Association versus causation: coincidence, confounding and common response

What this note covers

1. The limit of everything you have calculated so far
2. What the syllabus means by causal
3. The four possible explanations for an observed association
4. Confounding: effects that cannot be disentangled
5. Common response: a third variable driving both
6. Coincidence and reversed direction
7. Writing the answer that earns the marks
8. How this is examined in the WACE paper

8 sections · 12 key terms & formulas · 6 common mistakes