RhinoFish - 3:28 pm on Jan 31, 2011 (gmt 0)
ctr = click thru rate.
it is, by far, the biggest factor in the quality score equation.
use only relevant keywords, more narrow match types, improved ads, more negative keywords -- all to focus you aim.
improve your ads via (1) better copy, (2) more thorough testing, and (3) better segmenting of your ad groups into smaller targets, making the ads more directly related to your target keywords (also referred to as... more granular account structure).
low QS and sky high prices are G's stick that's telling you the same thing i've said above... in shorthand it's...