1. M EASUREMENT AND D ATA A NALYSIS

2. W HAT TO M EASURE —V ARIETIES OF B EHAVIOR Psychologist can measure unlimited number of behaviors to observe the psychological construct in question overt behavior (e.g., rats running through a maze) self-report (e.g., college students filling out an attitude survey) to recordings of physiological activity (e.g., blood pressure, galvanic skin response)

3. W HAT TO M EASURE —V ARIETIES OF B EHAVIOR Attention Span A study on ‘‘span of apprehension in schizophrenic patients as a function of distractor masking and laterality’’ (Elkins, Cromwell, & Asarnow, 1992) investigated attention-span limitations in patients diagnosed with schizophrenia. The behavior measured was whether or not the participants could accurately name the target letters in different circumstances. Compared with nonschizophrenic controls, the schizophrenic patients did poorly when asked to identify target letters appearing in an array of distracting letters.

4. W HAT TO M EASURE —V ARIETIES OF B EHAVIOR Burnout A study on the ‘‘effects of respite from work on burnout: vacation relief and fade-out’’ (Westman & Eden, 1997) looked at the effects of a vacation on perceived stress and degree of burnout for clerical workers in an electronics firm. On three different occasions, before, during, and after a vacation, researchers measured (a) perceptions of job stress with eight items from a survey instrument called the ‘‘Job Characteristics Questionnaire,’’ and (b) job burnout with a twenty-one-item ‘‘Burnout Index.’’ Participants also filled out a ‘‘Vacation Satisfaction Scale.’’ Initially, high stress and burnout scores dropped precipitously during the vacation, but the effect was very short-lived. By three weeks after the vacation, stress and burnout levels were back at the pre-vacation level.

5. W HAT TO M EASURE —V ARIETIES OF B EHAVIOR Honesty A study on the ‘‘effects of deindividuation on stealing among Halloween trick-or-treaters’’ (Diener, Fraser, Beaman, & Kelem, 1976) observed the candy- and money-taking behavior of children in a field study during Halloween night. The behavior observed (from behind a screen by an experimenter) was whether children took extra amounts of candy, and/or took money that was in a nearby bowl, when the woman answering the door briefly left the room. When given an opportunity to steal, the children were most likely to succumb to temptation when (a) they were in groups rather than alone, and (b) anonymous (i.e., not asked their name) rather than known.

6. W HAT TO M EASURE —V ARIETIES OF B EHAVIOR Arousal A study of ‘‘task-related arousal of Type A and Type B persons’’ (Holmes, McGilley, & Houston, 1984) compared two types of subjects (A and B) on a digit span task (listen to a list of numbers, then repeat them back accurately) that varied in difficulty. While performing the task, several physiological measures of arousal were taken, including systolic and diastolic blood pressure. Compared with more laid-back Type B subjects, hard-driving type A subjects showed elevated blood pressure, especially when the task increased in difficulty.

7. W HAT TO M EASURE —V ARIETIES OF B EHAVIOR How a researcher decide on a certain measure, instead of others, to make a psychological construct observable Previous studies Modifying comonly used measures Be creative: use an old measure for a new construct By this way, psychologist can study even seemingly unemprical questions Do preverbal infants understand the concept of gravity? Can you demonstrate that people use visual images?

8. W HAT TO M EASURE —V ARIETIES OF B EHAVIOR Research Example 1—Habituation Do preverbal infants understand the concept of gravity? We know that infants do “preferential looking” and habitation preferential looking: infants prefer to look at events that are new to them (Spelke, 1985) Habituation: When a stimulus is presented repeatedly, infants lose interest (i.e., they stop looking)

9. W HAT TO M EASURE —V ARIETIES OF B EHAVIOR Research Example 1—Habituation Kim and Spelke (1992) compared 5- and 7-month-olds in terms of their understanding of gravity Two Things New 1.Going up 2.Slowing Down OneThings New 1.Going up

10. W HAT TO M EASURE —V ARIETIES OF B EHAVIOR Research Example 2—Reaction Time Can you demonstrate that people use visual images? Shepard and Metzler (1971) asked participants to decide whether each right-hand object of each pair be the same as the left-hand object, but merely rotated to a different position

11. E VALUATING M EASURES How can we decide if one measure is better than others? Reliability It is about whether measurements are consistent in repeating remeasures Validity It is about whether the measurement measures what is aimed to be measured

12. E VALUATING M EASURES All the variability in the DV scores Variability in DV caused by the IV Variability in DV caused by error This is spread randomly across the scores of both conditions This affects the scores of one condition differently from the other Random error Systematic error Systematic error

13. E VALUATING M EASURES Reliability: Consistency in Measurement Inconsistent Measures RT1= 850ms, RT2=370ms, RT3=1120ms Consistent Measures RT1= 850ms, RT2=860ms, RT3=840ms Two Kinds of Reliability Consistency in Time Internal Consistency Reliability is a statistical question.

14. E VALUATING M EASURES Validity: Measuring what we want to measure Validity is a theoretical question A single study is not enough to decide whether a measure is valid or not.

15. E VALUATING M EASURES Types of Validity Face Validity: Do the outlook of the measurement look valid? Content Validity: Are the items or tasks of the measurement valid? Criterion validity: Are the measures consistent with a already known valid measure Predictive Validity: Can measure predict future behavior? Construct Validity: Can the measure in question measure the psychological construct Convergent Validity Divergent Validity

16. E VALUATING M EASURES Bandura (1986): self-efficacy: judgments of [our] capabilities to organize and execute courses of action required to attain designated types of performances Locus of control (LOC) concerns our personal beliefs about the causes of what happens to us self-confidence: Confidence is a nondescript term that refers to strength of belief but does not necessarily specify what the certainty is about.

17. E VALUATING M EASURES Mayer & Frantz (2004): Connectedness to Nature Scale (CNS) Sample items I think of the natural world as a community to which I belong I have a deep understanding of how my actions affect the natural world My personal welfare is independent of the welfare of the natural world For Construct Validity CNS NEP (‘‘New Ecological Paradigm’’) scale Ecological behaviors (e.g., how often they turned off the lights in vacant rooms), Scholastic aptitude: SAT a measure of social desirability (scoring high on this test means wanting to make oneself look good)

18. S CALES OF M EASUREMENT We are quite familiar with four kinds of scales Nominal Ordinal Interval Ratio Let’s work on some examples to get sure that you got the idea

19. S CALES OF M EASUREMENT Comparing male and female joggers, who is more likely to run during the morning and who is more likely to run in the evening? If a child ranks five toys and is given the one ranked third, will the ranking for that toy go up or down after the child has played with it for a week? Jesse is interested in sex differences in shyness and gives a 15-item shyness test to groups of men and women. Each item has a statement (e.g., I have difficulty talking to strangers) that asks responders to rate on a scale from 1 (strongly disagree) through 5 (strongly agree). How do young versus old people rank ten movies that vary in the levels of the amount of sex and aggression found in them? When you change answers on a multiple-choice test, are you more likely to improve your score or hurt it? Kruger, Wirtz, and Miller (2005) right → wrong: 25% Wrong → right: 51% wrong → wrong: 23%

20. S TATISTICAL A NALYSIS You are very familiar with these issues, so I assume that you can answer any question related to statistics correctly in the exam