Hi All
I am using survey data so I ran ZIP using the
following commands
y = x1 x2 x3 x2*x3 [iweight=perwt00f ],inflate(x1 x2
x3 x2*x3) score(zip*)
suest ., svy
Now I want to test if x2 + x2*x3=0.
I used the following command
lincom x2 + x2*x3
But I get the following error message
matrix has missing values
r(504);
Am I missing something trivial here?
I also tried using the test command
test x2 = - x2*x3
Adjusted Wald test
( 1) [y]x2 + [y]x2*x3 = 0
F( 1, 156) = 8.24
Prob > F = 0.0047
Since I am using survey data I included nosvyadjust
too.
test x2 = - x2*x3, nosvyadjust
Unadjusted Wald test
( 1) [y]x2 + [y]x2*x3 = 0
F( 1, 156) = 8.24
Prob > F = 0.0047
Is the test command doing what lincom would have done?
Can I use the results from test command to test if x2
+ x2*x3=0?
I would really appreciate if some can help me with
this.
Thank you for your time.
Regards
Anju
____________________________________________________________
Anju Parthan,
Doctoral Candidate,
The University of Texas at Austin, PHAR-PHARMACY ADMIN
1 UNIVERSITY STATION A 1930, AUSTIN, TX-78712
Tel: (512) 459-4942; Fax: (512) 471-8762
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