Statalist The Stata Listserver


[Date Prev][Date Next][Thread Prev][Thread Next][Date index][Thread index]

Re: st: statistical test to compare two survey means from two estimating equations


From   "Austin Nichols" <[email protected]>
To   [email protected]
Subject   Re: st: statistical test to compare two survey means from two estimating equations
Date   Mon, 4 Dec 2006 14:36:29 -0500

Brent Fulton --
I think the last option is the best:
svy: tab y Michigan_dummy, col se

(the col and se options are important), after which you can
gen p21=.
gen p22=.
mat li e(b)
test p21=p22

Note that the concept of the mean for Michigan being different from
the national mean should rightly be reframed as the the mean for
Michigan being different from the mean for the balance of the nation,
as this reductio ad absurdum will illustrate: think of a sample of 3
people and compare the mean of the balance of the nation to the
national mean (e.g. are all people not named Brent Fulton
significantly more likely to have high blood pressure than the average
American?).

Also note that if you have categorical data, you want to estimate
proportions, not means, and the fact that the mean of a dummy variable
is a proportion does not mean that statistical tests using -svy: mean-
or -svy: reg- are appropriate for categorical dependent variables.

On 12/4/06, Brent Fulton <[email protected]> wrote:
I'm using Stata 9.2 and my dataset includes a complex survey design with
pweights and strata IDs, which are states. I have individual-level
observations within each state and want to perform a simple statistical
test: does the national mean of variable y equal the state of e.g.,
Michigan's mean of y, where y is 0/1.

I've run the following and can examine if the e.g., 95% CI's overlap, but
would like to calculate the p-value that the means are equal.
.svy: mean y
.svy: mean y, subpop(Michigan_dummy)

Is there a post-estimation test that can compare the survey-based means
above?

I've also thought of the following, but both compare Michigan to
non-Michigan states (not the nation).
.svy: logit y Michigan_dummy
.svy: tab y Michigan_dummy


Thanks,
Brent


___________________________________
Brent D. Fulton, PhD
Health Services Researcher
Petris Center at UC Berkeley
Phone: 510-643-4102
Fax: 510-643-4281
Email: [email protected]
www.petris.org
*
*   For searches and help try:
*   http://www.stata.com/support/faqs/res/findit.html
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/



© Copyright 1996–2024 StataCorp LLC   |   Terms of use   |   Privacy   |   Contact us   |   What's new   |   Site index