Intermediate level · Module 5 of 6 · 15 guided hours
Testing Changes and Causal Thinking
Judge whether a change caused an improvement, using fair comparisons and simple tests.
Learning objectives
- Distinguish correlation from causation
- Design simple before-after and comparison-group tests
- Interpret test results with appropriate caution
Topics
- correlation and causation
- confounding factors
- before-after comparisons
- comparison groups
- pilot tests
- sample size and noise
Lessons
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Lesson 1 Correlation, Causation and Confounders
Avoid concluding that one thing caused another just because they moved together.
correlationcausationconfounderreverse causation
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Lesson 2 Designing Fair Tests
Design pilots that can show whether a change works.
before-aftercomparison grouprandom assignmentpilot
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Lesson 3 Interpreting Test Results
Read pilot results with care, considering noise, size and practical importance.
difference between groupsnoisesample sizepractical significance
Practical activity
Design a pilot to test whether SMS reminders increase repeat purchases or clinic attendance, and analyse provided pilot results.
Expected outcomes
- Sound judgement about what caused results
- Practical test designs
Assessment
Test design and analysis marked on fairness, logic and caution in conclusions.
Taught live by an instructor — online or in person. Free course lessons are for self-study and do not lead to a certificate — see registration options.