The best description of a type II error is that it occurs when: ...

[sam.t96]

The best description of a type II error is that it occurs when:
 
  A) The null hypothesis is rejected when it is true.
  B) One rejects the alternative hypothesis when it is false.
  C) The null hypothesis is accepted when it is false.
  D) One accepts the alternative hypothesis when it is true.

Question 2

Which ensures that a study's results are not due to chance alone?
 
  A) Rejecting the null hypothesis
  B) Setting the p value to .05
  C) Calculating the risk ratio
  D) Using a preventive study design

[kjohnson]

Answer to Question 1

Ans: C
Feedback:
A type II error occurs when one accepts the null hypothesis when it is false. A type I error occurs when the null hypothesis is rejected when it is true.

Answer to Question 2

Ans: B
Feedback:
The researcher should set the expected statistical p value, generally at .05, to ensure that the study results are not due to chance alone. Rejecting the null hypothesis when it is true is known as a type I error and does not ensure that a study's results are not due to chance alone. Relative risk is a ratio ranging from 0 to infinity that indicates the strength of the association between the risk factor and the outcome. However, calculating it does not ensure that a study's results are not due to chance alone. Using a preventive study design does not ensure that a study's results are not due to chance alone.