Type I and II Errors (classic)

Which of the following statements is true about risking a Type II error? A. We risk it when we fail to reject the null hypothesis. B. The same decision as to whether or not to reject a null hypothesis can risk a Type I and Type II error simultaneously. C. We risk it when we reject the null hypothesis. D. None of these.

A. We risk it when we fail to reject the null hypothesis.

Although the null hypothesis may be implausible, it is never impossible. A. true B. false

A. true

Every time we opt not to reject the null hypothesis, we inescapably risk making a Type II error. A. true B. false

A. true

The probability of committing a Type I error is the p value. A. true B. false

A. true

The most appropriate significance level in evidence-based practice research: A. Is determined by mathematical theory. B. Can vary, depending upon the sample size and judgments about the relative seriousness of Type I and Type II errors. C. Should always be .05. D. Should always be .10.

B. Can vary, depending upon the sample size and judgments about the relative seriousness of Type I and Type II errors.

Which of the following statements is/are correct about p-values and significance levels? A. If the p-value is .05, and the significance level is .04, then the result is statistically significant. B. If the p-value is .04, and the significance level is .05, then the result is statistically significant. C. If the p-value is .051, and the significance level is .05, then the result is statistically significant. D. All of these.

B. If the p-value is .04, and the significance level is .05, then the result is statistically significant.

An experiment with a small sample is conducted to test the effectiveness of a promising new intervention for treating substance abuse. The experimental group's outcome is better than the control group's outcome, but the results are not statistically significant. The implication of this finding for evidence-based practice is: A. The new intervention was effective, but not as effective as predicted. B. It is conceivable that the new intervention is effective, although we cannot rule out sampling error as the explanation for the research finding. Additional testing of this intervention with a larger sample size would be in order. C. The new intervention was ineffective. D. None of these.

B. It is conceivable that the new intervention is effective, although we cannot rule out sampling error as the explanation for the research finding. Additional testing of this intervention with a larger sample size would be in order.

We commit a Type I error when we: A. Reject a true research hypothesis. B. Reject a true null hypothesis. C. Fail to reject a false null hypothesis. D. Fail to reject a false research hypothesis.

B. Reject a true null hypothesis.

In evidence-based practice research, Type I errors are always more serious than Type II errors. A. true B. false

B. false

In evidence-based practice research, Type II errors are always more serious than Type I errors. A. true B. false

B. false