PSYCH-225 Lecture Notes - Lecture 2: Control Key, Internal Validity, Dependent And Independent Variables
Document Summary
Measure effect on a dependant variable. Random assignment key- subjects are randomly assigned to the independent variable groups. Eliminates bias- anything that could cause a difference in the independent variable is equally likely in all groups. Control key- control over the environment so that everything about the groups are identical except for the one thing being tested (usually conducted in a lab to keep environment the same) Standardization- everything that happens to each person needs to be exactly the same (i. e. giving instructions in an experiment) Measuring the variables and how they relate to one another. Range of correlation between -1 and +1. Positive correlation- both variables go up or both go down. Perfectly correlated- vary by one whole unit. Negative correlation- one variable goes up as the other goes down (inversely related) Study time vs. number of test errors. Correlation of zero- not systematically correlated, unrelated to one another.