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by bofadeez 208 days ago
Yeah markets are disconnected from fundamentals. Conduct causal inference with any fundamental metric on forward returns and you'll see they have almost zero predictive ability. That supports the efficient market hypothesis, as do many many other observations.

If you could simply "value the market" in some analytical way, then any simple neural network would (universally) approximate it. Instead you see the vast vast majority of machine learning quant funds fail. Here are the specific details as to why: https://www.youtube.com/watch?v=BRUlSm4gdQ4

1 comments

So how was I able to make money on both crashes this year and buy the bottom in 2022, how did Burry know it was a bubble in 2008, how did Greenspan know it in the late 1990s? Humans act irrationally, they get overconfident and overreach then things pull back, boom/busts in specific industries and whole economies have happened since the beginning of history. We humans only have so many ways to value a company and us investors all look at the same ones, we have jobs though that require us to put values to these assets for our clients. This is how human emotions and psychology gets into the market. Fama might be right it's impossible to mathematically predict the exact day and time the bubble will crash, but that doesn't mean the obvious bubble we are seeing isn't a bubble.
> So how was I able to make money

That's called "anecodtatal gambling success" and a lot of smart people suffer from this fallacy.

Applying formal causal inference procedures such as propensity score matching, doubly robust estimators, causal forests, and targeted maximum likelihood estimation (TMLE) to test whether standard fundamental variables like P/E, P/B, EV/EBITDA, ROE, ROA, gross profitability, or free cash flow yield causally influence forward equity returns consistently shows that these metrics exhibit negligible average treatment effects once confounders and colliders are controlled for.

In other words, across modern causal inference frameworks, the estimated causal impact of common fundamental signals on subsequent returns is statistically indistinguishable from zero, which indicates that most traditional fundamentals have no meaningful predictive or causal power for future price performance. There's no alternative opinion to be had. You're just wrong. You can continue gambling if you like, but you're not doing any kind of predictive analysis.