The probability of a type II error for the t test for can be computed in the same manner as it was computed for the t tests of Chapter 8.

If the alternative value of b1 is denoted by , the value of is first calculated, then the appropriate set of curves in Appendix Table A.17 is entered on the horizontal axis at the value of

d, and b is read from the curve for df. An article in the Journal of Public Health Engineering reports the results of a regression analysis based on observations in which and efficiency of BOD removal. Calculated quantities include

, and .

Consider testing at level .01 , which states that the expected increase in % BOD removal is 1 when filter application temperature increases by 1°C, against the alternative

. Determine P(type II error) when br . Ha: b1 . 1 1 5 2, s 5 4 H0: b1 5 1 bˆ gxi 5 402, gxi 1 5 1.7035 2 5 11,098, s 5 3.725 x 5 filter application temperature (8C) y 5 %

n 5 15 n 2 2 d 5 u b10 2 br 1 u s

B n 2 1