Types of Experiments

Observational Study vs Designed Experiments

This video may be, at first glance, about observational and designed experiments. But really it's a how-to for your future career as a data-mastering statistics master who will not -- who dare not -- do experiments that suck (statistically speaking). God speed.

Prospective (Longitudinal or Cohort) vs Cross-Sectional vs Retrospective Studies

With these studies, it's mostly a matter of timing. Discuss.

Double-Blind, Placebo-Controlled Study

This term mostly applies only to medical research trials, such as investigating new drugs and whatnot, but it's illustrative to show you just how awesomely statistical a study can be. No confounding variables here!