Review: Exam 2a

A p-value below 0.05 is considered statistically significant in most scientific studies.

• True

• False

Answer explanation

A p-value below 0.05 is commonly used as a threshold for statistical significance, though this is arbitrary and can vary depending on the field or context.

A t-test is suitable for comparing more than two groups.

• True

• False

Answer explanation

A t-test is designed to compare the means of two groups. For more than two groups, an ANOVA (analysis of variance) is more appropriate.

If the p-value in a one-way ANOVA is less than 0.05, you fail to reject the null hypothesis.

• True

• False

Answer explanation

If the p-value in a one-way ANOVA is less than 0.05, you reject the null hypothesis. A p-value below 0.05 suggests there is statistically significant evidence to conclude that at least one group mean is different from the others.

Repeated measures ANOVA generally has more statistical power because it controls for individual differences, which reduces the error variance.

• True

• False

Answer explanation

Repeated measures ANOVA generally has more statistical power because it controls for individual differences, which reduces the error variance.

A company compares the sales performance of two different sales strategies using an independent t-test. The test yields a p-value of .048.

What does the company conclude?

• Reject the null hypothesis.

• Fail to reject the null hypothesis.

A study assesses the effectiveness of a new training program by measuring employee performance before and after the program using paired t-test. The test yields a p-value of .065.

What does the study conclude?

• Reject the null hypothesis.

• Fail to reject the null hypothesis.

A marketing team analyzes customer satisfaction ratings across four different advertising campaigns using an ANOVA. The test yields a p-value of .005.

What does the team conclude?

• Reject the null hypothesis.

• Fail to reject the null hypothesis.

A researcher tests the effect of three different diets on weight loss among participants using an one-way ANOVA. The test yields a p-value of .120.

What does the researcher conclude?

• Reject the null hypothesis.

• Fail to reject the null hypothesis.

A teacher wants to compare the effectiveness of three study methods on students' test scores. She randomly assigns 30 students to one of the three methods: Flashcards, Group Study, and Online Quizzes.

Which statistical test should the teacher use?

• Independent t-Test

• Dependent t-Test

• One-Way ANOVA

• Repeated-Measure ANOVA

A researcher wants to examine how different sleep quality levels affect reaction time. She tests the same group of 20 participants under three conditions: poor sleep, moderate sleep, and good sleep.

Which statistical test should the researcher use?

• Independent t-Test

• Dependent t-Test

• One-Way ANOVA

• Repeated-Measure ANOVA