Currently we have the following regression tags: regression, linear-regression, logistic-regression, nonlinear-regression, stepwise-regression, ridge-regression, dynamic-regression, meta-regression. This is perfectly normal, since there are a lot of questions related to the regression and separate tags makes a lot of sense.
I would like to propose however to remove multiple-regression tag, since usually all the regressions are multiple.
I also propose standard formulation for all the specific regression tag wikis:
[Insert regression type] regression is a type of regression, where [insert some characterisation of the particular regression type]
The example for linear regression would be:
Linear regression is a type of regression, where regression function is linear. This is the most widely used regression type.
I've already edited linear, logistic and dynamic regression tag wiki's, the edits will appear when they are approved.
Update I see that linear regression tag was merged with regression tag. This seems a good thing. It would be also good to merge the multiple-regression tag with regression (by merging I mean making synonym or something to that effect). I looked at the questions tagged with this tag, they all mention linear regression.