Erratum-Page 286

Here is the first of what we hope will prove to be a very short list of errata.

Shawn Powell of Casper College wrote:

"I have a question on a formula and significance test results shown on page 286. What was the df for MS residual and the number of levels of the IV used to arrive at the probability figures near the bottom of the page. Using the charts provided on pages 449 and 450 (which by the way are shown as "-" in the text on page 286) I used a df of 18 and an IV level of 2 and arrived at .05 = 2.97 and .01 = 4.07. If this is correct then the values to the right of the formula don't match up with the results shown."

Chris Spatz responded:

"To determine correct HSD critical values, the number of levels of the IV is the number in the original ANOVA problem rather than the number in the HSD test. Thus, for the HSD tests on page 286, the number is 3 and not the 2 in the HSD test. I'm afraid that our last paragraph on the page really needs some improving. Our only clue to you to use 3 is the word ANOVA. Upon re-reading, it is clear that the insertion of the numbers needed for the critical values (df = 18 and number of levels = 3) would improve the communication of what we actually did."

In addition, there is a typographical error in the last paragraph of page 286. The first two sentences should read:

"To interpret HSD values, use Table C.5 in appendix C. Critical values for alpha = .05 are on page 449 (missing page number in original); those for alpha = .01 are on page 450 (missing page number in the original)."

Our thanks to Dr. Powell and his sharp eyes. If anyone else spots similar issues please contact us.