just echoing what everyone else has said. My roommate wasnt able to do a single pullup, so he started with a chair too. Now (start of week 7) he can do about 3-4 pullups a set, then he busts out an extra 10 with a chair. I have gone from 3-4 pullups to start to 10-12 a set.

Chair pullups can be extremely effective if you use as little leg support as possible. Also, try and come down from the pullup a little slower than usual, this will give you some more muscle tension and make your movements more productive.

No matter what level you are, doing ANYTHING=improvements over time. so stick with it!

Thanks for the advice everyone!