Chapter 15 Multiple choice questions

. Assuming a starting alpha level of 0.05, what is the alpha level if we Bonferroni correct for 18 tests?

. What does a p-value of 0.026 change to after Bonferroni correction for 4 comparisons?

. How many of the following p-values remain significant after applying Holm-Bonferroni correction (assuming alpha = 0.05)?
0.03, 0.01, 0.9, 0.6, 0.002, 0.045

. Apply false discovery rate correction to the p-values from Question 3. How many remain significant?

. What is the familywise error rate for 8 comparisons with an alpha level of 0.01?

. Download the data file for the multiple-choice questions for Chapter 15 , and open it in R. The file contains a matrix called timesignal, which consists of data from 25 participants (rows) at 100 time points (columns). First conduct a t-test comparing to 0 at each time point. How many are significant?

. Use the code on pages 235-6 to find all of the contiguously significant clusters, assuming a cluster forming threshold alpha of 0.05. How many clusters are there (before cluster correction)?

. What is the summed t-value of the largest cluster?

. Generate a null distribution based on resampling the largest cluster. Approximately, what are the upper and lower 95% confidence intervals of the distribution?

. How many clusters remain significant following cluster correction?

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