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A Profitable and Legal Way to Game the Stock Market

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21–30 of 85 posts

Re: A Profitable and Legal Way to Game the Stock Market

#21
Sure some people get rich, but for buy and hold investors it's mostly a non-issue. The expense ratio of an S&P 500 index is still very small. A total market fund won't have the same front running issues and the expense ratios on those can actually be higher than the S&P 500 index funds.

IOW the overhead here is in the noise IMO.

Re: A Profitable and Legal Way to Game the Stock Market

#22
post #20

I expected to see (1995) tagged to the end of this article. I personally know 3 people who run their own money ( Having said that, this isn't exactly easy. You need to know 1) if a stock is going into the index 2) when its going into the index 3) how much the index will buy 4) how much the index buy will affect the price of the stock the first 3 are trivial for some index funds, though most have rules that allow them…

What kind of ROI do they get doing this? Better than 5%?

The article cites American Airlines jumping 11% in the 4 days before it was added to the S&P 500.

Re: A Profitable and Legal Way to Game the Stock Market

#23
Can't the fund "managers" just add is some slop in their buying so they don't cause such a large spike? The spike in demand is what makes this strategy possible, so spreading the demand over period of days or even a week should reduce the spike and the profitability of the strategy. I know they want their fund to match the index, but if this ever became a problem I think they could squash it pretty simply.

Re: A Profitable and Legal Way to Game the Stock Market

#24

I expected to see (1995) tagged to the end of this article. I personally know 3 people who run their own money ( Having said that, this isn't exactly easy. You need to know 1) if a stock is going into the index 2) when its going into the index 3) how much the index will buy 4) how much the index buy will affect the price of the stock the first 3 are trivial for some index funds, though most have rules that allow them…

It seems likely that someone could make some decent money shorting stocks before they leave the index funds as well.

Re: A Profitable and Legal Way to Game the Stock Market

#25
So, the writer of this article failed to give any proof other than citing the case of one specific stock (American Airlines). Even then, it failed to give any useful comparison (sure, the stock gained 11% in 4 days, but how did the rest of the market do?)

It would take a bit of effort to grab the data for all stocks entering the S&P for the last (say) 5 years, and then compare how these stocks did between the announcement and the joining of the index, but this data is vital to making the case that there is some market inefficiency here. Since the author doesn't bother to do this work, how can they justify their conclusions?

They can't even manage to get the 'easy route' right (letting someone else do the work). They cite 'one estimate' of a $4.3 billion cost but don't bother to tell use who made that estimate, giving the readers no chance to check its validity.

Lazy, lazy journalism IMO. At least quote your source, Bloomberg!

Re: A Profitable and Legal Way to Game the Stock Market

#26
The article really needs some hard numbers, not some "whitepaper estimates".

It's 500 stocks. How many randomly selected stocks do you need to almost equal the performance?

Buying a new entrant on the day it debuts is not required to come very close to matching the index performance.

The article points out that Vanguard “mitigates a good portion” of the risk by gradually building positions over time in stocks.

Problem solved.

Re: A Profitable and Legal Way to Game the Stock Market

#27
post #11
post #6

This is basically the primary trading strategy employed in the The Ugly Americans . The time period covered is mid 1990's https://en.wikipedia.org/wiki/Ugly_Americans:_The_True_Story...

Was The Ugly Americans good? I really enjoyed Bringing Down the House .

If you enjoyed Bringing Down the House, I'd say you'd pretty close to equally enjoy The Ugly Americans.

Re: A Profitable and Legal Way to Game the Stock Market

#28
Even in the worst case -- Vanguard doesn't lose anywhere near this premium -- we're talking 20-30 bps, or .25%. It's one of those scenarios where one has to choose what is less bad. Sure, an active manager could play with the index a bit more to help avoid this, but you'd be paying a lot more than .25% for his effort.

It might, however, be a good enough reason to side-step this issue and use Total Stock Market (VTSMX) instead of one based on an index that frequently drops/adds stocks.

Re: A Profitable and Legal Way to Game the Stock Market

#29
post #22
post #20

Earlier quoted context omitted.

What kind of ROI do they get doing this? Better than 5%?

The article cites American Airlines jumping 11% in the 4 days before it was added to the S&P 500.

Multiply that with nice leverage from options.

Re: A Profitable and Legal Way to Game the Stock Market

#30

So, the writer of this article failed to give any proof other than citing the case of one specific stock (American Airlines). Even then, it failed to give any useful comparison (sure, the stock gained 11% in 4 days, but how did the rest of the market do?) It would take a bit of effort to grab the data for all stocks entering the S&P for the last (say) 5 years, and then compare how these stocks did between the announc…

The source for the $4.3B is given later in the article:

"Over a course of a year, front-running -- of stocks going into and coming out of indexes -- costs investors in S&P 500 tracker funds at least 0.2 percentage points, according to research published last year by Winton Capital Management Ltd., a quantitative hedge fund that analyzed data from 1990 to 2011. That’s equal to $4.3 billion in lost income in 2014."

That paragraph includes a link to https://www.wintoncapital.com/assets/Documents/WWP_HiddenCos...

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