1. 1 Round up - Qual and Quant Why have two types of research methodologies? Don’t replace each other we will always need statistics Each has its own place make sure you use the right type in the right circumstances

2. 2 Why use quant? causes/relationships = PREDICITON can predict changes, etc (clinical, legal, aviation, etc etc etc) Generalization to the population is important will my cure for AIDS for for everyone?

3. 3 Why use qual? Aim: to know what something “is like” feminists, educationalists, activists Can express things empathically The findings are not generalizable silly to talk about the average of “what its like”

4. 4 Using qual when you shouldn’t Gee, measuring this variable is too hard, so I’ll just get a “feel” for the relationship by asking people what it was like tells you nothing - numbers are at the heart of prediction no numbers, no generalization

5. 5 Using quant when you shouldn’t I think the media is racist. I will count the number of racist words used in newspaper and TV to prove all the media is racist Predicting doesn’t apply to everything Sometimes you can’t generalize not all newspapers are racist

6. 6 Who is going to read it? Both types require special knowledge to interpret Qual research seems understandable by anyone Remember the “Racism in the media” scandal? Know the limits of the research types.

7. 7 Psychometrics Aim: measure aspects of the psychology of a single person don’t care about populations - just old Bob by himself Why measure only a single person? Employment selection Diagnosis Evaluation

8. 8 A brief history of psychometrics Idea of testing people for selection ideas of “tests from the gods” in mythology ancient Chinese (2200 BC) “Scientification” occurred in the late 1800s Galton and Cattell (RT) Binet & Simon: intelligence testing in France (schools)

9. 9 In come the Americans Goddard: Detection of “feebleminded” immigrants at Ellis Island (1910) Army tests (officer selection) - Yerkes 1916 Alpha test (verbal test) Beta test (non verbal) After the war: aptitude testing (for any job!)

10. 10 The basic idea of testing We can’t measure psychological variables directly - They don’t exist! Psychometrics introduces the idea of a behaviour domain We can think of many things related to any psychological phenomenon All of these things together are the behaviour domain What is the behaviour domain of intelligence?

11. 11 Behaviour domains The things in the domain are very specific The list of a behaviour domain can be very long - infinately long, maybe? We want to know that a person displays most of these behaviours - but we can’t! Similar to the problem of research with populations and samples!

12. 12 Sampling the behaviour domain In research, to talk about populations we talked about samples (and could generalize) Psychometrics does the same - we want to talk about the entire behaviour domain, but we will use only a sample of these behaviours Each “question” in a test is a “subject”

13. 13 Sampling the domain: Example We begin by thinking of as many members of the behaviour domain as possible Randomly select a few of them That is the test!

14. 14 Research and psychometrics This similarity (overlap) is useful we can use our methodology knowledge to help make better tests We can talk about “reliability” and “validity” of tests to ensure we are making good tests. Reliability: is the test measuring accurately? Validity: is the test measuring only what it claims to measure?