Hi, Can someone help me with the Power calculation in Wonnolin BE module? According the help menu, Power = 1-(p1-p2) p1 = p-value associated with t1, where t1 = t (1-alpha/2),df – 0.2×RefLSM / DiffSE p2 = p-value associated with t2, where t2 = – t (1-alpha/2),df – 0.2×RefLSM / DiffSE I tried doing this by hand (just curious) I couldn’t get the correct value for power as shown in my winnonlin output: Values from my Winnonlin output: RefLSM = 3.0066809 Diff_SE = 0.047726099 df=62 alpha=0.95 Winnonlin gave a value of 0.99808478 for power. Thanks John
The Power value is accurate to only about four decimal places, due to limited accuracy of the t-inverse routine. Is that as close as you are getting?