and the probability on the right side is calculated for ∆ = 0.

(ii) Determine the above confidence interval for ∆ when m = n = 6, the confidence coefficient is 20 21 , and the observations are x : .113, .212, .249,

.522, .709, .788, and y : .221, .433, .724, .913, .917, 1.58.

(iii) For the data of (ii) determine the confidence intervals based on Student’s t for the case that F is normal.

Hint: D(i) ≤ ∆ < D(i+1) if and only if U∆ = mn − i, where U∆ is the statistic U of