Chapter 5

Question 1

How does one determind the construct validity of a study?

Answer 1

By looking at the reliability and validity of a study

Question 2

What kind of evidence supports the construct validity of a measured variable

Answer 2

Scatterplots and correlation coefficients can be used to determine reliability by seeing how similar two people measured observations and re-test reliability as well as using r to see whether two items are similar and therefore correlated.

Question 3

How does one measure variables?

Answer 3

1. Self-reports: where people report on their attitudes, beliefs or behaviours
2. Observational measures: where raters record the visible behaviors of people or animals
3. Physiological measures: where researchers measure biological data such as heart rate, brain activity and hormone levels

Question 4

What is the difference between categorical and quantitative variables?

Answer 4

Variables are either operationalised to be categorical, where the cases are categories, or quantitative variables which have meaningful numbers

Question 5

Quantitative variables can be further classified into..

Answer 5

1. Ordinal scales
2. Interval scales
3. Ratio scales

Question 6

How do researchers determine whether a measure is reliable?

Answer 6

Researchers collect data to see whether the measure works consistently.

Question 7

What are the 3 types of measurement reliability?

Answer 7

1. Test-retest reliability - whether a sample gives a consistent pattern of scores at more than one testing
2. Interrater reliability - whether two observers give consistent ratings to a sample of targets
3. Internal reliability - when people answer similarly worded items in a consistent way
   *measurement reliability is necessary but not sufficient for establishing measurement validity

Question 8

How can measurement validity be established?

Answer 8

It can be established with subjective judgements (face validity - if a measure is subjectively considered to be a plausible operationalisation of the conceptual variable in question and content validity - a measure must capture all parts of a defined conceptual definition) or with empirical data

Question 9

What are the 2 kinds of measurement validities?

Answer 9

1. Criterion validity - requires collecting data that show a measure is correlated with expected behavioral outcomes
2. Convergent and discriminant validity - requires collecting data that show a measure is correlated more strongly with measures of similar constructs than with measurements of dissimilar constructs.

Question 10

What is the major difference between ordinal and interval/ratio scales?

Answer 10

Ordinal does not have numerals that have a set distance between them, rank 1 could be 10s faster or 1 hour faster, but it will still be shown as rank 1 and 2 without any meaningful difference

Question 11

What kind of evidence supports criterion validity?

Answer 11

Known-groups paradigm - where researchers see whether scores on the measure can discriminate among two or more groups whose behaviour is already confirmed

Question 12

When do you try to determine discriminant validity?

Answer 12

When you are looking at a concept that is similar but still different to another concept, and need to be able to differentiate the two measures