1. Measurement

2. Proposal Second Draft  Title Page  Introduction  Methods Section Participants Materials Procedure  Appendix IRB Form Consent Form Debriefing Statement Study Materials

3. Measurement Measurement – the process of assigning numbers to objects or events according to rules (Linn & Gronlund, 1995). Psychological Measurement – concerned with evaluating individual differences in psychological constructs.

4. Levels of Measurement Nominal - Classifies objects into categories (e.g., gender) Ordinal -Orders objects along a given dimension (e.g., rank order) Interval -Measures “how much” of a variable is present using equal distances between scale points  May have a zero point that is arbitrary E.g., zero degrees Fahrenheit Ratio -Has properties of all three previous scales plus a true zero point

5. Evaluating the Quality of Measures Reliability  Test-retest  Interrater  Internal consistency Validity  Concurrent  Discriminant

6. Types of Scales Likert  Most common Has properties we need for data analysis Guttman Thurstone

7. Guttman Scale The purpose of Guttman scaling is to establish a one- dimensional continuum for a concept you wish to measure. The scale is organized so that a respondent who agrees with any specific question in the list will also agree with all previous questions. INSTRUCTIONS: Place a check next to each statement you agree with. _____ I would permit a child of mine to marry an immigrant. _____ I believe that this country should allow more immigrants in. _____ I would be comfortable if a new immigrant moved next door to me. _____ I would be comfortable with new immigrants moving into my community. _____ It would be fine with me if new immigrants moved onto my block. _____ I would be comfortable if my child dated a new immigrant.

8. Thurstone Unidimensional scaling method You can give it to a participant and ask them to agree or disagree with each statement. To get that person's total scale score, you average the scale scores of all the items that person agreed with. Generate statements that describe specific attitudes that people might have towards persons with AIDS. Statements are rated in terms of favorability in attitudes (e.g, 1-11). Statements are then selected for final scale based on ratings  Statements should reflect each level of rating People with AIDS are like my parents (6) Because AIDS is preventable, we should focus our resources on prevention instead of curing (5) People with AIDS deserve what they got. (1) Aids affects us all (10) People with AIDS should be treated just like everybody else. (11) AIDS will never happen to me. (3) It's easy to get AIDS (5) AIDS doesn't have a preference, anyone can get it (9) AIDS is a disease that anyone can get if they are not careful (9) If you have AIDS, you can still lead a normal life (8) AIDS is good because it helps control the population. (2) I can't get AIDS if I'm in a monogamous relationship. (4)

9. 6 5 1 10 11 3 5 9 8 2 4 6+5+10+11+9+9+8+4=62 62/8 =7.75

10. Irritation Scale Not at All A Little BitModerately Quite a BitExtremely irritated or annoyed?12345 furiously angry?12345 mad?12345 so angry you felt like hitting the assistant? 12345 During the experiment, how much did the assistant make you feel the following:

11. Creating Scale Scores SubjectConditionItem 1Item 2Item 3Item 4 Mean Score 1334533.75 2223232.5 3112121.5 SubjectCondition Mean Irritation Score 133.75 222.5 311.5