The Lane’s Gifts vs. Google
Report part 2
Andrew Holoman
Google’s Approach to Detecting Invalid Clicks
Google’s Click Quality Team’s Mission Statement states:
Protect Google’s advertising network and provide excellent
customer service to clients by:
– Vigilantly monitoring invalid clicks/impressions and
removing its source
– Reviewing all client requests and responding in a timely
manner
– Developing and improving systems that remove invalid
clicks/impressions and properly credit clients for invalid
traffic
– Educating clients and employees on invalid
clicks/impressions
 The Click Quality Team practices this by raising the
levels of click fraud detection methods where it becomes
hard and unrewarding to commit click fraud against
Google
Strategic Objectives
Google tries to achieve these objectives in
two ways:
– Prevention

Discouraging invalid clicking activities on its
Network by making life of unethical users more
difficult and less rewarding
– Detection

Detecting and removing invalid clicks and the
perpetrators
Preventive Measures
Google tries to build mechanisms for preventing
invalid clicking that reduce inappropriate
activities and some of these are:
– Making it hard to create duplicate accounts and open
new accounts after the old ones are terminated
– Making it hard to register using false identities
– Development of certain mechanisms that
automatically reduce fraudulent activities
Characterization of Invalid Click Detection
 Online filtering vs. Offline monitoring and analysis
– Are there some time constraints on how fast the invalid click
detection should be done?
 Automated vs. Manual detection
– Were invalid clicks detected by a special-purpose software or
by human expert?
 Proactive vs. Reactive detection
– Has the detection of invalid clicks occurred before or after the
advertisers complaint ?
 Where were invalid clicks made?
 Were invalid clicks associated with the AdSense or
AdWords programs ?
Process of Detecting and Removing Invalid
Clicks
 Pre-filtering - removal of the most obvious invalid
clicks, such as “testing” and “meaningless” clicks
before they are even seen by the filters
 Online Filtering – several online filters monitor
various logs for satisfying these conditions and
detect the clicks in these logs satisfying these
conditions; such clicks are marked as “invalid”
and are subsequently removed
 Post-filtering – offline detection and removal of
invalid clicks that managed to pass the online
filtering stage
Post-filtering Sub-stages
What are the two sub-stages of postfiltering?
– Automated monitoring
– Manual reviews
Performance of Online Filters
 A true click is either valid or invalid
 Google filters can label a click as valid or
invalid
 The actual click vs. click labeling can raise
confusion within the filters
– In finding the accurate number of valid and
invalid clicks: TP+TN+FP+FN=N
– The accuracy rate is equal to (TP+TN)/N
– The error rate is equal to (FP+FN)/N
Indirect Evidence
 Two main pieces of evidence for Google’s
filters:
– Newly introduce and revised filters detect only
few additional invalid clicks
– The offline invalid click detection methods
detect relatively few invalid clicks in comparison
to the filters
Performance of Filters
 Why do Google's simple filters work well
most of the time?
– The Combination of Filters
– Extra complexity of some of the filters
– Simplicity of most of the attacks
– The Long Tail of invalid clicks
Frequency
Long Tail
Left Part
Rank
Conflict of Interest
 Two cases:
– When one particular IP address was disabled
due to inappropriate clicking activities
– The change in the double-click policy that was
considered in the Winter of 2005 and
implemented in March 2005
Automated Offline Detection
Methods
 Alerts
 Auto-termination system for publishers
Alerts
 They are used for detecting more complex
and more subtle patterns of invalid clicking
activities that may or may not be valid
– In what stage do alerts identify invalid clicks?
– What are the two types of alerts?
– What are the two ways that alerts are issued?
Auto-termination System for AdSense
Publishers
 It’s an automated offline system for
detecting the AdSense publishers who
performing inappropriate behavior by
violating the Terms and Conditions of the
AdSense program
– What are these conditions?
Manual Offline Detection
Methods
 Investigation of Advertisers
 Investigation of Publishers
Investigation of Advertisers
 Advertiser complaints: an advertiser notices
unusual clicking activities and requests Google
to investigate those activities for the presence of
invalid clicks
 Alerts: alerts detect unusual patterns of
behavior of advertisers and trigger manual
investigations of these patterns
 Customer Service Representatives: they may
request to investigate an advertiser based on
the advertiser’s request or based on their own
initiatives
Investigations of the Publishers








Publishers complaint
Advertiser’s complaint
Auto-termination system
Classifier
Detection of duplicate publishers
Second-review publishers
Customer service representatives
Requests from the Click Quality Team
Results of Investigations
 The invalid clicks are present
 No invalid clicks are present
 It is unclear if invalid clicks are present