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How to reduce ad discrepancy?

Jun 8, 2018  ·  6 min read

In the new programmatic advertising era, there are still blind spots that need to be reviewed, especially when it comes to payouts. At the end of the billing period, discrepancies are still a pretty big issue for advertisers and publishers and a real nightmare for account managers.

Discrepancy is the difference between the statistics of the publisher and the advertiser, such as ad requests, clicks, impressions, conversions.

Usually, this difference occurs due to the difference in the ad server's algorithms, but this is not the only reason. In the standard terms and conditions set out by the IAB, any discrepancy that is less than 10% is essentially water under the bridge, but when it comes to a huge budgets, even 10% discrepancy can't be ignored.

The causes of the discrepancy can be divided into the following groups:

  1. Human errors.
  2. Time differences.
  3. Technical issues.
  4. Traffic validation.

Human Errors

Discrepancies occur when most of the ad campaign setup was done manually. If you want to minimize them, fix the following issues if you have any:

  • Missing ad tags: incorrect copying of the ad tag, absence of the part of the code or the code is not completely inserted.

    The Solution: Ensure your ad codes appear throughout the site: any changes in the ad code may result in the absence of statistics and activity or the incorrect transmission of statistics.

  • Missing of macros: partially set macros, or deletion of some parameters from the tag, incorrectly set pixel tracking or passbacks.

    The Solution: Make sure that all the parameters that are requested by the advertiser are clear to you and your server has suitable macros for transferring these parameters.

    Epom Ad Server has a wide base of supported macros, an opportunity to implement pixel tracking or passback/piggyback. If there is a specific parameter that needs to be passed, it can be passed through the custom parameter. Thus you can fill any gaps in the absence of macros.

  • Differences in campaign settings: limits setup, capping, targeting by geo, OS or browser.

    The Solution: Set up limits, cappings and targeting with your partner, decide on the time of launch and end of the advertising campaign. Within Epom Ad Server, you can set all of the above, also determine OS, versions of the browser, device id and many others.

  • Launching ad code in an inappropriate website: it happens, when the publisher places a video ad in a 728x90 banner. Another example of DON'TS is to place JS ad code in Iframe, which does not allow for showing ads.

    The Solution: Decide on the ad formats and type of codes are planned for launch. At the moment, some servers, including Epom Ad Server, offer a universal solution — Universal JS, which is compatible with IFrame, JS Sync, and JS Async. By using it, there is no need to create lots of invocation codes and there is no chance of launching ad code in an inappropriate website environment.

Time zone difference

The most common reason for the discrepancy, is when ad servers operate on different time intervals or geographic time zones. For example, if Epom Ad Server is setup to report on the US (EDT) but your reporting is set-up on GMT time zone — there will always be a natural discrepancy.

The Solution: This can be avoided if you agree on the time zone on which you will be reporting or set the time zone in your account at which your publisher or advertiser works.

Technical Issues

Technical collisions can arise on the side of an ad server, publisher or advertiser.

  • Difference in the algorithm operation: each ad server can differently consider the moment when the conversion happened, ad was displayed, etc. Terminology matters: while one server considers an event to be a request another server counts it as an ad opportunity.

    The Solution: get acquainted with the proper terminology, as well as clarify with your partner how the server considers metrics.

  • Latency is another stumbling block, which means slow server operation. This is a problem when the server takes a long time to process ad request and to display an ad, often caused by the remote location of physical servers from the direct user. So if the user is in the US, and the server is in Asia, then the response time can reach an unacceptably high point.

    The Solution: Epom Ad Server has its server capacity in the US, Europe, and Asia, to reduce latency to milliseconds.

  • Heavy Creatives. Publisher's server can count the impressions while in fact, the ad did not have time to be displayed. The reason being that while ad is loading the user can close a browser or navigate to another page.

    The Solution: Always check how heavy the creative is, and if possible, see how long it takes for the creative to load.

  • Adaptation to all browsers and operating systems. If the site is not adapted for mobile OS, it may crash or display ads inappropriately. As a result, the advertiser can not consider it as an impression.
  • Caching ads on the page. Caching can lead to impression discrepancies when dealing with externally hosted creatives. If a third-party URL or ad tag is saved on a viewer's computer the first time, then the ad is seen. By default the ad will subsequently be pulled from the viewer's cache. The publisher can display the same banner several times, while the advertiser has counted only one impression. Consequently, impressions reported in the ad server are significantly higher than impressions recorded in an advertiser system.

    The Solution: This can be avoided by substituting cachebuster values in the ad code.

Traffic Validation

Over the last few years, the quantity of poor-quality inventory has skyrocketed. However, traffic validation tools do not slumber too.
Advertisers are willing to pay only for quality traffic, while craftsmen want to weld on the bot traffic. A very large percentage of discrepancy falls precisely on invalid traffic.
Bot farms, spoofing and injectors — all of them willing to earn as much as possible. At the same time, advertisers increasingly scan and filter out traffic.
Epom Ad Server uses bot filtering at an engine level: you can conduct all your activities and check the quality of the inventory in your account.
Before the launch of any ad campaign, clarify all the details about the targeting and type of the code, tools which are used to check traffic and run the test.
Check the reports on a daily basis, so you will not find yourself frustrated at the end of the month.
We hope our tips will help you minimize the discrepancies and ease your billing period stress.


Have more questions about discrepancy? Contact an Epom representative and we'll be glad to help.

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