I am having trouble finding any resources to help me interpret my logistic regression results. I'm using SPSS, but I don't think that matters a whole lot. I understand the odds ratio concept (as well as a beginner can), but the real confusion for me is in determining significance of independent categorical variables with more than two categories. Nearly all examples I find have theirs coded as 0 or 1. With my independent variables, I have as many as 17 categories for one variable.
Specifically, here is an example:
For the "crash type" variable as a whole, the significance is .027 (significant)
Then there are 18 categories for "crash type," none of which individually show significance in the model.
How do I interpret this or report this? Would it be to say that crash type is a significant factor, but no specific type is? That doesn't exactly sound logical, does it? And vice versa... for a categorical variable which is significance "overall," but an individual category is... how to go about this?