This study is a great example of how you can use the data you have available to talk yourself into your conclusions. The implicit point of the study is to refute the "5% of Twitter accounts are spam" stat from Twitter's 10-Q that was the basis of his putting the twitter acquisition "on hold".

Except - the baseline that they choose is entirely NOT comparable to that of Twitter's baseline. The study says:

> Followerwonk selected a random sample from only those accounts that had public tweets published to their profile in the last 90 days, a clear indication of “activity.” Further, Followerwonk regularly updates its profile database (every 30 days) to remove any protected or deleted accounts. We believe this sample is both large enough in size to be statistically significant, and curated to most closely resemble what Twitter might consider a monetizable Daily Active User (mDAU).

Except that we know what Twitter defines as a monetizable DAU:

> We define monetizable daily active usage or users (mDAU) as Twitter users who logged in and accessed Twitter on any given day through Twitter.com or Twitter applications that are able to show ads.

Nothing about posting, nothing about engagement at all - simply: were you able to see an ad?

So there isn't any reason to claim that this "might" represent what Twitter uses as an mDAU - we know, in fact, that is not how they measure it. A more honest statement would have been:

"We selected a random sample of (etc. etc.). We believe that this sample is large enough to be significantly significant, however, it can not be compared to Twitter's mDAU set, as it does not count passive consumers of Twitter content. Instead, this data can be used to suggest that a significant amount of the total posted content on Twitter is delivered by bots"

My guess is the number of consumers of content is greater than the posters of content by several orders of magnitude, though some of that would be mitigated by the longer time horizon.