Tweaking your Google Ads Quality Score with negative keywords

The quality score is one of the greatest features for google to optimize their revenues. Yes, it is a blackbox - but when you keep in mind that optimizing revenue is the main target google wants to achieve with the Quality Score, then we can reengineer what has to happen somehow.

Click-Through-Rate is still the most important KPI

It is pretty simple: If you pay a very high bid but your CTR on top is zero, then google is not earning money. Google has to punish you with a low quality score to disappear from the top position. When the system is trained with enough click data we have a situation that should look like this: for a given user query the sum of Impressions*CTR*CPC for all auction members should be maximized.

When the position data was still available in google ads, it was possible to calculate a normalized CTR (the most simple approach: Normalized CTR = Position * CTR). After that transformation we are able to look at CTRs on any given position.

The higher the normalized CTR was the higher the Quality Score was. It was that simple.

Low sample sizes are also a problem for google when they try to optimize their system

New queries every day and also low sample queries makes it difficult to optimize the system, even for google. For that reason I'm sure that they do some aggregations to make good estimations:

• Instead of looking on query level, the CTR data of the keyword is used (that can trigger a lot of different queries - in some cases not always homogeneously when it comes to relevancy for query->keyword matching)
• Google introduced the PostClickQualityScore (besides some other QS components) for a reason: They want to give you a better understanding which aspects do affect the Quality Score. How google is able to set a PostClickQualityScore? If the users click on an ad and bounces right away, google realizes this when the user is back in the google search. If the bounce rate of one ad is above average - I would lower the quality score without knowing the competitors CTR (that haven't made it to top 3 positions yet) and after a while new ads are shown and google has new observations for the ads that were outside the Top 3 before. Very important for a learning system!

Let's take this two things and combine them to our advantage!

Save wasted money immediately and optimize your quality score within the next weeks by using negative keywords

As I described here (https://www.dhirubhai.net/pulse/stop-wasting-your-google-ads-budget-approach-setting-neefischer/) there is a strong correlation of bounce rates and conversion rates. If you block all n-grams with high bounce rates on query level, the remaining traffic will be of higher quality. Google will see right away that the users clicking your ad, stay longer on your page and do not bounce that often. The PostClickQualityScore and probably also the Keyword Quality Score will change.

Reducing Bounce-Rate = Increasing Post Click Quality Score = Increasing total Quality Score

In my case I observed a Bounce Rate reduction of -15% (measured in Google Analytics) after applying the ngram negative list with high bouncing search patterns. In the google Quality Scores the Post Click Quality Score went up by +28% - the Keyword Quality Score by +9%. The Search Predicted CTR went up by +16%, Creative Quality Score improved by +7%.

Without changing anything in CPC Bids the Average CPC was -12% lower compared to the time period before without the negative list. Pretty nice after 10 days, isn't it?