STAT151 Chapter Notes - Chapter 11: Dependent And Independent Variables, Blind Experiment

• School: University of Alberta
• Department: Statistics
• Course: STAT151
• Professor: Omar Rivasplata

Document Summary

Researchers simply observe (e. g. did not assign students to music educaion, but simply observe them) Retrospecive study: examines the past (e. g. ideniied students who studied music and then collected data on their past grades. ) Prospecive study: watches for future outcomes (e. g. ideniied students who study music and collect data as events unfold. ) Study design that allows us to prove a cause-and-efect relaionship. Experiments need: an explanatory variable to manipulate (called a factor) and a response variable to measure. Experimental units: are individuals on whom we experiment (called subjects of paricipants) Diferences that is larger than we"d get just from the randomizaion alone. Group assigned to a null treatment or to the best available alternaive treatment. Control group: experimental units to whom it applies. Used to avoids bias that might result from knowing what treatment was assigned. Single blind: when every individual in either the subjects or those who evaluate the results are blinded.