Different analytics platforms measure impressions and clicks differently. As long as the discrepancy is less than 10% (15% for mobile) that’s fine. But it’s important that you compare apples with apples, which you are not doing by comparing an ad server (Bannerflow) and a web analytics platform (Google Analytics). These are two different types of platforms and they measure data in different ways. In our experience, we often seen the web analytics report lower numbers than the ad server’s numbers. What you should look out for is if the discrepancies are consistently inconsistent. It helps to know how an ad server is counting impressions and clicks compared to a web analytics platform. For example, Bannerflow counts the click when the user clicks the ad vs. a web analytics platform that counts visits to an actual web page.
Here are a couple of reasons why there are discrepancies:
• Ad Servers report clicks that result in a redirect to a web page. There is no guarantee that the visitor makes it to the webpage or isn’t further redirected.
• The statistics are affected by a user who closes a browser after clicking an ad, hijacking (toolbars that redirect traffic), bots, and in some cases an ad server that times out. Ad servers accurately measure ad displays and clicks. They are not as accurate when telling you how many people visited a website.
• A log analyser reports on pages served by a web server, it doesn’t see pages served from caching proxies used by ISPs and doesn’t see pages served from a browser’s cache. Log analysers accurately report server activity and nothing else.
• Coding errors on the website – checking web analytics tags is laborious which means it is easy to miss something. You can use this tool to check tags http://wasp.immeria.net/
Still want to compare? Read this first
It’s important that you understand the definitions of the metrics that you are comparing. Otherwise you might end up with comparing apples with submarines (instead of apples and pears which is the best you can do if you compare an ad server and a web analytics platform). Let’s start with defining the most common levels of analysis in Google Analytics:
- A hit is a single interaction (commonly an event, pageview or transaction)
- A session is a group of hits
- A user is a group of sessions
Each of these levels of analysis has its own set of dimensions and metrics. If you want do dive deeper into these levels you can do so here
If you still are comparing data from an ad server and a web analytics platform keep this in mind:
Clicks vs. Sessions
The amount of clicks (which you get from Bannerflow) tells you how many times your banners were clicked by a user, while a session (which you can see in Google Analytics) indicates the number of unique sessions initiated by your users. A session is a group of interactions (page views, social interactions and ecommerce transactions) with your website that take place within a given time frame. You see the difference? Click on a banner and events on your web page. See how Google explains the differences between clicks and sessions.
Clicks vs. Users
Clicks still indicates how many times your banner were clicked by users, while users indicates the number of unique users that clicked your ads.
Sessions vs. Users
Google Analytics measures both sessions and users, Bannerflow does not. A session is interactions on your website within a given time frame initiated by a user to your website. If a user is inactive on your site for 30 minutes (default session time for GA) or more, any future activity is attributed to a new session. Users that leave your site and return within 30 minutes are counted as part of the original session.