On the 25th, Google released an interesting figure on just how effective they have been keeping malware, ad spam, and misleading claims off of their network. Since 2010, Google has decreased the number of bad ads that make it through their screening process by 50%. The reason for the increase is simple; they are getting better at what they do.

In 2010, over 248,000 advertisers had their accounts suspended on Google for not complying with the terms of service, and in 2011, almost 824,000 had their accounts suspended. Google disapproved 134 million ads in 2001, versus 56.7 million ads in 2010.

Take a look at the graph from their blog site:

It is a huge challenge to keep up with all the malicious ads being submitted to Google and they are releasing this information in hopes of reassuring the public that they are ever working to address the issue.

Google explains in their blog post:

Bad ads have a disproportionately negative effect on our users; even a single bad ad slipping through our defenses is one too many. That’s why we’re constantly working to improve our systems and utilize new techniques to prevent bad ads from appearing on Google and our partner sites. In fact, billions of ads are submitted every year for a wide variety of products. We have a set of ads policies that cover a huge array of areas in more than 40 different languages. For example, because we aim to show safe, truthful and accurate ads to our users, we don’t allow ads for misleading claims, ad spam or malware.

Ads that are in violation of our ads policies aren’t allowed to be shown on Google and our AdSense partner sites. For many repeat offenders, we ban not just ads but also advertisers who seek to abuse our advertising system to take advantage of people. In the case of ads that are promoting counterfeit goods, we typically ban the advertiser after only one violation. Here are some metrics that give some insight into the scale of the impact we have had over time, showing the numbers of actions we’ve taken against advertiser accounts, sites and ads. You can see that the numbers are growing—and growing faster over time.

Here are some important improvements Google has made to their screening systems:

* Improved “query watch” for counterfeit ads: While anyone can report counterfeit ads, we’ve widened our proactive monitoring of sensitive keywords and queries related to counterfeit goods which allows us to catch more counterfeit ads before they ever appear on Google

* New “risk model” to detect violations: Our computer scanning depends on detailed risk models to determine whether a particular ad may violate our policies, and we recently upgraded our engineering system with a new “risk model” that is even more precise in detecting advertisers who violate our policies

* Faster manual review process: Some ads need to be reviewed manually. To increase our response time in preventing ads from policy-violating advertisers, we sped up our internal processes and systems for manual reviews, enabling our specialists to be more precise and fast

* Twenty-four hour response time: We aim to respond within 24 hours upon receiving a reliable complaint about an ad to ensure that we’re reviewing ads in a timely fashion

Google realizes that trust is an integral part of making their products attractive to a wide array of users. They want to make it clear they are always looking for ways to increase the quality of their products and enhance the overall user experience, and screening for bad ads is one of the most best ways they can achieve success.