Dr. Alan O'Sullivan

And I do think that...

Especially public equities got sort of the sustained bid from the AI positive story and some really good fundamental thing, but also maybe some animal spirits that came along with that in recent years.

They tend to work on average and then they are fallible.

And certainly US again is a great example of that.

And one thing, like I'm very two-handed economist.

I want to tell the positive, but I also want to highlight the weaknesses.

And one weakness also is that there really was a structural change from

Let's say K-Preso averaged something like 15 in 1900s.

And this century it's been averaging more like 30.

And again, if you are waiting for that normalization, well, tough luck.

So I think you have to be humble about that.

But at the same time, it did work.

It did work very nicely in sort of warning of the excesses at 2000 and then finding markets cheap in 2009.

So there have been success stories even over this window.

And when we look at other alternatives, there are ways of improving, let's say, K-pratio with various tricks that I go through in the paper.

But none of them is a game changer.

Ultimately, it's contrarian investing.

It tends to work, but it gets its bad experiences, and you either then throw in the towel and don't use it at all, or you accept that there is this tendency of...

sometime being too early.

And even worse, you might not be early, there might really be some structural change.