This document discusses measurement uncertainty. It defines measurement uncertainty as a parameter included with any measurement result that accounts for possible errors. It describes sources of uncertainty like sampling, storage conditions, and personal effects. The document outlines methods of calculating uncertainty using the standard deviation, and explains why assessing uncertainty is important for interpreting results and ensuring measurement quality. Measurement uncertainty is a key component of any measurement result.
This document discusses various concepts related to errors and accuracy in chemical analysis. It defines different types of errors like gross errors, systematic errors, and random errors. It explains how to classify errors based on their origin and how to minimize different types of errors. The document also covers key statistical concepts like mean, median, standard deviation, normal distribution, precision and accuracy that are important for understanding errors in chemical analysis.
The significant figures in a numerical expression are defined as all those whose values are known with certainty with one additional digit whose value is uncertain.
Errors - pharmaceutical analysis -1, bpharm 1st semester, notes, topic errors
full details and answer about error
TN DR MGR UNIVERSITY
by Kumaran.M.pharm, professor
The document discusses various types of errors that can occur in quantitative chemical analysis, including random errors, systematic errors, determinate errors, indeterminate errors, and errors due to faulty instrumentation, impure reagents, or improper methodology. It also describes ways to minimize errors, such as calibrating apparatus, running blanks and controls, using multiple analytical techniques, and performing replicate measurements. Accuracy is defined as how close a measurement is to the true value, while precision refers to the reproducibility of measurements.
Here are the steps to calculate sensitivity, specificity, positive predictive value, negative predictive value, and efficiency for the given diagnostic test:
* True Positives (TP) = Number of HIV+ samples correctly identified as positive by the test = 120 - 15 = 105
* True Negatives (TN) = Number of HIV- samples correctly identified as negative by the test = 300 - (120 + 4) = 176
* False Positives (FP) = Number of HIV- samples incorrectly identified as positive by the test = 4
* False Negatives (FN) = Number of HIV+ samples incorrectly identified as negative by the test = 15
Sensitivity = TP / (TP + FN) = 105 / (105
This document discusses measurement uncertainty. It defines measurement uncertainty as a parameter included with any measurement result that accounts for possible errors. It describes sources of uncertainty like sampling, storage conditions, and personal effects. The document outlines methods of calculating uncertainty using the standard deviation, and explains why assessing uncertainty is important for interpreting results and ensuring measurement quality. Measurement uncertainty is a key component of any measurement result.
This document discusses various concepts related to errors and accuracy in chemical analysis. It defines different types of errors like gross errors, systematic errors, and random errors. It explains how to classify errors based on their origin and how to minimize different types of errors. The document also covers key statistical concepts like mean, median, standard deviation, normal distribution, precision and accuracy that are important for understanding errors in chemical analysis.
The significant figures in a numerical expression are defined as all those whose values are known with certainty with one additional digit whose value is uncertain.
Errors - pharmaceutical analysis -1, bpharm 1st semester, notes, topic errors
full details and answer about error
TN DR MGR UNIVERSITY
by Kumaran.M.pharm, professor
The document discusses various types of errors that can occur in quantitative chemical analysis, including random errors, systematic errors, determinate errors, indeterminate errors, and errors due to faulty instrumentation, impure reagents, or improper methodology. It also describes ways to minimize errors, such as calibrating apparatus, running blanks and controls, using multiple analytical techniques, and performing replicate measurements. Accuracy is defined as how close a measurement is to the true value, while precision refers to the reproducibility of measurements.
Here are the steps to calculate sensitivity, specificity, positive predictive value, negative predictive value, and efficiency for the given diagnostic test:
* True Positives (TP) = Number of HIV+ samples correctly identified as positive by the test = 120 - 15 = 105
* True Negatives (TN) = Number of HIV- samples correctly identified as negative by the test = 300 - (120 + 4) = 176
* False Positives (FP) = Number of HIV- samples incorrectly identified as positive by the test = 4
* False Negatives (FN) = Number of HIV+ samples incorrectly identified as negative by the test = 15
Sensitivity = TP / (TP + FN) = 105 / (105
This document discusses errors in measurement and analysis. It defines absolute and relative errors as the difference between experimental and true values. Errors are classified as determinate (systemic) or indeterminate (random). Determinate errors include personal, instrumental, method, additive and proportional errors. Indeterminate errors cannot be avoided and come from unknown causes. Accuracy refers to how close a measurement is to the true value, while precision describes the reproducibility of measurements. Significant figures convey the precision or accuracy of numerical values. The document provides examples and rules for determining significant figures.
Different Approaches in Estimating Measurement UncertaintyPECB
Measurement uncertainty is the significant part of organizations’ decision making and risk assessment process because all type of organizations base their decisions on reports enclosing measurable data. A measurement result of a laboratory is an estimate of the value of the measure, and quality of this estimate depends on the inevitable uncertainty. Giving quantitative indication of the quality of the measurement result is obligatory so that those who use it can assess its reliability. Without such an indication, measurement results cannot be compared, either among themselves or with reference values given in a specification or standard.
Main points covered:
• Measurement uncertainty vs. measurement error
• Bottom- up approach for estimating uncertainty
• Top- down approach for estimating uncertainty
Presenter:
This webinar was presented by Bahar Hosseinzadeh, PECB Certified Trainer and Sales Manager, ISO/IEC 17025 Consultancy Project Manager at PQP Ltd.
Link of the recorded session published on YouTube: https://youtu.be/kR47GnhNjPw
This document discusses audit sampling, which involves selecting a subset of data from a population to make inferences about the whole population. It defines audit sampling and explains that it provides information on how many items to examine, which items to select, and how to evaluate sample results. The document outlines the general approaches of statistical and non-statistical sampling and explains key steps like planning, selecting, and evaluating a sample. It also discusses factors that affect sample size and how to project errors in a sample to the overall population.
Chapter 10
Data Interpretation Issues
Learning Objectives
• Distinguish between random and
systematic errors
• State and describe sources of bias
• Identify techniques to reduce bias at the
design and analysis phases of a study
• Define what is meant by the term
confounding and provide three examples
• Describe methods to control confounding
Validity of Study Designs
• The degree to which the inference drawn
from a study, is warranted when account it
taken of the study, methods, the
representativeness of the study sample,
and the nature of the population from
which it is drawn.
Validity of Study Designs
• Two components of validity:
– Internal validity
– External validity
Internal Validity
• A study is said to have internal validity
when there have been proper selection of
study groups and a lack of error in
measurement.
• Concerned with the appropriate
measurement of exposure, outcome, and
association between exposure and
disease.
External Validity
• External validity implies the ability to
generalize beyond a set of observations to
some universal statement.
• A study is externally valid, or
generalizable, if it allows unbiased
inferences regarding some other target
population beyond the subjects in the
study.
Sources of Error in
Epidemiologic Research
• Random errors
• Systematic errors (bias)
Random Errors
• Reflect fluctuations around a true value of
a parameter because of sampling
variability.
Factors That Contribute to
Random Error
• Poor precision
• Sampling error
• Variability in measurement
Poor Precision
• Occurs when the factor being measured is
not measured sharply.
• Analogous to aiming a rifle at a target that
is not in focus.
• Precision can be increased by increasing
sample size or the number of
measurements.
• Example: Bogalusa Heart Study
Sampling Error
• Arises when obtained sample values
(statistics) differ from the values
(parameters) of the parent population.
• Although there is no way to prevent a
non-representative sample from
occurring, increasing the sample size
can reduce the likelihood of its
happening.
Variability in Measurement
• The lack of agreement in results from
time to time reflects random error
inherent in the type of measurement
procedure employed.
Bias (Systematic Errors)
• “Deviation of results or inferences
from the truth, or processes leading to
such deviation. Any trend in the
collection, analysis, interpretation,
publication, or review of data that can
lead to conclusions that are
systematically different from the
truth.”
Factors That Contribute to
Systematic Errors
• Selection bias
• Information bias
• Confounding
Selection Bias
• Refers to distortions that result from procedures
used to select subjects and from factors that
influence participation in the study.
• Arises when the relation between exposure and
disease is different for th ...
Errors in research can be defined as the difference between observed or calculated values and the true values. There are two types of errors: sampling errors, which result from chance selection in sampling, and non-sampling errors from other sources. Non-sampling errors include errors from incorrectly specifying the target population, using non-random selection methods, having an incomplete sampling frame, non-response, surrogate data, measurement issues, experimental design flaws, errors in interviews, materials, observations, concepts, and communication. Researchers can reduce errors through careful research design and by estimating and measuring the errors that cannot be eliminated.
This document discusses various techniques for analyzing quantitative and qualitative data in research. It outlines different statistical procedures that can be used depending on the type of data, such as descriptive statistics for descriptive research data, correlations for examining relationships between variables, and t-tests or analysis of variance for experimental data involving comparisons between groups. Both parametric and non-parametric statistical methods are covered. The document also addresses qualitative data analysis and multivariate analysis techniques like multiple regression, discriminant analysis, and factor analysis.
A statistical error is the difference between a sample value and the true population value. There are two main types of error - sampling error and non-sampling error. Sampling error occurs when the sample is not fully representative of the population, while non-sampling error can arise from factors like non-response, measurement issues, interviewer errors, adjustments to the data, or processing mistakes. Common ways to measure and reduce sampling error include calculating the standard error, sample size, and sample design.
This document discusses different types of errors that can occur in analytical chemistry measurements and methods. It describes determinate errors, which include instrumental errors from faulty tools, methodic errors from defective experimental methods, operational errors from improper technique, and personal errors from the analyst. It also discusses indeterminate errors, which are random errors that cannot be attributed to a known cause. The document explains how errors can propagate in calculations and discusses accuracy and precision in measurements.
This document provides an overview of a course on measurements and instrumentation. The course will cover topics such as measurement systems, calibration, accuracy, precision, and instruments for measuring length, force, torque, strain, pressure, flow, and temperature. The objectives are to understand instrumentation principles and learn basic measurement methods. The primary textbook will be Theory and Design for Mechanical Measurements by Figliola and Beasley, along with class notes.
This document discusses laboratory errors, their causes, types, and impacts. It describes that errors can occur in the pre-analytical, analytical, and post-analytical phases of testing and provide examples of errors in each phase. Errors are categorized as either determinate (systemic) errors, which are reproducible and can be identified and corrected, or indeterminate (random) errors, which are caused by uncontrollable variables and cannot be eliminated. The key goals are improving precision by reducing indeterminate errors and improving accuracy by reducing determinate errors.
Research 101: Quantitative Data PreparationHarold Gamero
This document provides an overview of important steps in data preparation for research, including data coding, entry, checking for missing values and outliers, testing for normality, assessing dimensionality and reliability of scales. Specifically, it discusses coding survey responses numerically, entering data into statistical programs, identifying and addressing missing data, transforming variables as needed, identifying outlier data, testing data for normal distribution, confirming the dimensionality of multi-dimensional constructs using factor analysis, and calculating reliability coefficients of scales. The goal is to prepare data for statistical analysis and ensure it meets necessary assumptions of different statistical tests.
This document discusses potential sources of missing data in meta-analyses, including studies not being found, outcomes not being fully reported, missing standard deviations or other information needed for the meta-analysis, and missing participants. It also covers concepts related to missing data like whether it is missing completely at random, missing at random, or informatively missing. Strategies for dealing with missing data include simple or multiple imputation as well as sensitivity analyses. Specific examples discussed include imputing missing standard deviations or correlation coefficients.
Researchers must carefully screen data before conducting statistical analysis to address issues that could impact results. This involves evaluating accuracy, assessing effects of missing or outlier data, and determining if the data fits assumptions. Specifically, researchers should check for errors, missing patterns, extreme outliers, normality, linear relationships, and equal variability across values. Addressing these quality issues through data screening allows researchers to have confidence in their analysis and conclusions drawn from the data.
SAMPLE SIZE CALCULATION IN DIFFERENT STUDY DESIGNS AT.pptxssuserd509321
The document discusses factors that affect sample size calculation in different study designs. It provides examples of calculating sample sizes for descriptive cross-sectional studies, case-control studies, cohort studies, comparative studies, and randomized controlled trials. The key factors discussed are the level of confidence, power, expected proportions or means in groups, margin of error, and standard deviation. Sample size is affected by the type of study design, variables being qualitative or quantitative, and the goal of establishing equivalence, superiority or non-inferiority between groups. Electronic resources are provided for calculating sample sizes.
This document provides an introduction to statistics and research design. It discusses key concepts in descriptive and inferential statistics, including scales of measurement, measures of central tendency and variability, sampling methods, and parameters versus statistics. Descriptive statistics are used to summarize and describe data, while inferential statistics make predictions about a population based on a sample. Research design involves the plan for investigating research questions using statistical analysis tools and following the logic of hypothesis testing.
The document discusses non-parametric tests and provides information about when to use them. Non-parametric tests make fewer assumptions about the distribution of population values and can be used when sample sizes are small or the data is ordinal. Examples of non-parametric tests provided include the sign test, chi-square test, Mann-Whitney U test, and Kruskal-Wallis test. The general steps to perform a non-parametric test are also outlined.
Errors refer to the differences between measured and true values in measurements and experiments. It is impossible to perform analyses that are completely free of errors. Errors are caused by faulty instruments, imprecise measurements, and random variations. Methods to reduce errors include frequent calibration of instruments, analysis of known samples, and repeating measurements. Precision refers to the reproducibility of measurements and can be estimated through repeated measurements of replicate samples. Accuracy is the closeness of a measurement to the true value and is more difficult to determine than precision. There are two main types of errors: determinate errors caused by mistakes that can be avoided, and accidental errors that are difficult to control. Methods to minimize errors include calibration, using blanks, comparative analysis techniques, and repeated
Introduction to Pharmaceutical ChemistryPriti Kokate
Chapter No. 1 from pharmaceutical chemistry , updated syllabus notes as per MSBTE
1.Introduction to pharmaceutical chemistry
Topic covers following bits
#Scope
#Objective
#Sources & Types Of Errors
#Impurities in Pharmaceuticals
#Limit Test For
*Chloride
*Sulphate
*Iron
*Heavy Metal
*Arsenic
PPT on Sample Size, Importance of Sample Size,Naveen K L
This document discusses factors related to determining sample size for research studies. It defines key terms like sample size, population and importance of sample size. The selection of sample size involves planning the study, specifying parameters, choosing an effect size, and computing the sample size based on those factors. Sample size is influenced by expected effect size, study power, heterogeneity, error risk, and other variables. Dropouts from the sample during a study also impact sample size calculations. Proper determination of sample size is important for obtaining meaningful results and conducting ethical research.
This document discusses errors in measurement and analysis. It defines absolute and relative errors as the difference between experimental and true values. Errors are classified as determinate (systemic) or indeterminate (random). Determinate errors include personal, instrumental, method, additive and proportional errors. Indeterminate errors cannot be avoided and come from unknown causes. Accuracy refers to how close a measurement is to the true value, while precision describes the reproducibility of measurements. Significant figures convey the precision or accuracy of numerical values. The document provides examples and rules for determining significant figures.
Different Approaches in Estimating Measurement UncertaintyPECB
Measurement uncertainty is the significant part of organizations’ decision making and risk assessment process because all type of organizations base their decisions on reports enclosing measurable data. A measurement result of a laboratory is an estimate of the value of the measure, and quality of this estimate depends on the inevitable uncertainty. Giving quantitative indication of the quality of the measurement result is obligatory so that those who use it can assess its reliability. Without such an indication, measurement results cannot be compared, either among themselves or with reference values given in a specification or standard.
Main points covered:
• Measurement uncertainty vs. measurement error
• Bottom- up approach for estimating uncertainty
• Top- down approach for estimating uncertainty
Presenter:
This webinar was presented by Bahar Hosseinzadeh, PECB Certified Trainer and Sales Manager, ISO/IEC 17025 Consultancy Project Manager at PQP Ltd.
Link of the recorded session published on YouTube: https://youtu.be/kR47GnhNjPw
This document discusses audit sampling, which involves selecting a subset of data from a population to make inferences about the whole population. It defines audit sampling and explains that it provides information on how many items to examine, which items to select, and how to evaluate sample results. The document outlines the general approaches of statistical and non-statistical sampling and explains key steps like planning, selecting, and evaluating a sample. It also discusses factors that affect sample size and how to project errors in a sample to the overall population.
Chapter 10
Data Interpretation Issues
Learning Objectives
• Distinguish between random and
systematic errors
• State and describe sources of bias
• Identify techniques to reduce bias at the
design and analysis phases of a study
• Define what is meant by the term
confounding and provide three examples
• Describe methods to control confounding
Validity of Study Designs
• The degree to which the inference drawn
from a study, is warranted when account it
taken of the study, methods, the
representativeness of the study sample,
and the nature of the population from
which it is drawn.
Validity of Study Designs
• Two components of validity:
– Internal validity
– External validity
Internal Validity
• A study is said to have internal validity
when there have been proper selection of
study groups and a lack of error in
measurement.
• Concerned with the appropriate
measurement of exposure, outcome, and
association between exposure and
disease.
External Validity
• External validity implies the ability to
generalize beyond a set of observations to
some universal statement.
• A study is externally valid, or
generalizable, if it allows unbiased
inferences regarding some other target
population beyond the subjects in the
study.
Sources of Error in
Epidemiologic Research
• Random errors
• Systematic errors (bias)
Random Errors
• Reflect fluctuations around a true value of
a parameter because of sampling
variability.
Factors That Contribute to
Random Error
• Poor precision
• Sampling error
• Variability in measurement
Poor Precision
• Occurs when the factor being measured is
not measured sharply.
• Analogous to aiming a rifle at a target that
is not in focus.
• Precision can be increased by increasing
sample size or the number of
measurements.
• Example: Bogalusa Heart Study
Sampling Error
• Arises when obtained sample values
(statistics) differ from the values
(parameters) of the parent population.
• Although there is no way to prevent a
non-representative sample from
occurring, increasing the sample size
can reduce the likelihood of its
happening.
Variability in Measurement
• The lack of agreement in results from
time to time reflects random error
inherent in the type of measurement
procedure employed.
Bias (Systematic Errors)
• “Deviation of results or inferences
from the truth, or processes leading to
such deviation. Any trend in the
collection, analysis, interpretation,
publication, or review of data that can
lead to conclusions that are
systematically different from the
truth.”
Factors That Contribute to
Systematic Errors
• Selection bias
• Information bias
• Confounding
Selection Bias
• Refers to distortions that result from procedures
used to select subjects and from factors that
influence participation in the study.
• Arises when the relation between exposure and
disease is different for th ...
Errors in research can be defined as the difference between observed or calculated values and the true values. There are two types of errors: sampling errors, which result from chance selection in sampling, and non-sampling errors from other sources. Non-sampling errors include errors from incorrectly specifying the target population, using non-random selection methods, having an incomplete sampling frame, non-response, surrogate data, measurement issues, experimental design flaws, errors in interviews, materials, observations, concepts, and communication. Researchers can reduce errors through careful research design and by estimating and measuring the errors that cannot be eliminated.
This document discusses various techniques for analyzing quantitative and qualitative data in research. It outlines different statistical procedures that can be used depending on the type of data, such as descriptive statistics for descriptive research data, correlations for examining relationships between variables, and t-tests or analysis of variance for experimental data involving comparisons between groups. Both parametric and non-parametric statistical methods are covered. The document also addresses qualitative data analysis and multivariate analysis techniques like multiple regression, discriminant analysis, and factor analysis.
A statistical error is the difference between a sample value and the true population value. There are two main types of error - sampling error and non-sampling error. Sampling error occurs when the sample is not fully representative of the population, while non-sampling error can arise from factors like non-response, measurement issues, interviewer errors, adjustments to the data, or processing mistakes. Common ways to measure and reduce sampling error include calculating the standard error, sample size, and sample design.
This document discusses different types of errors that can occur in analytical chemistry measurements and methods. It describes determinate errors, which include instrumental errors from faulty tools, methodic errors from defective experimental methods, operational errors from improper technique, and personal errors from the analyst. It also discusses indeterminate errors, which are random errors that cannot be attributed to a known cause. The document explains how errors can propagate in calculations and discusses accuracy and precision in measurements.
This document provides an overview of a course on measurements and instrumentation. The course will cover topics such as measurement systems, calibration, accuracy, precision, and instruments for measuring length, force, torque, strain, pressure, flow, and temperature. The objectives are to understand instrumentation principles and learn basic measurement methods. The primary textbook will be Theory and Design for Mechanical Measurements by Figliola and Beasley, along with class notes.
This document discusses laboratory errors, their causes, types, and impacts. It describes that errors can occur in the pre-analytical, analytical, and post-analytical phases of testing and provide examples of errors in each phase. Errors are categorized as either determinate (systemic) errors, which are reproducible and can be identified and corrected, or indeterminate (random) errors, which are caused by uncontrollable variables and cannot be eliminated. The key goals are improving precision by reducing indeterminate errors and improving accuracy by reducing determinate errors.
Research 101: Quantitative Data PreparationHarold Gamero
This document provides an overview of important steps in data preparation for research, including data coding, entry, checking for missing values and outliers, testing for normality, assessing dimensionality and reliability of scales. Specifically, it discusses coding survey responses numerically, entering data into statistical programs, identifying and addressing missing data, transforming variables as needed, identifying outlier data, testing data for normal distribution, confirming the dimensionality of multi-dimensional constructs using factor analysis, and calculating reliability coefficients of scales. The goal is to prepare data for statistical analysis and ensure it meets necessary assumptions of different statistical tests.
This document discusses potential sources of missing data in meta-analyses, including studies not being found, outcomes not being fully reported, missing standard deviations or other information needed for the meta-analysis, and missing participants. It also covers concepts related to missing data like whether it is missing completely at random, missing at random, or informatively missing. Strategies for dealing with missing data include simple or multiple imputation as well as sensitivity analyses. Specific examples discussed include imputing missing standard deviations or correlation coefficients.
Researchers must carefully screen data before conducting statistical analysis to address issues that could impact results. This involves evaluating accuracy, assessing effects of missing or outlier data, and determining if the data fits assumptions. Specifically, researchers should check for errors, missing patterns, extreme outliers, normality, linear relationships, and equal variability across values. Addressing these quality issues through data screening allows researchers to have confidence in their analysis and conclusions drawn from the data.
SAMPLE SIZE CALCULATION IN DIFFERENT STUDY DESIGNS AT.pptxssuserd509321
The document discusses factors that affect sample size calculation in different study designs. It provides examples of calculating sample sizes for descriptive cross-sectional studies, case-control studies, cohort studies, comparative studies, and randomized controlled trials. The key factors discussed are the level of confidence, power, expected proportions or means in groups, margin of error, and standard deviation. Sample size is affected by the type of study design, variables being qualitative or quantitative, and the goal of establishing equivalence, superiority or non-inferiority between groups. Electronic resources are provided for calculating sample sizes.
This document provides an introduction to statistics and research design. It discusses key concepts in descriptive and inferential statistics, including scales of measurement, measures of central tendency and variability, sampling methods, and parameters versus statistics. Descriptive statistics are used to summarize and describe data, while inferential statistics make predictions about a population based on a sample. Research design involves the plan for investigating research questions using statistical analysis tools and following the logic of hypothesis testing.
The document discusses non-parametric tests and provides information about when to use them. Non-parametric tests make fewer assumptions about the distribution of population values and can be used when sample sizes are small or the data is ordinal. Examples of non-parametric tests provided include the sign test, chi-square test, Mann-Whitney U test, and Kruskal-Wallis test. The general steps to perform a non-parametric test are also outlined.
Errors refer to the differences between measured and true values in measurements and experiments. It is impossible to perform analyses that are completely free of errors. Errors are caused by faulty instruments, imprecise measurements, and random variations. Methods to reduce errors include frequent calibration of instruments, analysis of known samples, and repeating measurements. Precision refers to the reproducibility of measurements and can be estimated through repeated measurements of replicate samples. Accuracy is the closeness of a measurement to the true value and is more difficult to determine than precision. There are two main types of errors: determinate errors caused by mistakes that can be avoided, and accidental errors that are difficult to control. Methods to minimize errors include calibration, using blanks, comparative analysis techniques, and repeated
Introduction to Pharmaceutical ChemistryPriti Kokate
Chapter No. 1 from pharmaceutical chemistry , updated syllabus notes as per MSBTE
1.Introduction to pharmaceutical chemistry
Topic covers following bits
#Scope
#Objective
#Sources & Types Of Errors
#Impurities in Pharmaceuticals
#Limit Test For
*Chloride
*Sulphate
*Iron
*Heavy Metal
*Arsenic
PPT on Sample Size, Importance of Sample Size,Naveen K L
This document discusses factors related to determining sample size for research studies. It defines key terms like sample size, population and importance of sample size. The selection of sample size involves planning the study, specifying parameters, choosing an effect size, and computing the sample size based on those factors. Sample size is influenced by expected effect size, study power, heterogeneity, error risk, and other variables. Dropouts from the sample during a study also impact sample size calculations. Proper determination of sample size is important for obtaining meaningful results and conducting ethical research.
Similar to Errors: types, determination and elimination (20)
BIRDS DIVERSITY OF SOOTEA BISWANATH ASSAM.ppt.pptxgoluk9330
Ahota Beel, nestled in Sootea Biswanath Assam , is celebrated for its extraordinary diversity of bird species. This wetland sanctuary supports a myriad of avian residents and migrants alike. Visitors can admire the elegant flights of migratory species such as the Northern Pintail and Eurasian Wigeon, alongside resident birds including the Asian Openbill and Pheasant-tailed Jacana. With its tranquil scenery and varied habitats, Ahota Beel offers a perfect haven for birdwatchers to appreciate and study the vibrant birdlife that thrives in this natural refuge.
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testimonies and modern exploration efforts.
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Magmatic iron-meteorite parent bodies are the earliest planetesimals in the Solar System,and they preserve information about conditions and planet-forming processes in thesolar nebula. In this study, we include comprehensive elemental compositions andfractional-crystallization modeling for iron meteorites from the cores of five differenti-ated asteroids from the inner Solar System. Together with previous results of metalliccores from the outer Solar System, we conclude that asteroidal cores from the outerSolar System have smaller sizes, elevated siderophile-element abundances, and simplercrystallization processes than those from the inner Solar System. These differences arerelated to the formation locations of the parent asteroids because the solar protoplane-tary disk varied in redox conditions, elemental distributions, and dynamics at differentheliocentric distances. Using highly siderophile-element data from iron meteorites, wereconstruct the distribution of calcium-aluminum-rich inclusions (CAIs) across theprotoplanetary disk within the first million years of Solar-System history. CAIs, the firstsolids to condense in the Solar System, formed close to the Sun. They were, however,concentrated within the outer disk and depleted within the inner disk. Future modelsof the structure and evolution of the protoplanetary disk should account for this dis-tribution pattern of CAIs.
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Signatures of wave erosion in Titan’s coastsSérgio Sacani
The shorelines of Titan’s hydrocarbon seas trace flooded erosional landforms such as river valleys; however, it isunclear whether coastal erosion has subsequently altered these shorelines. Spacecraft observations and theo-retical models suggest that wind may cause waves to form on Titan’s seas, potentially driving coastal erosion,but the observational evidence of waves is indirect, and the processes affecting shoreline evolution on Titanremain unknown. No widely accepted framework exists for using shoreline morphology to quantitatively dis-cern coastal erosion mechanisms, even on Earth, where the dominant mechanisms are known. We combinelandscape evolution models with measurements of shoreline shape on Earth to characterize how differentcoastal erosion mechanisms affect shoreline morphology. Applying this framework to Titan, we find that theshorelines of Titan’s seas are most consistent with flooded landscapes that subsequently have been eroded bywaves, rather than a uniform erosional process or no coastal erosion, particularly if wave growth saturates atfetch lengths of tens of kilometers.
1. • Types of errors
• Random
• Systematic errors
• Methods of detection and
elimination of systematic
errors
• Student‘s t-test
Topics
to be
covered
in this
slide
2. ERRORS
• It is defined as the
difference between the
observed or measured
value and the true and
accepted value in an
analysis.
• They usually affect the
accuracy and precision.
4. RANDOM ERRORS
• Errors whose magnitude
cannot be determined and
their effects cannot be
eliminated.
• These errors cause small
random variations in the
measured value when the
measurement is made a
number of times.
• Indeterminate errors will
affect the precision.
• These occur accidentally
hence they are called
5. SYSTEMATIC ERRORS
• Errors whose magnitude
can be determined and
their effects can be
eliminated are called
systematic errors.
• These errors cause the
value to differ from the
accepted and true value.
• These error affect the
accuracy of the results.
• Greater the error lesser
will be the accuracy
8. INSTRUMENTAL ERRORS
• These errors are
caused by the usage of
defective instruments
and instabilities in the
power supply.
• These are detected
and eliminated by
calibration
• Periodic calibration of
the instrument is
10. BY USING STANDARD
SAMPLE
• The best way of
determining this type
of errors is by doing
an analysis with the
standard reference
material.
• The standard
reference material is
to be synthesized or
bought from industrial
sources.
11. BY USING INDEPENDENT ANALYSIS
• If standard samples
are not available, a
second independent or
reliable method can
be performed parallel
to analytical method
being evaluated
12. VARIATION IN SAMPLE SIZE
• As the size of sample
increases , the effect
of systematic error
decreases.
• Hence this type of
error can be detected
and eliminated by
running the
experiment by
changing the sample
size.
13. PERSONAL OR OPERATIVE
ERRORS
• These errors are
caused by
carelessness ,
inattention physical
inability and a wrong
way of using
instruments.
• These can be reduced
by care and self
discipline and good
knowledge in handling
14. COMPARRISON OF
RESULTS
• The value obtained
from a set of results
are compared with
either the true value
or standard value.
15.
16. STUDENT’S -T - TEST
• Comparison of
experimental mean
with a true value.
• t=Іx-μІ√n/s
Where ,
x is the mean
μ is the true value
n is the number of
results
S is the standard
18. • The t value is related
to the t table which
provides the value of t
for a few degrees of
freedom.
• If the calculated value
of t is greater than
that of the values in
the t table then the
result is significant.
• If the experimental
value is less than that
of the given t table