Can a crystal ball make you rich?
By James Parkyn - PWL Capital - Montreal
Markets are tough to predict even with advance information
Imagine owning a crystal ball that lets you see tomorrow’s news in advance. You could cash in and get rich!
Not so fast, says statistician and financial writer Nassim Nicholas Taleb, author of best-seller The Black Swan: The Impact of the Highly Improbable. “If you give an investor the next day’s news 24 hours in advance, he would go bust in less than a year,” he warns.
Taleb’s assertion now has backing from a study by Victor Haghani and James White of financial management firm Elm Wealth.
WSJ trading experiment
They did an experiment with 118 U.S. university graduate students—90% in finance or MBA programs—to test Taleb’s claim.
The students each got $50 and the front page of the Wall Street Journal (with market price data blacked out) published on 15 random days from 2008 to 2022. They then got the chance to bet on how the S&P 500 Index and 30-year U.S. Treasury bonds would do the next day.
They could go either long (that is, bet the market would go up) or short (bet that it would go down). They were also allowed to use leverage of up to 50 times—meaning they could borrow to increase the size of their trades to potentially make (or lose) more money.
Students broke even
The study’s “Crystal Ball Trading Challenge” (which you can try yourself here) showed how hard it is to predict the markets—even if you have advance knowledge. The students grew their $50 to $51.62, meaning an average return of only 3.2%. The result was statistically indistinguishable from breaking even, the paper noted.
Just under half of the students (45%) lost money, while 16% went bust. The players made winning trades only 51.5% of the time.
While students bet on the direction of bonds correctly 56.2% of the time, they were right about the S&P 500 in just 48.2% of the trades. Moreover, they compounded their errors by using more leverage in their stock’s bets (where they were wrong more often) than in bonds trades.
Ordinary participants lost 30%
As middling as these results were, however, the students fared much better than the roughly 1,500 people who played the game on the study authors’ website. These participants’ median result was a 30% loss. Only 40% made a profit, and 36% lost everything.
The study, titled “When a Crystal Ball Isn’t Enough to Make You Rich,” also included results from a select group of five very seasoned and successful traders from top organizations. They all made a profit, with a median gain of 60%.
But even they were often wrong. They placed losing bets 37% of the time. The study found that they did better than the students mostly because of how they strategically used position sizes to place bigger bets when they had more confidence.
“Taleb is right”
These seasoned professionals’ superior results suggested that “there are teachable skills involved in successful discretionary investing,” the study said.
But for the vast majority of people, “by and large we think Taleb is right,” the authors concluded.
“It’s very humbling,” Haghani was quoted saying about the results. “Even if you have the news in advance, it’s still really hard to do asset allocation or whatever with a high chance of being right, let alone not knowing what’s going to happen.”
Timing the market is a gamble
The study is just another good example of how hard it is to guess what markets will do. Even advance information appears to be unhelpful for most people, and it may actually be ruinous for some.
And in the real world where we don’t have the next day’s news, timing the market is even more of a gamble.
Investing shouldn’t be about gambling. Data shows you’re better off with a diversified portfolio and long-term investment plan that you stick to with discipline. This can help you tune out the headlines and better capture the returns that the markets have to offer.
We can leave the crystal balls for the carnival.
Read more commentary and insights on personal finance and investing in our past blog posts, eBooks and podcast on the website of PWL Capital’s Parkyn-Doyon La Rochelle team and on our Capital Topics website.