Unit 3: Collecting Data

Sampling methods, observational studies vs. experiments, randomization, and bias

This section contains 4 topics with 0 subtopics, 12 practice problems and 36 flashcards. Each topic includes comprehensive written notes, worked examples with detailed solutions, and interactive lessons for hands-on practice.

Topics Covered

• Sampling Methods — Compare simple random sampling, stratified, cluster, and systematic sampling methods.
• Observational Studies vs Experiments — Distinguish between observational studies and experiments, and understand causation vs. association.
• Experimental Design — Design experiments using control, randomization, replication, and blocking.
• Bias in Sampling and Surveys — Identify sources of bias in sampling and surveys including voluntary response and convenience sampling.

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