PSYCO104 Lecture Notes - Lecture 7: Dependent And Independent Variables

• School: University of Alberta
• Department: Psychology
• Course: PSYCO104
• Professor: James Farley

Document Summary

Involve administering questionnaires or interviews (e. g. political polls) Advantages: efficient way to collect lots of data, can gauge changes across time. 1936 us presidential election example: nearly 2 million surveyed, results predicted a landslide win for. Names obtained using telephone directories car registrations, car registrations, and magazine subscription lists. This created a sample biased towards wealthier americans. Hould"(cid:448)e (cid:272)reated a sa(cid:373)ple of all i(cid:374)(cid:272)o(cid:373)es. Researchers measure (at least) two variables to determine if they are statistically related (ex. diet affecting longevity) Goal is to determine whether an association exists between variables. Correlations are mathematically described by a correlation coefficient: range from -1. 0-+1. 0, sign indicates direction, absolute value indicates strength. Positive correlation: as x increases, y also decreased, vice versa. Negative correlation: as x increases, y decreased, vice versa. Three main characteristics of experiences: a variable is manipulated (independent, measure dependent variable. 2: control factors that might influence results.