Statistics Hypothesis Testing & Inference

Question 1

What does the null hypothesis (H₀) typically represent in a statistical test?

Accepted Answer

No effect or no difference exists in the population

Answer

A significant difference exists in the population

Answer

The researcher's prediction is correct

Answer

The sample statistic equals the parameter

Question 2

What is a Type I error in hypothesis testing?

Accepted Answer

Rejecting a true null hypothesis

Answer

Failing to reject a false null hypothesis

Answer

Using the wrong test statistic

Answer

Setting alpha too low

Question 3

If a p-value is 0.03 and the significance level α is 0.05, what conclusion is drawn?

Accepted Answer

Reject the null hypothesis

Answer

Fail to reject the null hypothesis

Answer

Accept the null hypothesis

Answer

Increase the sample size

Question 4

Which test is appropriate for comparing the means of two independent groups?

Accepted Answer

Two-sample t-test

Answer

Paired t-test

Answer

Chi-square test

Answer

ANOVA

Question 5

What does statistical power represent?

Accepted Answer

The probability of correctly rejecting a false null hypothesis

Answer

The probability of making a Type I error

Answer

The width of a confidence interval

Answer

The effect size of a study

Question 6

What is a one-tailed hypothesis test used for?

Accepted Answer

Testing for an effect in a specific direction

Answer

Testing for any difference regardless of direction

Answer

Comparing more than two groups

Answer

Testing proportions only