Robert J. Shiller writes: In a new book, the authors describe an investment environment populated by increasingly sophisticated analysts who rely on big data, powerful computers, and scholarly research. With all this competition, “the hurdles to achieving alpha [returns above a risk-adjusted benchmark – and thus a measure of success in picking individual investments] are getting higher and higher.”
That conclusion raises a key question: Will alpha eventually go to zero for every imaginable investment strategy? More fundamentally, is the day approaching when, thanks to so many smart people and smarter computers, financial markets really do become perfect, and we can just sit back, relax, and assume that all assets are priced correctly?
This imagined state of affairs might be called the financial singularity, analogous to the hypothetical future technological singularity, when computers replace human intelligence.
The implication is that Buffet’s genius could be replicated by a computer program that incorporates these factors.
If that were true, investors would abandon, en masse, their efforts to ferret out mispricing in the market, because there wouldn’t be any. Market participants would rationally assume that every stock price is the true expected present value of future cash flows, with the appropriate rate of discount, and that those cash flows reflect fundamentals that everyone understands the same way. Investors’ decisions would diverge only because of differences in their personal situation.
There is a long-recognized problem with such perfect markets: No one would want to expend any effort to figure out what oscillations in prices mean for the future.kets were perfect, smart money would give up trying.
Markets seem to be driven by stories of great new eras and of looming depressions. There are fundamental stories about technology and declining resources. And there are stories about politics and bizarre conspiracies.
No one knows if these stories are true, but they take on a life of their own. Sometimes they go viral. When one has a heart-to-heart talk with many seemingly rational people, they turn out to have crazy theories. These people influence markets, because all other investors must reckon with them; and their craziness is not going away anytime soon.
Maybe Buffett’s past investing style can be captured in a trading algorithm today. But that does not necessarily detract from his genius. Indeed, the true source of his success may consist in his understanding of when to abandon one method and devise another.
Human judgment, good and bad, will drive investment decisions and financial-market outcomes for the rest of our lives and beyond.
