And more about Cause and Effect

Ok, so here is another big problem with the way media reports research.  Here is a news article I found online.

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The headline reads – Facebook can Cause Depression

So of course I went off in search of the original research. It was a survey of a very large sample of undergraduate students.  Students reported on the reasons for their Facebook use (e.g. surveillance to compare their lives to those of their friends), their emotional reactions to those posts and their current mood.

The researchers have found that, feeling envious in response to other people’s posts, statistically predicted depression scores.  This word predicted is very misleading.  It gives the impression that the envy happened first.

The key point is that all of these variables are measured at the same time, so we don’t actually know which one occurred first.

It may be that envy leads to depression, but it could also be that people with depression are more likely to feel envy.

It is simply not possible to draw conclusions about cause and effect from this data.