PSYC 305 Lecture Notes - Lecture 3: Asteroid Family, Effect Size, Tachykinin Receptor 1

• School: McGill University
• Department: Psychology
• Course: PSYC 305
• Professor: Matthew Dean Graham

Document Summary

Understand the characteristics and concepts underlying ancova. Compute and interpret results of ancova, including adjusted means and multiple comparison procedures. Understand and evaluate the assumptions of ancova. Aim is to evaluate the effect of the main experimental manipulation while controlling for the effects on another variable. In other words, ancova is a form of statistical control developed specifically to reduce unexplained error variation (error, residual) By merging anova with linear regression, ancova controls for the effects that the covariate(s) (what we aren(cid:495)t going to be studying(cid:524) may have on the outcome (cid:523)dv(cid:524) Ancovas look at a continuous extraneous variable and how it affects the dv first: by doing that, we are taking extra information into consideration, by knowing this extra info, it will reduce unexplainable variability. Questionnaires: demographics are a way to study covariance that helps explain some variability in the dv, may or may not affect dv. If affects dv and affects both groups differently, extraneous becomes a confound.