Hypothesis Testing Flashcards
7 cards from real AP practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Hypothesis Testing flashcards as text
A researcher conducts a two-sided t-test and obtains a p-value of 0.03. Which conclusion is most appropriate at the α = 0.05 level?
Answer: Reject H₀; the results are statistically significant.
Since 0.03 < 0.05, we reject H₀ and conclude the results are statistically significant at the 5% level.
In a hypothesis test, a Type II error occurs when you:
Answer: Fail to reject a false null hypothesis.
A Type II error (β) is failing to reject H₀ when H₀ is actually false — missing a real effect.
The power of a hypothesis test is best described as:
Answer: 1 minus the probability of a Type II error.
Power = 1 − β, the probability of correctly rejecting a false null hypothesis.
Which of the following actions will INCREASE the power of a hypothesis test, all else equal?
Answer: Increasing the sample size.
Larger samples reduce variability, making it easier to detect a true difference and thus increasing power.
A one-proportion z-test requires which condition regarding expected counts?
Answer: np ≥ 5 and n(1−p) ≥ 5 using the null proportion.
For a z-test on proportions, both np₀ and n(1−p₀) must be at least 10 (some curricula use 5) to ensure the sampling distribution is approximately normal.
A paired t-test is preferred over a two-sample t-test when:
Answer: Observations in the two groups are naturally matched or related.
Paired t-tests account for within-pair correlation by analyzing differences, reducing extraneous variability.
If you reduce α from 0.05 to 0.01 without changing anything else, what happens to the probability of a Type II error?
Answer: It increases.
Lowering α makes it harder to reject H₀, so the probability of failing to reject a false H₀ (Type II error) increases.