4.2.3 11 - Reliability & Validity

Question 1

what is reliability in psychological research?

Answer 1

• reliability refers to consistency in measurement
• the same procedure should produce similar results when repeated

Question 2

how is reliability demonstrated through replication?

Answer 2

• the study is replicated using the same procedure
• similar results are found each time

Question 3

why does consistency indicate reliability?

Answer 3

• results do not fluctuate significantly
• the measure is stable and dependable

Question 4

when can a study be described as reliable?

Answer 4

• it uses a standardised procedure
• it produces the same results when repeated

Question 5

why are lab experiments considered the most reliable method?

Answer 5

• conducted in controlled conditions
• use standardised procedures
• minimise extraneous variables

Question 6

how do lab experiments improve reliability?

Answer 6

• random allocation to conditions
• use of control groups
• quantitative data is easy to analyse

Question 7

why are field experiments less reliable than lab experiments?

Answer 7

• extraneous variables cannot be fully controlled
• environment is less controlled

Question 8

why are natural experiments less reliable than lab experiments?

Answer 8

• the iv is naturally occurring
• researchers have no control over the iv

Question 9

what is internal reliability?

Answer 9

• consistency within a measure itself
• whether different parts of the test produce similar results

Question 10

what is external reliability?

Answer 10

• consistency of a measure over time
• whether the same results are found on different occasions

Question 11

what does the test-retest method measur

Answer 11

• external reliability
• consistency of results over time

Question 12

how does the test-retest method measure?

Answer 12

• the same questionnaire is given twice
• the same participants are tested after a time gap

Question 13

what does the split-half method measure?

Answer 13

• internal reliability
• consistency within the questionnaire

Question 14

how does the split-half method work?

Answer 14

• the questionnaire is divided into two halves
• responses from each half are compared

Question 15

what is inter-observer reliability?

Answer 15

• consistency between two or more observers
• agreement when recording the same behaviour

Question 16

how does researchers establish inter-reliability?

Answer 16

• observers agree on behaviour categories beforehand
• behaviours are clearly operationalised

Question 17

why must observers record behaviour independently?

Answer 17

• to avoid conformity
• to prevent observers influencing each other

Question 18

how is inter-observer reliability assessed after observation?

Answer 18

• observers compare their data sets
• a correlation between scores is calculated

Question 19

what indicates good inter-observer reliability?

Answer 19

• a strong positive correlation
• typically 0.8 or above

Question 20

why does good inter-observer reliability reduce bias?

Answer 20

• observer interpretations are consistent
• researcher bias is less likely to affect results

Question 21

how can reliability be improved in lab experiments?

Answer 21

• use controlled and standardised procedures
• operationalise the iv and dv

Question 22

how can reliability be improved in observations?

Answer 22

• use clear, observable behaviour categories
• ensure no overlap or ambiguity

Question 23

how can reliability be improved in questionnaires?

Answer 23

• use test-retest to check consistency
• replace open questions with closed questions

Question 24

how can reliability be improved in interviews?

Answer 24

• use the same interviewer
• use trained interviewers
• avoid leading or ambiguous questions

Question 25

what is validity in psychological research?

Answer 25

• whether findings are genuine and meaningful • whether the study measures what it intends to measure

Question 26

what is internal validity?

Answer 26

- whether changes in the dv are caused by the iv - extraneous variables are controlled

Question 27

what is external validity?

Answer 27

- whether findings can be generalised - applies beyond the research setting

Question 28

what is ecological validity?

Answer 28

- how realistic the task feels to participants - whether behaviour reflects real life

Question 29

what is temporal validity?

Answer 29

- whether findings are still relevant today - considers changes in society & culture

Question 30

what is face validity?

Answer 30

- whether a test looks like it measures what it should - judged at face value

Question 31

what is predictive validity?

Answer 31

- how well a test predicts future behaviour - links present performance to future outcomes

Question 32

what is concurrent validity?

Answer 32

- comparison with an established test - strong positive correlation indicates validity

Question 33

how can validity be improved in lab experiments?

Answer 33

- controlled conditions & standardisation - use of control groups

Question 34

what are investigator effects?

Answer 34

- researcher unintentionally influences results - behaviour or expectations affects participants

Question 35

how can investigator effects be reduced?

Answer 35

- use double-blind procedures - researchers do not know participants conditions

Question 36

what are demand characteristics?

Answer 36

- participants guess the aim of the study - behaviour becomes unnatural

Question 37

how can demand characteristics be reduced?

Answer 37

- disguise the aim of the study - use single-blind procedures

Question 38

how can validity be improve in observations?

Answer 38

- use covert methods where ethical - ensure behaviour categories are clear

Question 39

how can validity be improved in questionnaires?

Answer 39

- use lie scales - use reverse scoring