Psychology 2800E Lecture Notes - Lecture 6: Microwave Popcorn, Line Graph

• School: Western University
• Department: Psychology
• Course: Psychology 2800E
• Professor: Glen Gorman

Document Summary

L7: experiments with more than 1 independent variable con"t . Interpreting results form factorial designs: main effects. Overall effect of one iv at a time. Easiest to detect by looking at table of means. Main effects you"re taking an average either across or down (not both: interactions. Interactions occur in an experiment with two ivs. Easiest to detect by looking at line graphs. >when lines are not parallel > there probable is an interaction. See interaction to see if theres a difference between the size of the bottle and the price. >main effect=age (since lines start at different points) Graph 2=one bar is different from all others so it shows an interaction as graph 1. > there is a main effect for iv-b such that level b1 is higher than level b2. >when describing a main effect for iv-b, you do not mention iv-a! (and vice- versa)