Those of you who follow news about online advertising closely are seeing plenty about the issue of "click fraud" lately. Since there's been a development in a case Google is involved in, you might like to hear about it.

As part of the settlement in the click-fraud case Lane’s Gifts v. Google, we agreed with the plaintiffs to have an independent expert examine our detection methods, policies, practices, and procedures and make a determination of whether or not we had implemented reasonable measures to protect all of our advertisers. The result of that is a 47-page report, written by Dr. Alexander Tuzhilin, Professor of Information Systems at NYU. The report was filed with the court in Texarkana, Arkansas, this morning.

The bottom-line conclusion of the report is that Google’s efforts against click fraud are in fact reasonable. At several points in his report, he calls out the quality of our inspection systems and notes their constant improvement. It is an independent report, so not surprisingly there are other aspects of it with which we don’t fully agree. But overall it is a validation of what we have said for some time about our work against invalid clicks.

Here are excerpts of some of the positive things Dr. Tuzhilin has to say about Google and invalid clicks:

“During this project, I visited Google campus three times and interviewed over a dozen of the Click Quality team members from the Spam Operations and the Engineering groups, as well as the Product Manager of the Trust and Safety Group. I found the members of both groups to be well-qualified and highly competent to perform their jobs. Most of them have relevant prior backgrounds and strong credentials.” (p.4)

“The current set of Google filters is fairly stable and only requires periodic 'tuning' and ‘maintenance’ rather than a radical re-engineering, even when major fraudulent attacks are launched against the Google Network.” (p.25)

“These inspection systems have been developed by Google over an extensive period of time and are constantly improved to extend their functionality and make them better for the investigators to do their inspections more effectively. I have personally observed several such inspections and can attest to how successfully they have been conducted by Google’s investigators. This success can be attributed to (a) the quality of the inspection tools, (b) the extensive experience and high levels of professionalism of the Click Quality inspectors, and (c) the existence of certain investigation processes, guidelines and procedures assisting the investigators in the inspection process.” (p. 40)

“Google has built the following four 'lines of defense' for detecting invalid clicks: pre-filtering, online filtering, automated offline detection and manual offline detection, in that order. Google deploys different detection methods in each of these stages: the rule-based and anomaly-based approaches in the pre-filtering and the filtering stages, the combination of all the three approaches in the automated offline detection stage, and the anomaly-based approach in the offline manual inspection stage. This deployment of different methods in different stages gives Google an opportunity to detect invalid clicks using alternative techniques and thus increases their chances of detecting more invalid clicks in one of these stages, preferably proactively in the early stages.” (p. 47)

We also filed a document with the court today that may be of interest. You can find it here. And there's more information on invalid clicks and how we manage them here and here.