Study design

Sampling and observational studies

Learn

Identifying a sample and population
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Generalizabilty of survey results example
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Examples of bias in surveys
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Example of undercoverage introducing bias
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Identifying bias in samples and surveys
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Practice

Identifying the population and sampleGet 3 of 4 questions to level up!
Generalizability of resultsGet 5 of 7 questions to level up!
Bias in samples and surveysGet 5 of 7 questions to level up!

Sampling methods

Learn

Techniques for generating a simple random sample
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Techniques for random sampling and avoiding bias
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Practice

Simple random samplesGet 3 of 4 questions to level up!
Sampling methodsGet 5 of 7 questions to level up!

Types of studies (experimental vs. observational)

Learn

Types of statistical studies
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Worked example identifying experiment
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Worked example identifying observational study
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Observational studies and experiments
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Practice

Observational studies versus experimentsGet 5 of 7 questions to level up!

Experiments

Learn

Introduction to experiment design
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The language of experiments
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Principles of experiment design
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Random sampling vs. random assignment (scope of inference)
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Matched pairs experiment design
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Invalid conclusions from studies example
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Can causality be established from this study?
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Practice

Experiment designsGet 3 of 4 questions to level up!
Finding errors in study conclusionsGet 3 of 4 questions to level up!
Experiment design considerationsGet 3 of 4 questions to level up!

About this unit

Statistics is all about forming questions and gathering data to explore those questions. This unit covers sampling and survey methods, observational studies, and basic experiment design.