What Is Ad Discrepancy?

Table of Contents

• What Is Ad Discrepancy?

• How to Calculate Discrepancy? 

• How Does Ad Discrepancy Occur?

• How to Reduce Ad Discrepancy ?

What Is Ad Discrepancy?

Ad discrepancy is the term used for data inconsistency while tracking data. To put it simply, It is the difference in ad requests between the ad servers of both publisher and advertiser.

Ad Discrepancy

How to Calculate Discrepancy? 

The formula to calculate ad discrepancy, regardless of the metric, is:

Ad Discrepancy = | Advertiser Impressions – Publisher Impressions | / Advertiser Impressions x 100%

How Does Ad Discrepancy Occur?

Ad discrepancies can occur in programmatic advertising due to various reasons such as differences in ad server reporting, Latency, ad-blocking, ad fraud, Human errors  and discrepancies between analytical tools used by publishers and advertisers.

• Latency

Ad latency is the delay between when an Ad request is made and when the Ad is fully loaded and displayed to the  Distance between a hosting server and user and ad server latency are a couple of factors that affect page loading time.

• Ad server reporting

Ad servers have different methods for counting impressions, leading to discrepancies in the number of impressions reported. For instance, one ad server may count an impression when the ad is fully loaded, while another ad server may count it when the ad starts to load.

• Ad-blocking 

Ad-blocker extensions/software prevents ads from being displayed to users. For Instance, If a webpage delivers 1000 impressions and 15% of users installed Ad blockers to their system. Then, the adblocker will prevent 150 impressions from being served to user which might lead to discrepancy.

• Incorrect Macros

Each ad server has their own macros predefined. To track the data correctly, Ensure the macros like cache-buster and click macros are properly implemented. For Instance, Implementing the cache-buster to Ad tag will call the ad request each time a person visits your site, then the ad server loads ad units, instead of the web browser cache doing so. 

• Different Geographical Definitions

Different ad servers map IP address location data differently, which can lead to significant discrepancies.

• Ad Fraud

Ad fraud occurs when bots or malwares are used to generate fake impressions/clicks. These fraudulent impressions can inflate the number of impressions served and result in discrepancies in reporting.

• Time zone Difference

Most reporting tools don’t provide real-time data. For instance, an advertiser using an EAT time zone. If he is working with a site owner who is in the EC time zone, the latter will be generating reports by 10 pm daily.

How to Reduce Ad Discrepancy ?

• Ad Validation/Verification

Certain traffic validation/verification tools and platforms can help to owe to their bot filtering feature, scanning, and removing invalid traffic. 

• Ensure Proper Macros

Ensure the cache-buster and click macros are implemented correctly in the Ad tags.

• Daily Reports

Consistently look into the discrepancy% and make changes like blacklisting any partner or exchange if there is a signal of abnormal behavior.

• A/B Testing

Run bucket testing to pinpoint the cause for discrepancy. Try to test with different various parameters like day, Ad size, Time zone, Geography, Device etc.