Decision (action) | Null is true (not guilty) | Null is false (guilty) |
Reject the null hypothesis (convict) | Type
I error (convict the innocent) level of statistical significance, α |
Correct decision (convict the
guilty) power of the test, 1 - β |
Retain the null hypothesis (acquit) | Correct decision (acquit the innocent) | Type II error (acquit the guilty) chance of Type II error, β |
small effect | .00 to .20 |
medium effect | .20 to .50 |
large effect | .50 and higher |