Refer to the Applied Animal Behavior Science (June 2010) study of stress in cows prior to slaughter, Exercise 14.22. In the experiment, recall that the heart rate (beats per minute) of a cow was measured at four different pre-slaughter phases — (1) first phase of visual contact with pen mates, (2) initial isolation from pen mates for prepping, (3) restoration of visual contact with pen mates, and (4) first contact with human prior to slaughter. Thus, a randomized block design was employed. The simulated data for eight cows are reproduced in the accompanying table. Consider applying the nonparametric Friedman test to determine whether the heart rate distributions differ for cows in the four preslaughter phases. A MINITAB printout of the analysis follows.

a. Locate the rank sums on the printout.

b. Use the rank sums to calculate the F_r test statistic. Does the result agree with the value shown on the MINITAB printout?

c. Locate the p-value of the test on the printout. 

d. Provide the appropriate conclusion in the words of the problem if α = .05.

Data from Exercise 14.22

What is the level of stress (if any) that cows undergo prior to being slaughtered? To answer this question, researchers designed an experiment involving cows bred in Normandy, France. (Applied Animal Behavior Science, June 2010.) The heart rate (beats per minute) of a cow was measured at four different pre-slaughter phases—(1) first phase of visual contact with pen mates, (2) initial isolation from pen mates for prepping, (3) restoration of visual contact with pen mates,  and (4) first contact with human prior to slaughter. Data for eight cows (simulated from information provided in the article) are shown in the table. The researchers analyzed the data using an analysis of variance for a randomized block design. Their objective was to determine whether the mean heart rate of cows differed in the four pre-slaughter phases.

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COWSTRESS PHASE COw 2 3 4 124 124 109 107 100 98 98 99 3 103 98 100 106 4 94 91 98 95 122 109 114 115 6. 103 92 100 106 7 98 80 99 103 8 120 84 107 110 88 1, 1. 2.