Re:Index Investing Makes Markets and Economies More Efficien...
by stouset on Tuesday September 19, 2017 @08:04PM
(#15289765)
You're leaving out a description of how they manage to own an imbalanced quantity of A and B in the first place.
Keep in mind that this doesn't (at least not naïvely) happen when one of the two increases or decreases in value relative to the other.
Re:Index Investing Makes Markets and Economies More Efficien...
by Retric on Wednesday September 20, 2017 @08:02AM
(#15292742)
Stock buyback's are one example, but companies can also issue/aka create new stock from thin air and sell it. Though clearly less extreme than I was describing, the forces are similar.
If they own 1M$ of A and 1M$ of B, but B is worth more than A then they sell some of A to buy some of B.