Question

16.          Briefly discuss: What information do you look at to evaluate whether an effect obtained in an experiment is large enough to have “practical” or “clinical” significance?

19.          A p value can be interpreted as a (conditional) risk that a decision to reject H0 is a Type I error, but the p values reported in research papers are valid indications of the true risk of Type I error only if the data meet the assumptions for the test and the researcher has followed the rules that govern the use of significance tests. Identify one of the most common researcher behaviors that make the actual risk of Type I error much higher than the “nominal” risk of Type I error that is set by choosing an alpha level.

Consider the following small set of scores. Each number represents the number of siblings reported by each of the N = 6 persons in the sample: X scores are

[0, 1, 1, 1, 2, 7].

e.    Compute the sample variance, s2, for this set of six scores.

Answer 1

To evaluate whether an effect obtained in an experiment is large enough to have “practical” or “clinical” significance, we use the p-value of the test. If the p-value of the test is less than the type I error, then we reject the null hypothesis of the test otherwise we fail to reject the null hypothesis.

The most common researcher behaviors that make the actual risk of Type I error much higher than the “nominal” risk of Type I error that is set by choosing an alpha level is the violation of the assumptions of the test.

Please give a Thumps Up if you like the solution.

Best wishes.