You are performing the Wilcoxon rank-sum test. The 10^th through 12^th values in an ordered array of pooled sample data all equal $100, while the 9^th value is less than $100 and the 13^th value is more than $100. The appropriate ranks for the three $100 values are: A) 9, 9, 9 B) 10, 10, 10 C) 11, 11, 11 D) 12, 12, 12 E) 13, 13, 13

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In the Wilcoxon rank-sum test, when there are ties (identical values), the ranks assigned to these values are the average of the ranks that would have been assigned if the values were slightly different. Since the three $100 values are the 10th, 11th, and 12th in the ordered array, their ranks should be averaged: (10+11+12)/3 = 11. Therefore, each of the three $100 values should be assigned the rank of 11.

You Are Performing the Wilcoxon Rank-Sum Test