Facebook says that it has uncovered bugs in its Page Insights product that has impacted impression and reach reporting for some of its users. It stresses that these issues have impacted reporting only and not delivery, and it hasn’t affected Ad Insights. Now that it has diagnosed the problem, the company says it will be rolling out a fix starting today and over the weekend.

Page Insights is the analytics service that allows Facebook Page administrators to receive aggregated anonymous insights about user activity on their Page. In a sense, you might think of it as Google Analytics for the social network.

It’s hard to determine the real impact of these bugs as Facebook says it will vary from Page to Page and also day to day because it’s based on a number of factors, including when something is posted and how frequently. It advises that admins review their individual Pages and look at the organic, paid, and viral reach and impressions for the Page and posts between now and the next few weeks.

For those that have sent complaints to the social network stating that they’re having issues with Page Insights, Facebook says that it won’t be able to backfill the reports with historical data.

Naturally, the inability to add back historical data might unnerve Page admins, especially those who have come to rely on the Insights to help in their reporting to their bosses or clients about the effectiveness of a campaign or online presence. Facebook says that it recognizes the impact this issue will have with brands and says that it’s “taking this very seriously” and has already implemented additional quality and verification measures to prevent future bugs and resolve them quickly.

Snap 2013 02 22 at 09.40.16 730x376 Facebook confirms Page Insight bugs led to misreported analytics with fix rolling out today

Last February, there was some questions about the accuracy of Facebook Insights, which led the social media data company PageLever to launch a site called WhyIsFacebookInsightsNotWorking.com to let you know how far back reporting is. In accessing the site today, we saw that it’s saying Insights are behind three days.

In the end, Facebook says that when the fix is implemented, it expects most Pages to see its total reach to stay the same or increase. Additionally, if Pages are running News Feed ads, paid reach should also increase. Unfortunately it cannot determine the impact on organic reach because of a variety of factors. Lastly, the company says that some Pages will see a change in metrics computed from reach and impressions, such as engagement rate and virality.

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