PSY 102 Lecture Notes - Lecture 3: Scatter Plot, Confounding, Random Assignment

• School: Ryerson University
• Department: Psychology
• Course: PSY 102
• Professor: Kristin Vickers

Document Summary

Confounding variable: a variable that interferes with the results of the study. Changes with the i. v and affects the dependent variable, You don"t know whether the affects are caused by the independent variable or the confounding variable, or both. In an ideal experiment, you want to say only the iv affects the dv. Both the iv (# hrs study) and the confounding variable can affect the dv (grade) To get rid of confounding variables, for example, control the # of sleep, or set up a second independent variables. Random assignment to groups: everyone in the experiment ends up in one of the groups by chance. Assuming that all individual difference variables (physical, intelligence, background) are being evenly distributed among groups so that groups are essentially equal to one another. The larger the population, the better the random assignment. It is only assumed that random assignment is doing its job. Random sampling: randomly picking people from the population in a survey.