1. TuTh – 4:00-5:15 Psych 241 – Methods Lab section 03

2. Rough Drafts! Please hand in your rough drafts. Levi will have them ready for you on Tuesday. The final version will then be due on Thursday once you get them back.

3. Attendance When I call your name, please answer.

4. Papers/Rough Drafts Any questions about the papers? Sections: Title Page Abstract Introduction Method Results Discussion References Figures and/or graphs

5. Main Effects and Interactions Main Effect: Does being in different levels of a single IV (independent variable) lead to different outcomes on the DV(s) (dependent variables).? Example: Stroop task! Does being in different levels (having no labels compared to having incongruent labels) of a single IV (Incongruent Labels compared to No Labels) lead to different outcomes on the DVs (reaction time and errors)?

6. Main Effects and Interactions Interaction Effect: Does being in different levels of a single IV (independent variable) only lead to different outcomes on the DV(s) (dependent variables) depending on what level you are in on another IV (independent variable)? Example: Stroop task and reading history! Does being in different levels (No labels compared to Incongruent Labels) of a single IV lead to different outcomes on the DVs (reaction time and errors) depending on what level you are in (early reader or late reader) on another IV (Reading history)?

7. Main Effects and Interactions CHART NLINC Early Readers2335 Late Readers2342

8. Main Effects of Reading History CHART NLINC Early Readers2335 Late Readers2342 23 + 35 = 58. Divide by the two cells 58/2 = 29 23 + 42 = 65. Divide by the two cells 65/2 = 32.5 + +

9. Main Effects of Reading History 32.5 – 29 = 3.5. That shows that there is a main effect of early readers, in that early readers are faster overall than late readers. Now, what about having no labels compared to incongruent labels? Is there a main effect?

10. Main Effects of Labels CHART NLINC Early Readers2335 Late Readers2342 23 +23 = 46 46/2 = 23 + + 35 +42 = 77 77/2 = 38.5

11. Main Effects of Labels CHART NLINC Early Readers2335 Late Readers2342 + + 38.5 – 23 = 15.5 There is a main effect of labels. INC take longer than NL.

12. Interaction Effects CHART NLINC Early Readers2335 Late Readers2342 23 – 23 = 0, early and late readers aren’t different when they are responding to pictures with no labels + +

13. Interaction Effects CHART NLINC Early Readers2335 Late Readers2342 42 – 35 = 7, However, late readers are slower than early readers on incongruent labels + +

14. Interaction Effects: Graph

15. In-Class Assignment Split into groups or 3 or so! Course Packets: Do the problems on pages 96-99. Offer answers, or get called out randomly when you look the most vulnerable!

16. Survey Project Our next class project for your next paper will be a survey project of attitudes. Attitudes surveys help us understand how people feel and think. When creating an attitude survey, we want to think of something we would like to know more about.

17. Survey Project Then we want to think about what aspects there are to that idea. What questions do we need to ask to understand how someone feels about ____? We want to ask more than one question because the more questions we ask that touch on different aspects of how someone feels, the more likely it is we are getting the truth, and the more likely it is that we are getting at the complete idea that we are interested in.

18. Survey Project When creating a scale, we think of a large number of questions that we think “get at” how someone feels or thinks about a certain group or topic. We then create the scale and turn it into a survey, and when we get results, we can use the results to help us understand which questions really get at what we are interested in, and which ones seem to be more related to different ideas. We will talk about this more, so don’t worry if it doesn’t all make sense!

19. Homework Course Packet: read more about Main Effects and Interactions: pages 91-99 Course Packet: read about an attitude survey, pages 47-50 THERE WILL BE A QUIZ ON THE ATTITUDE SURVEY READING! Think of 3 attitude ideas that you would be most interested in making an attitude scale of and bring them in for Tuesday.

20. Contact Information ladelman@psych.umass.edu Tobin 626 Office hour: Tuesdays from 1-2pm