Wikipedia:Reference desk/Archives/Mathematics/2014 July 1

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July 1[edit]

What are these percents[edit]

I'm reading a message and it contains the following:

"Power to detect standardized effect is:

0.43 : 47% power to detect difference if 38 are in control and 38 have SE

0.86 : 96% power to detect difference if 38 are in control and 38 have SE

There is an 80% power to detect a standard difference of 0.64"

I understand how the values of 0.43 and 0.86 are calculated, using power calculations. It appears that there is a lookup table or something similar that converts 0.43 to 47%. However, I do not know of such a table. Does it make sense to anyone here? — Preceding unsigned comment added by 209.149.113.71 (talk) 12:50, 1 July 2014 (UTC)[reply]

This isn't a math problem, so you might do better at the Science Desk or perhaps the Computer Desk, which also deals with electronics. StuRat (talk) 15:23, 1 July 2014 (UTC)[reply]
After a lot of trial and error. This is a calculation of the probability to reject the null hypothesis. It left out the means used in the calculation, but if I use means from a previous message, I can calculate 0.43 for 47% and 0.86 for 96%. — Preceding unsigned comment added by 209.149.113.71 (talk) 16:59, 1 July 2014 (UTC)[reply]
Yes, it's Statistical power not Power-on self-test, Stu. Sorry I didn't have time to check this yesterday. Dbfirs 17:22, 2 July 2014 (UTC)[reply]
OK, thanks for the clarification. StuRat (talk) 04:12, 7 July 2014 (UTC)[reply]