Section 1 - Instruction

You've mastered reading data, but here's where things get tricky: just because two things happen together doesn't mean one causes the other.

This confusion leads to some of the worst evidence mistakes you'll encounter.

Engagement Message

Can you think of two things that often happen together but don't cause each other?

Section 2 - Instruction

Correlation means two things tend to move together. When ice cream sales rise, drowning incidents also rise. They're correlated - they follow similar patterns.

But correlation is just about timing and patterns, not cause and effect.

Engagement Message

What do you think actually explains both ice cream sales and drowning incidents rising together?

Section 3 - Instruction

Causation means one thing directly makes another happen. Turning your car key causes the engine to start. Causation creates correlation, but correlation doesn't prove causation.

This is where most people get fooled by evidence.

Engagement Message

Which is stronger evidence: correlation or causation?

Section 4 - Instruction

Why do we confuse them? Our brains are pattern-seeking machines. When we see two things happen together repeatedly, we instinctively think one causes the other.

This mental shortcut worked for our ancestors but fails with complex modern data.

Engagement Message

What's an example where this mental shortcut might mislead you?

Section 5 - Instruction

Enter confounding variables - hidden factors that cause both things you're observing. In our ice cream example, hot weather causes both more ice cream sales AND more swimming (leading to drowning).

The real cause is lurking in the background, unseen.

Engagement Message

What might be the hidden factor if "people who own books live longer"?

Section 6 - Instruction
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