It isn't, there's fanous people like Warren Buffet of course, but I personally know of 3 individuals in investing forums who post all their trades and handily beat indexes over long periods.
> Nearly a decade ago, Warren Buffett made a million-dollar bet: that by investing in a completely unmanaged, broad-market low-fee index fund, he could beat the gains earned by a high-powered hedge fund with a team of managers at the helm. His opponent was Protege Partners, LLC, a New York City hedge fund with $3.5 billion in assets under management.
[...]
> His simple Vanguard S&P 500 (VFINX) fund has delivered returns more than 40 points higher than those of the hedge fund. “I believe this is the most important investment lesson in the world,” he said.
Warren Buffet has so much money in his control that he cannot beat the market - his very investments change the value of the good companies he invests in - and not in his favor. He can make small bets of companies, but even if the bets all pay off (they will not - even great investors make mistakes) it isn't enough to be very significant.
> More dollars have flowed to index strategies that track a market benchmark, such as the S&P 500 index, partly because such funds typically have lower costs than active funds and more investors believe that stock-picking managers can't regularly beat the financial markets.
> Now a new Morningstar study, released this week at the Morningstar Investment Conference, finds that actively managed funds lagged their passive counterparts across nearly all asset classes, especially over a 10-year period from 2004 to 2014.
"Essentially nobody" is admittedly not well-defined, but I don't take it to mean that a handful of guys doing better would disprove it (and in any case have trouble finding any data points in favor of the opposite position).
I claim that the top 20% (as specified in the headline) could not be reasonably described as "essentially nobody". And the article you linked two posts ago found that more than 20% of funds beat the market.
That's over the course of a year, which is not what I would consider a long-term measure. Over the course of the year, sure, you could easily have people who beat the market.
People actually misstate the argument regularly. It is of course possible to beat the index over long periods, but there is little evidence that there is any skill that allows you to do it. That is, could those 3 individuals write down a prescriptive algorithm that allows someone to replicate their results ahead of time?
Another way to describe the problem is, given the same number of bots, randomly picking tades, as members of a trading forum, how many would beat the index? Is the number more than 3?
If there's no evidence that beating the market depends on any particular skill, that would seem to be saying it's essentially a matter of chance. If that is the case then it stands to reason that, as the period of time observed grows longer, it becomes less and less likely for anyone to beat the market.
I think you also have to define "the index". There are dozens of indexes on the NYSE alone, and many come with legitimate questions about how well they actually represent the market. In that sense, I think it is possible to choose (and not luck into) a better basket of stocks than what goes into the indexes. Of course, it isn't easy.
Warren Buffett is not a day trader. To paraphrase, "My favourite holding period is forever."
He is a good data point to demonstrate that long term investors can beat the indices. Most don't, however, and it is my understanding that day trading is even worse. Just as there are professional poker players that can consistently make money, I'm sure there are some day traders that do very well, but it is not a skill that most people have.
