Controlling for time


Thank-you for taking the time to read this post. I have managed to get myself very confused about what is (hopefully) quite a simple problem.

I am aiming to look at the engagement on Twitter during election debates. I have collected tweets and have coded them in regards to their policy areas. I want to see whether Twitter users have a good understanding of devolved and non-devolved policy. Therefore, my DV is whether or not a particular policy area is mentioned (e.g. health mentioned/ not mentioned), and my IV is whether it is a general or local debate.

However, in order to get an accurate reading of the Twitter users understandings I need to control for the length of time the politicians spent discussing each policy area as this could bias the results (i.e. its not that they understand its a devolved area- they just are tweeting about it because the are talking about it on telly).

I have the amount of minutes each policy area was discussed, but I am unsure where to put this in the model. I have tried to create a 'time' variable which gives each tweet the time the politicians spent discussing it during the debates- but this is throwing up strange results in a logistic regression.

Any ideas of how to do this would be really beneficial! Thank-you very much!