The study had already been criticized for seemingly comparing Facebook to a disease, as it used epidemiological models to forecast "adoption and abandonment" of online social networks (OSNs). The study posited that adoption of an OSN (i.e., signing up for) is analogous to infection and abandonment is analogous to recovery.
Again, while some parents may agree with the categorization of Facebook as a disease, not so much the company itself.
Note the somewhat sarcastic tone Facebook takes in its introduction to its own study:
Of particular interest was the innovative use of Google search data to predict engagement trends, instead of studying the actual engagement trends. Using the same robust methodology featured in the paper, we attempted to find out more about this "Princeton University" - and you won't believe what we found!Using Princeton's same methodology of tracking Google search volume, Facebook said that Princeton could lose all of its students by 2021.
In keeping with the scientific principle "correlation equals causation," our research unequivocally demonstrated that Princeton may be in danger of disappearing entirely.
The crucial error, many have pointed out, that exists in the non-peer-reviewed Princeton study is that it states the since the volume of search queries for “Facebook” began declining in 2012, there musbe be a corresponding decline in Facebook usage.
Hilariously, Facebook mocked Princeton still further. Based on Google Trends, queries "air" have also been declining steadily. Thus, Facebook said, using Princeton's methodology, by the year 2060 there will be no air left.