topic Re: GLM vs TTEST [how to improve your question] in SAS Programming

GLM vs TTEST

ralphbenno — Sat, 30 Mar 2019 20:26:24 GMT

I am having a bit trouble of deciding between PROC TTEST and PROC GLM

I m testing the rate between 2 variable over a group of years.

Is either one OK?

Quest 2. now I have 5 group of years. I want to test the rates of the variables for each group of years if some group years I have matching set. How to do the second part.

help?

Re: GLM vs TTEST [how to improve your question]

Community_Guide — Sat, 30 Mar 2019 21:51:42 GMT

Hello @ralphbenno,

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Re: GLM vs TTEST

ralphbenno — Sat, 30 Mar 2019 22:47:09 GMT

I am testing 750 data points

the column are in year, age sex the rows are group of year 1900-1910...ect it goes all the way up to 1990-2000

the data is mortality rate

I wanted to test the mean between female and male from yer 1900 till 2000

I wanted to know if mortality for female are higher than male,

should I use proc glm or proc ttest. in the example below

proc glm data = Project;
class sex;
where sex in ("f" "m");
model rate = sex;
run;
quit;

proc ttest data = Project;
class sex;
var rate;
where sex in ("f" "m");
run;
quit;

then 2nd test

there are 10 years grouping and each years there are 100 mortality rate points. I would like to do a pairing comparison for each 10 years. to determine if there was a significant changes.

I am not sure about the code . it could look like that

I should have 10 groups and tukey test will tell me if there is a significant between years group

I cannot set it up correctly. I attached my sas code

proc glm data=project;
class sex;
where sex in ("t");
model rate = year sex / solution;
means year sex/ tukey;
run;
quit;

ok see if you can help

Re: GLM vs TTEST

PaigeMiller — Sun, 31 Mar 2019 11:23:21 GMT

Under the right conditions, GLM and TTEST ought to give equivalent answers. GLM will result in a F test, TTEST will result in a t-test, however if the GLM F-test is statistically significant, then the t-test will also be statistically significant, and vice versa.

then 2nd test

there are 10 years grouping and each years there are 100 mortality rate points.

I would like to do a pairing comparison for each 10 years.

I don't know what "pairing comparison" means. Show us with a small data set, and explain what you want to do in more detail.