SPSS - Logistic Regression - Continuous independent and moderating variables

[MarisaFernandes]

Hi,
I'm trying to analyse the relation between 4 independent variables and 1 dependant variable (yes=1, no=0), using Logistic Regression, in SPSS. Also, i'll add 5 moderating variables.

I have several doubts about that:

1) My independant variables are all continuous. I must group them into intervals, right? I read about Sturge's rule to do that. Is that a good option? Or do i have others?
2) My moderating variables are two categorical and three continuous. Since i'll test their moderating effect one by one, it is ok, right? And i must group the three continuous variables as well, am i right?

Hope you can help me. Thank you so much.
Marisa Fernandes

 

[CB]

1) My independant variables are all continuous. I must group them into intervals, right?

Nope, that would be unnecessary (and a bad idea).

 

[noetsi]

You never want to take an interval variable and turn it into a categorical one for lots of reasons....

 

[MarisaFernandes]

Oh God. I'm really a beginner.
But my independent variables are, for example, "average time to answer complaints", if I keep them as they are i'll have lots of possibilities... Won't it be a problem?

 

[CB]

Why do you think it would be problematic?

 

[MarisaFernandes]

Reading your question i realized how fool i was! I just have to show the relation between Independent variables and Dependent variable. THE RELATION. And for that it doesn't matter if i have a 7 items likert scale or a thousand items, right?

What about the moderating variables? I can use both categorical and continuous variables? Let's say i want to use "age" as moderator... in the relation between independent variables and dependant variables... would it be possible?

Thank U

 

[sabraznawaz]

Can any one show how to do this please? I mean logistic regression with moderators