Six Sigma Green Belt Certification Practice Exam

Which statement is true about the null hypothesis?

1. The assumption with the null hypothesis is that the variation is non-random

2. The null hypothesis can be rejected or failed to be rejected

3. It can be accepted if the evidence does not support rejecting it

4. The null hypothesis asserts that something important is occurring

The correct answer is: The null hypothesis can be rejected or failed to be rejected

The statement that the null hypothesis can be rejected or failed to be rejected is accurate because it reflects the fundamental nature of hypothesis testing in statistics. The null hypothesis serves as a starting point for statistical tests and is generally framed in a way that indicates no effect or no difference. As such, the outcomes of hypothesis testing revolve around whether there is enough statistical evidence to reject this null hypothesis in favor of an alternative hypothesis. In conducting hypothesis tests, researchers gather data and assess whether the observed results deviate significantly from what the null hypothesis would predict. If the evidence against the null hypothesis is strong enough, it can be rejected. Conversely, if the evidence is insufficient, the null hypothesis is not rejected, indicating a failure to find significant evidence against it. This understanding is crucial in the context of Six Sigma and quality improvement initiatives, as it allows practitioners to make informed decisions based on data analysis and statistical evidence.