RE: Sample size question
G*Power is a powere analysis package that is freely available. You can download it at: http://www.psychologie.uni-trier.de:8000/projects/gpower.html You can calculate a sample size for a given effect size, alpha level, and power value. -Original Message- From: Scheltema, Karen [mailto:[EMAIL PROTECTED]] Sent: Friday, February 23, 2001 10:07 AM To: [EMAIL PROTECTED] Subject: Sample size question Can anyone point me to software for estimating ANCOVA or regression sample sizes based on effect size? Karen Scheltema Statistician HealthEast Research and Education 1700 University Ave W St. Paul, MN 55104 (651) 232-5212 fax (651) 641-0683 [EMAIL PROTECTED] = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ = = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
RE: Sample size question
Thanks! This was exactly what I was looking for! Karen Scheltema Statistician HealthEast Research and Education 1700 University Ave W St. Paul, MN 55104 (651) 232-5212 fax (651) 641-0683 [EMAIL PROTECTED] > -Original Message- > From: Magill, Brett [SMTP:[EMAIL PROTECTED]] > Sent: Friday, February 23, 2001 9:53 AM > To: 'Scheltema, Karen'; [EMAIL PROTECTED] > Subject: RE: Sample size question > > G*Power is a powere analysis package that is freely available. You can > download it at: > > http://www.psychologie.uni-trier.de:8000/projects/gpower.html > > You can calculate a sample size for a given effect size, alpha level, and > power value. > > > -Original Message- > From: Scheltema, Karen [mailto:[EMAIL PROTECTED]] > Sent: Friday, February 23, 2001 10:07 AM > To: [EMAIL PROTECTED] > Subject: Sample size question > > > Can anyone point me to software for estimating ANCOVA or regression sample > sizes based on effect size? > > Karen Scheltema > Statistician > HealthEast > Research and Education > 1700 University Ave W > St. Paul, MN 55104 > (651) 232-5212 fax (651) 641-0683 > [EMAIL PROTECTED] > > > > = > Instructions for joining and leaving this list and remarks about > the problem of INAPPROPRIATE MESSAGES are available at > http://jse.stat.ncsu.edu/ > = = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: Sample size question
You can use Sample Power from SPSS (a.k.a. Power and Preceision) or PASS 2000 from NCSS. For more info, please visit: http://www.spss.com http://www.ncss.com http://seamonkey.ed.asu.edu/~alex/teaching/WBI/power_es.html --- --"Regression to the mean" is not always true. After 30, my weight never regresses to the mean. Chong-ho (Alex) Yu, Ph.D., MCSE, CNE Academic Research Professional/Manager Educational Data Communication, Assessment, Research and Evaluation Farmer 418 Arizona State University Tempe AZ 85287-0611 Email: [EMAIL PROTECTED] URL:http://seamonkey.ed.asu.edu/~alex/ = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: Sample size question
"Scheltema, Karen" wrote: > Can anyone point me to software for estimating ANCOVA or regression sample > sizes based on effect size? Look here: http://www.interchg.ubc.ca/steiger/r2.htm Chuck -<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>- Chuck Cleland Institute for the Study of Child Development UMDNJ--Robert Wood Johnson Medical School 97 Paterson Street New Brunswick, NJ 08903 phone: (732) 235-7699 fax: (732) 235-6189 http://www2.umdnj.edu/iscdweb/ http://members.nbci.com/cmcleland/ -<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>- = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
RE: Sample size question
I tried the site but received errors trying to download it. It couldn't find the FTP site. Has anyone else been able to access it? Karen Scheltema Statistician HealthEast Research and Education 1700 University Ave W St. Paul, MN 55104 (651) 232-5212 fax (651) 641-0683 [EMAIL PROTECTED] > -Original Message- > From: Chuck Cleland [SMTP:[EMAIL PROTECTED]] > Sent: Friday, February 23, 2001 11:04 AM > To: [EMAIL PROTECTED] > Subject: Re: Sample size question > > "Scheltema, Karen" wrote: > > Can anyone point me to software for estimating ANCOVA or regression > sample > > sizes based on effect size? > > Look here: > > http://www.interchg.ubc.ca/steiger/r2.htm > > Chuck > > -<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>- > Chuck Cleland > Institute for the Study of Child Development > UMDNJ--Robert Wood Johnson Medical School > 97 Paterson Street > New Brunswick, NJ 08903 > phone: (732) 235-7699 >fax: (732) 235-6189 > http://www2.umdnj.edu/iscdweb/ > http://members.nbci.com/cmcleland/ > -<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>-<>- > > > = > Instructions for joining and leaving this list and remarks about > the problem of INAPPROPRIATE MESSAGES are available at > http://jse.stat.ncsu.edu/ > = = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
RE: Sample size question
>I tried the site but received errors trying to download it. It couldn't >find the FTP site. Has anyone else been able to access it? > >Karen Scheltema >Statistician >HealthEast >Research and Education >1700 University Ave W >St. Paul, MN 55104 >(651) 232-5212 fax (651) 641-0683 >[EMAIL PROTECTED] > >> -Original Message- >> From:Chuck Cleland [SMTP:[EMAIL PROTECTED]] >> Sent:Friday, February 23, 2001 11:04 AM >> To: [EMAIL PROTECTED] >> Subject: Re: Sample size question >> >> "Scheltema, Karen" wrote: >> > Can anyone point me to software for estimating ANCOVA or regression >> sample >> > sizes based on effect size? >> >> Look here: >> >> http://www.interchg.ubc.ca/steiger/r2.htm >> >> Chuck > Karen, I just looked, and was able to access the site and download the files. Dan Nordlund = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: Sample size question
On 23 Feb 2001 12:08:45 -0800, [EMAIL PROTECTED] (Scheltema, Karen) wrote: > I tried the site but received errors trying to download it. It couldn't > find the FTP site. Has anyone else been able to access it? As of a few minutes ago, it downloaded fine for me, when I clicked on it with Internet Explorer. The .zip file expanded okay. I used right-click (I just learned that last week) in order to download the .pfd version of the help. [ ... ] < Earlier Q and Answer > "Can anyone point me to software for estimating ANCOVA or regression sample sizes based on effect size?" > > Look here: > > http://www.interchg.ubc.ca/steiger/r2.htm Hmm. Placing limits on R^2. I have't read the accompanying documentation. On the general principal that you can't compute power if you don't know what power you are looking for, I suggest reading the relevant chapters in Jacob Cohen's book (1988+ edition). -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =