So, Panda is likely not due to lack of content or excess of ads. That really only leaves duplicate content issues.
Duplicate content is copying content from another site, and let's face it, this is unfair and should be cracked down on. And from Google's perspective they want a mixture of content in their serps, not the same content from 10 different sites.
You all know if you have copied content from other sites or not. If you haven't corrected that yet, then you are not going to have any chance of being unpandalized.
Sure, there is the whole social popularity and user-behavior factors, but I personally don't buy into these - at least not as a Panda factor.