FILE SELECTED // FILE 00
Statistical Power
“A study may miss a signal because its flashlight was too weak.”
01 / SUMMARY
In short
Power is the probability that a test rejects the null for a specified effect and design when the considered alternative is true. It generally rises with larger samples and stronger signals.
03 / SCENE
In the wild
With few participants, two treatments may look indistinguishable even when a moderate difference exists.
04 / LIMIT
The limit
Low power does not automatically turn a nonsignificant result into evidence for a hidden effect.
FINAL NOTE
What remains
Plan sensitivity before collecting data and report which magnitudes the study could detect.