Certified Six Sigma Black Belt Exam Certified Six Sigma Black Belt Hypothesis Testing Questions and Answers 3

Question 1

What effect does increasing the sample size have on the power of a hypothesis test, assuming all other factors remain constant?

Accepted Answer

Power increases

Answer

Power decreases

Answer

Power remains unchanged

Answer

Power becomes unpredictable

Question 2

A Black Belt uses a chi-square test of independence. What type of data is this test designed to analyze?

Accepted Answer

Categorical data in a contingency table

Answer

Continuous data from two groups

Answer

Time-series data with trends

Answer

Ordinal data with ranks

Question 3

Which non-parametric test is the appropriate alternative to the one-sample t-test when the normality assumption is violated?

Accepted Answer

Wilcoxon signed-rank test

Answer

Mann-Whitney U test

Answer

Kruskal-Wallis test

Answer

Friedman test

Question 4

What does the confidence level of 95% mean in the context of hypothesis testing?

Accepted Answer

If the study were repeated many times, 95% of the intervals would contain the true parameter

Answer

There is a 95% chance the null hypothesis is true

Answer

95% of the data falls within the confidence interval

Answer

The test has 95% power to detect a difference

Question 5

When should a Black Belt use a one-tailed test instead of a two-tailed test?

Accepted Answer

When there is a specific directional hypothesis supported by prior knowledge

Answer

When the sample size is very large

Answer

When the data is non-normal

Answer

When comparing more than two groups

Question 6

What is the null hypothesis in a one-way ANOVA test?

Accepted Answer

All group means are equal

Answer

All group variances are equal

Answer

At least one group mean differs from the others

Answer

The data follows a normal distribution