A result both ideas predict decides nothing
- The idea
- Predict
- See it
- Why
- Check
The idea
“It matches my hypothesis, so it supports mine over the other.”
A result that matches your idea feels like proof. If the other idea predicts it too, it can't favor yours.
The short version
The mistake: It matches my hypothesis, so it supports mine over the other.
What's actually true: Evidence favors one hypothesis only when the other one predicts a different result.
- A finding supports one hypothesis over another only if the two predict different results.
- A common garden experiment grows plants from different places in the same conditions. Any height gap left points to different alleles.
On the exam: If the other hypothesis predicts the same result, it can't decide between them.