect”, Journal of Personality and Social
Psychology 100(3), 407-425.
• Bem, J., Utts, J., and Johnson, W. 2011. “Must Psychologists Change the Way
They Analyze Their Data?”, Journal of Personality and Social Psychology 101(4),
716-719.
• Birnbaum, A. 1970. “Statistical Methods in Scientific Inference (letter to the
Editor).” Nature 225 (5237) (March 14): 1033.
• Fisher, R. A. 1947. The Design of Experiments 4th ed., Edinburgh: Oliver and Boyd.
• Goodman SN. 1999. “Toward evidence-based medical statistics. 2: The Bayes
factor,” Annals of Internal Medicine 1999; 130:1005 –1013.
• Hacking, I. (1965). Logic of Statistical Inference. Cambridge: Cambridge University
Press.
• Hacking, I. (1980). ‘The Theory of Probable Inference: Neyman, Peirce and
Braithwaite’, in Mellor, D. (ed.), Science, Belief and Behavior: Essays in Honour of
R. B. Braithwaite, Cambridge: Cambridge University Press, pp. 141–60.
• Ioannidis, J. (2005). “Why Most Published Research Findings are False”, PLoS
Medicine 2(8), 0696–0701.
• Jeffreys, H. ([1939]/ 1961). Theory of Probability. Oxford: Oxford University
Press.
42
43. • Lindley, D. V. 1971. “The Estimation of Many Parameters.” In Foundations of
Statistical Inference, edited by V. P. Godambe and D. A. Sprott, 435–455. Toronto:
Holt, Rinehart and Winston.
• Mayo, D. G. 1996. Error and the Growth of Experimental Knowledge. Science and
Its Conceptual Foundation. Chicago: University of Chicago Press.
• Mayo, D. G. 2018. Statistical Inference as Severe Testing: How to Get Beyond the
Statistics Wars, Cambridge: Cambridge University Press.
• Mayo, D. G. and Cox, D. R. (2006). "Frequentist Statistics as a Theory of Inductive
Inference” in Rojo, J. (ed.) The Second Erich L. Lehmann Symposium: Optimality,
2006, Lecture Notes-Monograph Series, Volume 49, Institute of Mathematical
Statistics: 247-275.
• Mayo, D. G., and A. Spanos. 2006. “Severe Testing as a Basic Concept in a
Neyman–Pearson Philosophy of Induction.” British Journal for the Philosophy of
Science 57 (2) (June 1): 323–357.
• Mayo, D. G., and A. Spanos. 2011. “Error Statistics.” In Philosophy of
Statistics, edited by Prasanta S. Bandyopadhyay and Malcolm R. Forster,
7:152–198. Handbook of the Philosophy of Science. The Netherlands:
Elsevier.
• Morrison, D. E., and R. E. Henkel, ed. 1970. The Significance Test
Controversy: A Reader. Chicago: Aldine De Gruyter.
• Pearson, E. S. & Neyman, J. (1930). “On the problem of two samples”, Joint
Statistical Papers by J. Neyman & E.S. Pearson, 99-115 (Berkeley: U. of
Calif. Press). First published in Bul. Acad. Pol.Sci. 73-96.
43
44. • Rosenkrantz, R. 1977. Inference, Method and Decision: Towards a Bayesian
Philosophy of Science. Dordrecht, The Netherlands: D. Reidel.
• Savage, L. J. 1962. The Foundations of Statistical Inference: A Discussion.
London: Methuen.
• Selvin, H. 1970. “A critique of tests of significance in survey research. In The
significance test controversy, edited by D. Morrison and R. Henkel, 94-106.
Chicago: Aldine De Gruyter.
• Simmons, J. Nelson, L. and Simonsohn, U. (2012). “A 21 Word Solution”,
Dialogue: The Official Newsletter of the Society for Personality and Social
Psychology, 26(2), 4–7.
• Wagenmakers, E-J., 2007. “A Practical Solution to the Pervasive Problems of P
values”, Psychonomic Bulletin & Review 14(5): 779-804.
44
45. SEV(μ > μ1) = Pr( M < .2; μ = .3 )
= Pr( Z < -1) = .16
Z = (.2 - .3)/.1 = -1
45
46. Severity for Test T+:
SEV(T+, d(x0), claim C)
Normal testing: H0: μ ≤ μ0 vs. H1: μ > μ0 known σ;
discrepancy parameter γ; μ1 = μ0 +γ; d0 = d(x0)
(observed value of test statistic) √n(M - μ0)/σ
SIR: (Severity Interpretation with low P-values)
• (a): (high): If there’s a very low probability that so
large a d0 would have resulted, if μ were no greater
than μ1, then d0 it indicates μ > μ1: SEV(μ > μ1) is
high.
• (b): (low) If there is a fairly high probability that d0
would have been larger than it is, even if μ = μ1, then
d0 is not a good indication μ > μ1: SEV(μ > μ1) is low.46
47. SIN: (Severity Interpretation for
Negative results)
• (a): (high) If there is a very high probability
that d0 would have been larger than it is, were
μ > μ1, then μ ≤ μ1 passes the test with high
severity: SEV(μ ≤ μ1) is high.
• (b): (low) If there is a low probability that d0
would have been larger than it is, even if μ >
μ1, then μ ≤ μ1 passes with low severity:
SEV(μ ≤ μ1) is low.
47
48. Jimmy Savage on the LP:
“According to Bayes' theorem,…. if y is the
datum of some other experiment, and if it
happens that P(x|µ) and P(y|µ) are
proportional functions of µ (that is,
constant multiples of each other), then
each of the two data x and y have exactly
the same thing to say about the values of
µ…” (Savage 1962, p. 17)
48