Re: sample size determination

[Zdaniuk, Bozena]

Sara, there are websites which calculate sample sizes for different
types of analyses. One that I use is:
http://www.stat.uiowa.edu/~rlenth/Power/index.html

once you go to the window you want, click on Help if you need additional
explanation of the calculators.
Bozena

Bozena Zdaniuk, Ph.D.

University of Pittsburgh

UCSUR, 6th Fl.

121 University Place

Pittsburgh, PA 15260

Ph.: 412-624-5736

Fax: [phone]

email: [hidden email]


-----Original Message-----
From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf Of
Sara Cadden
Sent: Friday, March 30, 2007 12:09 PM
To: [hidden email]
Subject: sample size determination

I will be testing 5 different promotional pieces in 3 markets. 40,000
units
of each piece will be tested in each of the three markets, for a total
of
600,000 promotional pieces. Average redemption rate today is
approximately
2%. So, the proposed sample size for each cell will be 800. Under the
assumption of 95% CI, would it be feasible to reduce sample size? I
would
like to reduce the cost of this test, if possible. Analysis of Variance
will
be used to determine significance of the new promotional pieces on
various
target markets.

Thank you!

[Jim Moffitt]

Sarah:
I've never used them, so I cannot vouch for them, but check out this
consultancy. They may be able to help.
http://www.lucidview.com/

-----Original Message-----
From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf Of
Sara Cadden
Sent: Friday, March 30, 2007 11:09 AM
To: [hidden email]
Subject: sample size determination

I will be testing 5 different promotional pieces in 3 markets. 40,000
units of each piece will be tested in each of the three markets, for a
total of 600,000 promotional pieces. Average redemption rate today is
approximately 2%. So, the proposed sample size for each cell will be
800. Under the assumption of 95% CI, would it be feasible to reduce
sample size? I would like to reduce the cost of this test, if possible.
Analysis of Variance will be used to determine significance of the new
promotional pieces on various target markets.

Thank you!