Msg#: 3500781 posted 7:26 pm on Nov 9, 2007 (gmt 0)
"if a low Campaign CTR affects Quality Score" : CTR may not affect your Quality Score in direct way but it will affect your overall ranking or the CPC that you pay for each click. The best way to run content campaigns is to separate it from the "Search" campaigns. You will have to manage 2 campaigns but it will give you more control over all the metrics.
Msg#: 3500781 posted 5:11 am on Nov 10, 2007 (gmt 0)
Google doesn't penalize you for running search and content in the same campaign. They account for the fact that content CTR sucks compared to search. The little question mark next to content CTRs even says so.
As for it's effect on QS, there are two quality scores: one that determines your ad rank (where you show up in the sponsored results, and for your landing page quality. The landing page quality score determines how much you need to 'pay to play' for minimum bids, and a whole bunch of other stuff. I'm not aware of CTR affecting landing page QS, but who knows these days....