I am trying to understand what factors affect debate participation in parliament and how this has changed over time. I want to run a regression in R, with a count variable as the dependent variable (the number of times each member has participated in debate in a specific policy area per year) and 4 explanatory variables - sex of the member (dummy variable), political party of the member (dummy variables for 3 main parties), whether or not they hold a leadership position in their party (dummy variable) and the number of years since they were elected (categorical variable).
I want to run a regression analysis over 11 years (2000 - 2010) to understand if changes have taken place over time.
I haven't worked with regressions over periods of time before. I have another categorical variable for the years. I was going to do a negative binomial regression, but I am not sure how to analyse how the debate participation has changed over time. Can I just include my year variable as an explanatory variable? Or should I do a two step regression?