Six Second-Graders Tried Tossing a Ball into a Basket Ten

Multiple Choice

Six second-graders tried tossing a ball into a basket ten times each. Their teacher then suggested a different way of tossing the ball, and the six students tried again. The number of successful tosses, before and after the teacher's suggestion, are shown below. Find the sum of the positive and negative rank sums as in a Wilcoxon signed-rank test.

A) positive rank sum = 2; negative rank sum = -1
B) positive rank sum = 4; negative rank sum = -2
C) positive rank sum = 6; negative rank sum = -2
D) positive rank sum = 7; negative rank sum = -3