there are a lot of investment funds out there. even if none possess any skill, it is possible for a few to produce extreme risk-adjusted performance simply by chance.
- One individual or fund doing well in any particular year = random chance
- One individual or fund doing well for a decade = chance is not a possible explanation
Essentially the chance of getting a heads on a coin flip is a 50/50. If you get heads, it's a chance event.
However, if you do 10,000 coin flips and end up with 8,000 heads, either the flipper or the coin have an edge in making heads turn up. The pattern shows that it is no longer a random 50:50 chance.
If a fund has 50% random chance of doing well in a particular year, then 1 of 1000 funds will do well for a whole decade purely from chance. There are thousands of funds, so existance of funds with 10/10 good years should expected even if they are purely random.
No, you are not getting the point. When you do millions of 10000 coin flips, the chance that one of them will be 8000 heads is not 50:50. Look up 'birthday paradox'.
