📊 What Does “Correlated” Actually Mean?
We’ve all heard it: “Correlation doesn’t imply causation.” But what exactly IS correlation?
🍕 Countries that eat more pizza tend to have higher math scores. 🦈 More sunglasses sold → more shark attacks.
Does pizza improve math skills? Of course not! But why do these correlations exist?
🔢 Correlation is a precise mathematical measurement, not just a vague feeling of “they’re related.” The Pearson coefficient measures how consistently two variables move together, on a scale from -1 to +1:
- 📈 +1: perfect positive relationship
- ➡️ 0: no linear relationship
- 📉 -1: perfect negative relationship
⚠️ Common misunderstandings:
- Assuming causation where there’s only correlation
- Ignoring hidden variables (temperature explains both sunglasses sales AND shark attacks)
- Forgetting that correlation only detects linear relationships
💡 Correlation is a signal, not an explanation. It says: “Something interesting might be happening here.” Further investigation is what provides the why.
💡 Explanation in a nutshell#
Imagine that every time it rains, umbrella sales go up. That’s correlation: two things moving together. But rain doesn’t magically “cause” umbrella sales — what happens is that rain leads people to buy them. Correlation just tells you there’s a pattern; it doesn’t tell you why that pattern exists. To find the “why,” you need to investigate further.
More information at the link 👇
