The Statistical Models

Loglinear Models

What model is the following SAS program investigating? What question is this part of the program stress.sas asking?

Probably more interesting is to see the effects of both gender and age on stress (later in the same program) ...

In the third type of model where you treat both stress and smoing as responses what happens? Does the problem get more complex? How so?

Polytomous Logisitic Regression Models

Why is this an example of a polytomous logisitic regression?

Could a loglinear model analysis apporach be taken with this data? What are the consequences of this type of an approach with this type of experiment? What happens?

A loglinear approach can be taken for a couple of reasons: (a) to identify possible associations among variables to assist in finding appropriate polytomous models and (b) to illustrate differences between treating variables as responses and factors.

Sample SAS programs (2 responses and 4 responses)

(Again, see the SAS program stress.sas.)

Polytomous Logistic Regression Models with One Response

• Stress on Gender (simplest polytomous model)
• Stress on Smoking, Age, and Gender
• Smoking on Gender
• Smoking on Stress, Age, and Gender

Polytomous Logistic Regression Models with Two Responses

• Stress and Smoking on Gender
• Stress and Smoking on Age
• Stress and Smoking on Gender and Age