Brittany Thompson started an excellent discussion on the looming PPC click fraud problem, "Have You Been a Victim of Click Fraud?" http://www.webproworld.com/viewtopic.php?t=22173
We at Clicklab have developed a score-based system for fighting click fraud. We call it Click Inflation Index.
The system applies a number of tests to each user session on your website, much like spam filters do with emails. Penalty points are assigned to the session for each failed test. If the cumulative penalty score exceeds the threshold, user session is tagged as inflated. Click Inflation Index is a share of user sessions tagged this way vs. total user sessions, expressed as a percentage.
Here is a brief summary of the click fraud tests you can apply:
- Test 1. Visit depth, expressed in the number of pageviews or time spent on site.
- Test 2. Visitors per IP triggers penalty if ratio for a particular IP exceeds the control by certain percentage.
- Test 2a. Paid clicks per IP works same way as 2, only applies to paid clicks.
- Test 3. No cookie - no play? We think you should penalize a user session if it doesn't accept cookies.
- Test 3. Pageview frequency helps to differentiate between human user sessions and auto-clickers.
- Test 4. Anonymous proxy servers should definitely trigger a penalty.
- Test 5. Geographic origin. You may want to penalize countries from which you never have and likely never will receive a viable lead.
- Test 6 and beyond. Finesse and customize. You can devise your own triggers and assign points to them.
Additional details can be found in this WebProNews article: http://www.webpronews.com/ebusiness/...lickFraud.html
Have you been using other methods of detecting and documenting PPC click fraud? What other tests would you apply in your particular situation?