STAB22H3 Lecture Notes - Lecture 2: Block Design, Random Assignment, Teaching Method

• School: UTSC
• Department: Statistics
• Course: STAB22H3
• Professor: Mahinda Samarakoon

Document Summary

An observational study observes individuals and measures variables of interest but does not attempt to influence the response. An experiment imposes a treatment on individuals in order to observe their response. observational studies are valuable for discovering trends and possible relationships. however, it is not possible for observational studies to demonstrate a causal relationship. when our goal is to understand the cause and effect, experiments are the only source of fully convincing data. Researchers believe that unmarried men are more likely to suffer from clinical depression than married men. Look at a bunch of men suffering from depression, find out if they are married or not. Suppose that more men suffering from depression are unmarried. Maybe: but this is only an association, not cause and effect. This is an example of an observational study. Assesses association but not cause and effect (like correlation). May help identify variables that have an effect.