Problem Set #9 Statistics

Is it more meaningful to find a significant difference with a relatively small sample size or with a relatively large sample size? a) It points to a more robust difference if you have a small sample size b) It points to a more substantial difference if you have a large sample size c) The two differences are equally substantial d) We can't tell anything about the size of the effect from what is given here

a) It points to a more robust difference if you have a small sample size

When we have two independent samples, a confidence limit is generally used to a) say something about the difference between population means b) say something about the difference between sample means c) specify the location of a single sample mean d) refine the estimate of the variance

a) say something about the difference between population means

If we use the standard approach to solve for the necessary sample size so that we have power =.75 in an independent two-sample t test, the value of N that we will obtain is a) the number of subjects we will need in each group b) the number of subjects we will need overall c) the number of groups we will need to run d) the number of subjects that we actually have available

a) the number of subjects we will need in each group

Inn calculating power we calculate a statistic called delta. This statistic is a) the effect size b) the sample size c) a function of the effect size and the sample size d) the difference we are looing for

c) a function of the effect size and the sample size

Power is defined as the a) probability of rejecting a true null hypothesis b) probability of accepting a false null hypothesis c) probability of rejecting a false null hypothesis d) power is not related directly to the null hypothesis

c) probability of rejecting a false null hypothesis