COMM 1 Lecture Notes - Lecture 13: Observational Error, Caffeine

• School: Irvine Valley College
• Department: Communication Studies
• Course: COMM 1
• Professor: Rybold

Document Summary

Main effects the effect of iv individually on the dv. E. g. , (for the 2x2: effects of music and caffeine on learning) Main effect for music: greater learning (higher test scores) when studying without music than with (i. e. music worsens learning) Main effect for caffeine: greater learning (higher test scores) when studying with caffeine than without (i. e. caffeine improves learning) How would you operationalize caffeine? starbucks and decaf, need a placebo. Factorial designs (continued) test for the effects of multiple variables. Main effect: effect that one of the iv has on the dv (like a separate study for each variable) interaction effect: unique effect of the combination of ivs. Caffeine reduces learning only when combined with listening to music. Music increases learning when you don"t have caffeine and caffeine increases learning when you don"t listen to music. Identifying effects to see if there are main effects, compare marginal means of dv.