Psychological Investigations G541 Revision www.holah.co.uk/page/ investigations www.psychblog.co.uk/powerpoints

The Exam! The exam is 1 hour long and you will have to answer three questions. This unit is 30% of your total AS psychology - paper marked out of 60. Although you will have to learn four sections for this paper, you will only be asked questions on three of the sections. Experiments Correlations Observations Self-Reports You will be asked questions about: the piece of research including strengths and weaknesses. the data produced by the research. to design your own research the strengths and weaknesses of this proposed research.

The exam is 1 hour long and you will have to answer three questions.

This unit is 30% of your total AS psychology - paper marked out of 60.

Although you will have to learn four sections for this paper, you will only be asked questions on three of the sections.

You will be asked questions about:

the piece of research including strengths and weaknesses.

the data produced by the research.

to design your own research

the strengths and weaknesses of this proposed research.

EXPERIMENTS Psychological Investigations

Psychological Investigations

Experiments Three types of experiments: Laboratory experiments Highly controlled / artificial Field experiments Controlled variables in a natural environment Quasi (natural) experiments We have no control over the independent variable – it’s ‘naturally’ occurring (eg Gender)

Three types of experiments:

Laboratory experiments

Highly controlled / artificial

Field experiments

Controlled variables in a natural environment

Quasi (natural) experiments

We have no control over the independent variable – it’s ‘naturally’ occurring (eg Gender)

Experiments Independent Variable (IV) Dependent Variable (DV) Confounding Variable : a variable that effects the DV Extraneous Variable : a variable that could affect the DV but has been controlled for so it doesn’t.

Experiments Extraneous Variables Participant Variables Independent Measures = Individual Differences Situational Variables Any feature of the experiment that could influence a participants behaviour Single Blind – Double Blind – Control Groups

Extraneous Variables

Participant Variables

Independent Measures = Individual Differences

Situational Variables

Any feature of the experiment that could influence a participants behaviour

Single Blind – Double Blind – Control Groups

Experiments Independent Measures Participants are only in one condition. Repeated Measures The same participants repeat the two conditions Condition 1 Condition 2 Condition 1 Condition 2 Counter balancing – alter order of Pp’s

Independent Measures

Participants are only in one condition.

Repeated Measures

The same participants repeat the two conditions

Experiments Matched Pairs – make two groups of participants as similar as possible. Condition 1 Condition 2 Male (Bob) 21 IQ = 105 Male (Richard) 21 IQ = 105 Female (Dawn) 25 IQ = 115 Female (Cara) 25 IQ = 115

Matched Pairs – make two groups of participants as similar as possible.

Evaluation of Experimental Designs Strength Weakness Independent Measures No Order Effects Fewer Demand Characteristics Individual Differences Repeated Measures No Individual Differences Order Effects (counter balancing) Matched Pairs Controls for Individual Differences Can be difficult and costly.

Experimental Methods ± Independent & Dependent Variables Confounding & Extraneous Variables Cause & Effect Types of Experiments Laboratory Field Quasi (natural) Independent Measures Repeated Measures Matched-Pairs Sampling Methods Opportunity Random Snowball Stratified Self-Selected Ethics Ecological Validity Reliability Validity

Experiments – Hypotheses Participants memory will be much worse when there is a distraction in the room than when there is no distraction. Participants memory will be much worse when there is a distraction in the room than when there is no distraction. How are we measuring memory? What’s better or worse? Higher / Lower? More / Less? What is the distraction? How are we manipulating it? Operationalising your hypothesis How have you manipulated your IV? How have you measured your DV?

Experiments – Hypotheses Participants memory will be much worse when there is a distraction in the room than when there is no distraction. Participants will remember significantly more words from a list of 20 presented for 60 seconds when they are in a room with no distractions than participants who are in a room where rock music is playing in the background.

Experiments – Hypotheses Participants who [ do something ] will be significantly [ faster/better/quicker etc ] at [ something ] than participants who [ do something else ]. There will be no significant difference between participants who [ do something ] and those who [ do something else ]. Any difference will be down to chance. Alternative Null

Experiments – Hypotheses Participants who [ do something ] will be significantly [ faster/better/quicker etc ] at [ something ] than participants who [ do something else ]. There will be a significant difference between participants who [ do something ] and those who [ do something else ]. 1Tailed 2Tailed

Key Terms - Experiments Laboratory Experiment Field Experiment Quasi Experiment Independent Variable Dependent Variable Confounding Variable Extraneous Variable Replication Cause and Effect Ecological Validity Alternative Hypothesis Demand Characteristics Ethics Independent Measures Repeated Measures Matched-Pairs Individual Differences Order Effects Counter Balancing Operationalising Hypothesis Null Hypothesis

Laboratory Experiment

Field Experiment

Quasi Experiment

Independent Variable

Dependent Variable

Confounding Variable

Extraneous Variable

Replication

Cause and Effect

Ecological Validity

Alternative Hypothesis

Demand Characteristics

Ethics

Independent Measures

Repeated Measures

Matched-Pairs

Individual Differences

Order Effects

Counter Balancing

Operationalising Hypothesis

Null Hypothesis

CORRELATIONS Psychological Investigations

Psychological Investigations

Correlation Positive Correlation Negative Correlation Zero Correlation Can’t infer causation – only relationships! Correlation Coefficients +1.0 Perfect Positive +0.8 Strong +0.2 Weak 0 Zero -0.2 Weak -0.8 Strong -1.0 Perfect Negative

Positive Correlation

Negative Correlation

Zero Correlation

Can’t infer causation – only relationships!

Correlation Coefficients

+1.0 Perfect Positive

+0.8 Strong

+0.2 Weak

0 Zero

-0.2 Weak

-0.8 Strong

-1.0 Perfect Negative

Correlation – Hypotheses There will be a significant [ direction ] correlation between [ variable 1 ] (measured by [ something ]) and [ variable 2 ] (measured by [ something ]) There will be no significant correlation between [ variable 1 ] (measured by [ something ]) and [ variable 2 ] (measured by [ something ]) Alternative. Null

Correlation – Hypotheses There will be a significant [ direction ] correlation between [ variable 1 ] (measured by [ something ]) and [ variable 2 ] (measured by [ something ]) There will be a significant correlation between [ variable 1 ] (measured by [ something ]) and [ variable 2 ] (measured by [ something ]) 1Tailed 2Tailed No Direction

Data Analysis Descriptive Statistics Summary of data to illustrate patterns and relationships – BUT can’t infer conclusions Inferential Statistics Statistical tests that allow us to make conclusions in relation to our hypothesis. eg. Mann-Whitney or Spearman’s Rho.

Descriptive Statistics

Summary of data to illustrate patterns and relationships – BUT can’t infer conclusions

Inferential Statistics

Statistical tests that allow us to make conclusions in relation to our hypothesis.

eg. Mann-Whitney or Spearman’s Rho.

Data Analysis Scattergram to show the Correlation between variable 1 and variable 2 Titles are VERY important. Title your axis, the integers and give the graph a title.

Data Analysis Descriptive Statistics Summary of data to illustrate patterns and relationships – BUT can’t infer conclusions Inferential Statistics Statistical tests that allow us to make conclusions in relation to our hypothesis. eg. Mann-Whitney or Spearman’s Rho.

Descriptive Statistics

Summary of data to illustrate patterns and relationships – BUT can’t infer conclusions

Inferential Statistics

Statistical tests that allow us to make conclusions in relation to our hypothesis.

eg. Mann-Whitney or Spearman’s Rho.

Data Analysis Nominal - measure of central tendency: mode Data in categories (finished, fell, started) Ordinal - measure of central tendency: median Data which are ranked or in order (1 st 2 nd 3 rd ) Interval - measure of central tendency: mean Precise and measured using units of equal intervals (1m54s, 1m59s, 2m03s) Measure of dispersion = range (Highest – Lowest)

Nominal - measure of central tendency: mode

Data in categories (finished, fell, started)

Ordinal - measure of central tendency: median

Data which are ranked or in order (1 st 2 nd 3 rd )

Interval - measure of central tendency: mean

Precise and measured using units of equal intervals (1m54s, 1m59s, 2m03s)

Measure of dispersion = range (Highest – Lowest)

Key Terms - Correlation Positive Correlation Negative Correlation Zero Correlation Causation Correlation Coefficient Operationalise Variables Hypothesis One-tailed Hypothesis Two-tailed Hypothesis Alternate Hypothesis Null Hypothesis Descriptive Statistics Inferential Statistics Scattergram Cause-and-effect

Positive Correlation

Negative Correlation

Zero Correlation

Causation

Correlation Coefficient

Operationalise Variables

Hypothesis

One-tailed Hypothesis

Two-tailed Hypothesis

Alternate Hypothesis

Null Hypothesis

Descriptive Statistics

Inferential Statistics

Scattergram

Cause-and-effect

SELF-REPORTS Psychological Investigations

Psychological Investigations

Self-Report Data Types Quantitative Data Number data: easy to analyse – no meaning Qualitative Data Describing meaning: difficult to analyse More valid – no interpretation needed

Data Types

Quantitative Data

Number data: easy to analyse – no meaning

Qualitative Data

Describing meaning: difficult to analyse

More valid – no interpretation needed

Self-Report Questionnaires Open Questions = Qualitative Data Closed Questions = Quantitative Data Fixed Choice (yes / no) Rating Scales (Likert-type Scales) Social Desirability & fibbing Response rates & leading questions Types of SR Hand Out Face-to-face Phone Email / Internet Postal

Questionnaires

Open Questions = Qualitative Data

Closed Questions = Quantitative Data

Fixed Choice (yes / no)

Rating Scales (Likert-type Scales)

Social Desirability & fibbing

Response rates & leading

questions

Self-Report Interviews Structured / Unstructured Interviews Demand Characteristics / Social Desirability Reliability – how consistent are the findings Validity – does the question measure what is claims to measure? Questionnaires: Split-Half Method Interviews: Replicate them Ask OPEN questions – more valid Conduct an observation of behaviour

Interviews

Structured / Unstructured Interviews

Demand Characteristics / Social Desirability

Reliability – how consistent are the findings

Validity – does the question measure what is claims to measure?

± Self Reports Interviews Structured Unstructured Data-Types Quantitative Qualitative Types of SR’s Postal / Mail Email / Web Handout Telephone Face-to-Face Sampling Opportunity Self-Selected Random Stratified Snowball Reliability & Validity Social Desirability Question Types Open / Closed Fixed Choice / Likert

Sampling General Population Sample Representative Sample Generalisations Sampling Techniques

Sampling Opportunity Sample People who are there at the time. Quick / Cheap / Easy Not representative Random Sample Each person in the GP has an equal chance of being chosen. Expensive and time consuming. Representative sample

Opportunity Sample

People who are there at the time.

Quick / Cheap / Easy

Not representative

Random Sample

Each person in the GP has an equal chance of being chosen.

Expensive and time consuming.

Representative sample

Sampling Self-Selected Participants volunteer to be in the sample following advert etc. Quick / Cheap / Easy Not representative What kind of person volunteers for a psychology experiment? Snowball Sampling One person tells others who tell others … Allows us to collect difficult to locate people Time consuming

Self-Selected

Participants volunteer to be in the sample following advert etc.

Quick / Cheap / Easy

Not representative

What kind of person volunteers for a psychology experiment?

Snowball Sampling

One person tells others who tell others …

Allows us to collect difficult to locate people

Time consuming

Key Terms - Self-Report Questionnaires Interviews Open Questions Closed Questions Social Desirability Response Rate Leading Questions Unstructured Interviews Quantitative Data Qualitative Data Likert Scales Fixed Choice Reliability Validity Split-half method Sampling Opportunity Sample Random Sample Self-selected Sample Stratified Sample Snowball Sample

Questionnaires

Interviews

Open Questions

Closed Questions

Social Desirability

Response Rate

Leading Questions

Unstructured Interviews

Quantitative Data

Qualitative Data

Likert Scales

Fixed Choice

Reliability

Validity

Split-half method

Sampling

Opportunity Sample

Random Sample

Self-selected Sample

Stratified Sample

Snowball Sample

OBSERVATIONS Psychological Investigations

Psychological Investigations

Observation Participant Observations Take part in what you’re observing Non-Participant Observations Just observe – no interaction Disclosed (overt) Observations Participants aware of observer Undisclosed (covert) Observations Participants unaware of observer Ethics ! Observer effect Act differently Objectivity?

Participant Observations

Take part in what you’re observing

Non-Participant Observations

Just observe – no interaction

Disclosed (overt) Observations

Participants aware of observer

Undisclosed (covert) Observations

Participants unaware of observer

Observation Structured Observation Coding scheme is used to record behaviour Quantitative data collected Unstructured Observation Researchers just record what’s going on Qualitative data collected (usually) Controlled Observations Researchers manipulate some variables Event Sampling Time Sampling

Structured Observation

Coding scheme is used to record behaviour

Quantitative data collected

Unstructured Observation

Researchers just record what’s going on

Qualitative data collected (usually)

Controlled Observations

Researchers manipulate some variables

Observation - Sampling Event Sampling Coding Scheme Researcher records an event every time it happens. If too many things happen at once it may be difficult to record everything. Time Sampling Researcher decides on a time and then records what is occurring at that time Some behaviours will be missed therefore the observation may not be representative.

Event Sampling

Coding Scheme

Researcher records an event every time it happens.

If too many things happen at once it may be difficult to record everything.

Time Sampling

Researcher decides on a time and then records what is occurring at that time

Some behaviours will be missed therefore the observation may not be representative.

Observation Reliability Difficult to replicate observation – confounding variables. Check consistency within observations with inter-rater reliability (≥ 0.8) Improve reliability by using good coding scheme Validity If participants know = low validity Observer bias = low validity Improve by using wider categories or single-blind technique Check validity by asking participants – self-report

Reliability

Difficult to replicate observation – confounding variables.

Check consistency within observations with inter-rater reliability (≥ 0.8)

Improve reliability by using good coding scheme

Validity

If participants know = low validity

Observer bias = low validity

Improve by using wider categories or single-blind technique

Check validity by asking participants – self-report

Ethics Consent Withdrawal Debriefing Deception Confidentiality Observation Protection Advice Colleagues

Consent

Withdrawal

Debriefing

Deception

Confidentiality

Observation

Protection

Advice

Colleagues

Key Terms - Observation Ecological Validity Non-participant Obs. Participant Obs. Undisclosed (covert) Disclosed (overt) Structured Unstructured Coding Scheme Controlled Observation Event Sampling Time Sampling Reliability Inter-rater Reliability Validity Categories Ethics Quantitative Data Qualitative Data

Ecological Validity

Non-participant Obs.

Participant Obs.

Undisclosed (covert)

Disclosed (overt)

Structured

Unstructured

Coding Scheme

Controlled Observation

Event Sampling

Time Sampling

Reliability

Inter-rater Reliability

Validity

Categories

Ethics

Quantitative Data

Qualitative Data

WWW.PSYCHBLOG.CO.UK/POWERPOINTS © 2008 Jamie Davies Shared under the Creative Commons Attribution-Non-Commercial-Share Alike 2.0 Licence. www.creativecommons.org

© 2008 Jamie Davies