Hi all,
I am testing 24 compounds and accessing their mortality (%) under a pest. I am using the proc GENMOD with dist binomial and link logit. I would like to know if it is possible to make multiple comparisons, similar to Tukey in ANOVA, to compare these insecticides. Which PROC should I use? Thanks in advance.
Elizeu (beginner user)
You didn't say waht version of SAS you are using nor what your model looks like. That might make a difference.
Here is some sample data and code. Perhaps you can modify it for your needs:
data data1;
input Compound Success Trials Explanatory;
datalines;
1 20 30 10
2 10 18 8
3 15 30 5
4 20 55 5
5 5 60 3
11 20 28 9
12 11 16 8
13 14 25 6
14 18 45 4
15 7 54 2
;
proc genmod data= data1;
class Compound;
model Success/Trials = compound /link=logit dist=binomial;
lsmeans Compound / adjust=tukey pdiff plots=diff;
run;
I'm not an expert in multiple comparisons, but I think you can do this with the LSMEANS statement, which supports the ADJUST= option.
For more complicated comparisons, you can read about the LSMESTIMATE statement in Kiernan et al (2011) "CONTRAST and ESTIMATE Statements Made Easy: The LSMESTIMATE Statement " The paper contains many examples. Maybe you will find one that looks like your data.
Rick_SAS thank you so much. I will read this material.
"The option is not supported by the procedures that perform chi-square-based inference (GENMOD, LOGISTIC, PHREG, and SURVEYLOGISTIC)."
http://support.sas.com/documentation/cdl/en/statug/68162/HTML/default/viewer.htm#statug_intro
You didn't say waht version of SAS you are using nor what your model looks like. That might make a difference.
Here is some sample data and code. Perhaps you can modify it for your needs:
data data1;
input Compound Success Trials Explanatory;
datalines;
1 20 30 10
2 10 18 8
3 15 30 5
4 20 55 5
5 5 60 3
11 20 28 9
12 11 16 8
13 14 25 6
14 18 45 4
15 7 54 2
;
proc genmod data= data1;
class Compound;
model Success/Trials = compound /link=logit dist=binomial;
lsmeans Compound / adjust=tukey pdiff plots=diff;
run;
A search of the doc revelas that the phrase "The option is not supported by..." appears in the ADJDFE= option. Don't use that option. Use ADJUST=TUKEY (or whatever other method you want).
That is right. My mistake. Thank you for your patience!
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