Not every discrepancy indicates an error
Valid data are the basis for meaningful analyses and well-founded decisions. If data is compared between different web analytics solutions, between web analytics and backend systems or between web analytics and ad server evaluations, the following must be considered:
1. Ignore minimal discrepancies
Discrepancies of less than 5% should be considered normal. Even with identical processing procedures and key figure calculations, the position of the tag in the HTML of the page or the distances to the different data centres can cause minor discrepancies.
2. Understand marginal deviations
Even discrepancies of 5-10% are not uncommon and are not necessarily an indication of faulty implementations or reporting problems. The following aspects can cause justified discrepancies:
- Advertising marketers usually measure clicks directly through the publisher page or advertising medium, while web analytics is only used on the landing page (except when redirect links are used). If the visitor closes the browser window or tab very quickly, no recording takes place on the target page.
- Clicks, visits and visitors are different things in different solutions. While the definition of clicks should be the same, the calculation of visits and visitors is often based on different logics and techniques, e.g. end of visit only based on time-outs or visitor recognition using cookies, fingerprints, user IDs or session IDs.
- By default, etracker Analytics respects the DoNotTrack signals of the browsers. Other solutions do not offer this option or require special settings for this.
- Data collection can also be prevented by “strict” data protection settings in browsers or “private” windows as well as additional advertising and tracking blockers.
- With etracker Analytics, traffic from known bots and spiders is automatically filtered out. With other solutions, the exclusion of bot traffic must be activated.
- Discrepancies due to payment service providers such as PayPal, Amazon Payments and credit cards can be minimised, but not completely avoided. The reason for the discrepancies is that customers can cancel the return to the shop page after the external payment process, despite the “auto-return” setting.
- With other solutions, discrepancies can occur due to sampling, especially in the case of high traffic. Also, in the case of tracking that requires consent, an extrapolation is sometimes made from the consented users to the totality of all visits. Neither of these apply to etracker Analytics.
3. Investigate significant discrepancies
If the discrepancies exceed the 10% threshold, possible sources of error beyond the aspects listed under point 2 should be investigated. In most cases, high deviations are due to incorrect implementations. The following questions need to be answered:
- Is the execution of the etracker code incorrectly blocked by the Consent Management?
The type of interaction with the CMP (i.e. pre- or post-consent tracking) has a huge impact on data collection. The etracker code contains integrated cookie blocking as standard and should therefore be excluded from blocking by the CMP. See also our instructions on the correct integration of etracker Analytics in CMPs. - Is the etracker code implemented correctly on all pages and are all pages recorded uniquely?
If the page titles are not unique or pages are only differentiated by URL parameters, the default settings must be adjusted or code parameters used. The special requirements for AMP pages, single page applications and the like must also be taken into account.
- Does the CSP header of the website possibly not allow parameterisation?
The Content Security Policy (CSP) may incorrectly block the execution of the etracker code or cause it not to work correctly.
- Is campaign tracking and especially SEA tracking implemented correctly?
SEA traffic is automatically assigned to the SEA medium if the SEA campaigns have not been provided with UTM or etracker parameters in the Suffix field of the final URL.
When testing, please make sure that you have not excluded yourself from the measurement by IP blocking or by means of an opt-out cookie!
Once you have checked all the above aspects, you can count on your etracker analysis data.
Our consulting experts will also be happy to help you in the form of an individual and thorough implementation check-up. It is best to repeat this regularly – as is customary for motor vehicles – every 2-3 years in order to benefit fully from all etracker innovations and possibilities.