Google announced they are working on technology that could soon allow vehicles to drive themselves. Just speak your destination and the car will take you there, safely, at its own pace. Little have they informed AdWords advertisers, though, but it turns out they have been using 'autopilot' technology to run their Quality Score calculations for years. No advertiser involvement needed nor desired.
The equation which governs the placement of ads in search results is so straightforward it's surprising how easy it is to misinterpret. Each time a search occurs, for each ad considered eligible, the advertiser's bid is multiplied by their Quality Score (which is determined largely by the ad's clickthrough rate) to get a quantity called the 'AdRank':
The ad with the highest AdRank gets placed at the top of the pile and the rest in descending order down the page. To get an AdRank that's say 10% higher, the bid must increase by 10%, the Quality Score by 10%, or some combination of the two. Higher bids cost more money though, so there are plenty of search marketers who advocate 'focusing' on improving your Quality Score. Unfortunately, these people are largely wasting their time, and yours.
The deceptive thing about Quality Score is that it looks like it is central to the AdRank equation (Actually, it is
of central importance, but to Google, not to the advertiser). As a corporation, Google serves three masters. One is the users of their search engine. Google wants to listen to them to make certain they are being shown good-quality natural results and good-quality ads. Almost by definition, a listing or ad that gets clicked on often (and with a low bounce rate) is a good result. In this way, the Quality Score acts like the 'Voice of the Searcher
However, Google must also listen to the advertisers, who are responsible for more than 95% of Google's revenue. If an advertiser offers a high bid for a keyword, that is a signal that that advertiser wishes for their ad to be placed highly for that term. So the bid acts like the 'Voice of the Advertiser
Let the implication of that sink in: It is in Google's best interest to ensure that the actions advertisers take have as little impact as possible on the Quality Score
. If advertisers controlled their own Quality Score, then they would control both pieces
of the AdRank equation, not just one, and the searchers' voice would be diminished accordingly. Just as the car of the future won't need you to wiggle the steering wheel, AdRank doesn't need the advertiser fiddling with the Quality Score. Only by ensuring that advertisers have little influence on their Quality Score can Google serve their third master best, their quarterly profit report.
How does Google find the Quality Score? One of Google’s AdWords help pages 
says that some of the important factors include:
- The keyword’s historical clickthrough rate (CTR)
- The account’s history, measured by the CTR of all ads in the account
- The historical CTR of the display URLs
- Your account's performance in the geographical region where the ad will be shown
OK, that’s just 4 different ways of saying ‘clickthrough rate’. Increasing your clickthrough rate will improve your Quality Score, but more clicks will hurt your profit if those clicks don’t convert. So simply attracting more clicks with enticing ad text in an effort to drive up your QS is not helpful. Quality Score doesn’t shine your shoes. Profit does.
Similarly, when calculating your Quality Score, Google compares your performance to other ads that have appeared in the same position
. So, simply bidding higher to get a higher CTR (and therefore, a better QS) won’t help either. One implication of the AdRank equation is that it would be counterproductive for Google to have your Quality Score be affected by your bid (or anything else the advertiser does), so conversely it stands to reason, your bid should not depend in any way on your Quality Score
Even if an advertiser can't affect their own Quality Score much and their bid shouldn't be affected by their QS, isn't there anything an advertiser can do improve their results? Some have suggested that adding ‘negative’ terms (to prevent your ad from showing in cases where that term appears in the search query) will help your QS. Wordstream says this 
: "Setting negative keywords in your PPC campaigns helps increase click-through-rate and Quality Score by reducing irrelevant impressions and clicks!" [UPDATE:
Sometime after this post was published, Wordstream changed their site to say "Setting negative keywords in your PPC campaigns helps reduce wasteful ad spend and boost ROI by killing irrelevant impressions and clicks!"]
Except, Google only uses information from cases where the search query was identical to the keyword when calculating your Quality Score. So, no, adding negative terms will not affect your QS in any way. (It might filter out non-converting traffic, so it can be worthwhile to do, but not because of a presumed effect on Quality Score.)
That's right - a default page is sufficient. According to Google, if your web server has a pulse, your landing page quality is high enough. When you think about it, that makes sense. Google doesn’t need to check the “quality” of each landing page, because searchers will do that for them. If searchers click an ad, and then quickly come back to Google’s SERP (i.e.
One other recommendation that many marketers make is for you to ensure that the keywords in your adgroups are closely related to each other and to the ad’s text. This is one of the few common recommendations regarding Quality Score that make sense. In the rules of their Online Marketing Challenge 
, a competition for marketing students, Google states that participating teams will be partly evaluated by an automated algorithm that examines the structure of the ad campaigns they set up. If Google is using this system to evaluate student teams for an advertising competition, then they are probably using it for real advertisers too. However, Google probably uses this metric as a ‘bozo filter’. All Google needs to do is ensure that advertisers don’t bid on the word ‘Silly Bandz’ and then have ad text that’s completely unrelated. The searchers will then let Google know whether the ad is high quality or not through their clicks.
Again, what can an advertiser do to get the best Quality Score possible? In short, not much. So don't worry about your QS. Just realize that you’re not in the driver’s seat and use your time on bidding, writing ad text, improving your landing pages and maximizing your profit, not your Quality Score.