They don’t mention being survivorship-bias free, which I would expect them to if they were.
I’m not commenting on that study which I have not read, but merely point out that it is possible to do such studies right.
Yes, I agree it’s possible to do them correctly. But few people do, and finding positive results is so much more likely if you do them wrong that poor methodology should be the default explanation for any such positive result.
They don’t mention being survivorship-bias free, which I would expect them to if they were.
I’m not commenting on that study which I have not read, but merely point out that it is possible to do such studies right.
Yes, I agree it’s possible to do them correctly. But few people do, and finding positive results is so much more likely if you do them wrong that poor methodology should be the default explanation for any such positive result.