When a researcher rejects the Null Hypothesis (H₀) in his/her study and…
2020
When a researcher rejects the Null Hypothesis (H₀) in his/her study and accepts an alternate Hypothesis (H₁), what type of error is likely?
- A.
Type I error
- B.
Type II error
- C.
Both Type I and Type II error
- D.
Neither Type I nor Type II error
Show answer & explanation
Correct answer: A
CONCEPT
In hypothesis testing, a Type I error means rejecting a true null hypothesis. A Type II error means failing to reject the null hypothesis when the alternative is actually true.
So the distinction depends on the decision about H0: rejection points to Type I risk; non-rejection points to Type II risk.
APPLICATION
Here the researcher rejects H0 and accepts H1. In exam shorthand, that decision is the false-positive kind of error: concluding that an effect exists when the null position should have been retained.
CONTRAST
Type II error describes missing an effect by not rejecting H0, so it does not fit a stem where H0 has been rejected.
Both Type I and Type II error mixes two opposite decision errors, while the stem describes one decision path.
Neither Type I nor Type II error would deny the standard hypothesis-testing classification, which is not appropriate here.
RESULT
The likely error is Type I error.