i now have a macro that will do power/beta calculations in the 1 sample z test case ... that runs in MINITAB and produces nice overlapping graphs for the moment, the power/beta macro is done ... but, subject to improvements later ... especially if any of you have a good suggestion that i can implement currently, you enter the null mean value, alternative mean value, population standard deviation, and the sample size n ... and it then runs and produces the overlapping normal distributions with power and beta calculated ... at the moment ... the default is a 2 tailed alpha of .05 ... i will change this to allow more options later the nice thing about the macro is that one can run it under one set of conditions ... say, null = 100, alternative = 102, population sd = 16, and n=25 ... get the output graphs ... then, run it again using n=100 ... and see the impact changing sample size has on power and beta ... the link is http://roberts.ed.psu.edu/users/droberts/powbeta.htm at the moment, you have to cut and paste the macro ... save it on your system and give it whatever name you want ... i have used powbeta.MAC ... it is a file that you run at the prompt MTB> %powbeta you might want to copy to your (if you have minitab) MACROS folder in the minitab directory any comments are welcome _________________________________________________________ dennis roberts, educational psychology, penn state university 208 cedar, AC 8148632401, mailto:[EMAIL PROTECTED] http://roberts.ed.psu.edu/users/droberts/drober~1.htm ================================================================= Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =================================================================
