Modern Portfolio Theory

Fellas,

I was a CS/Math major in school. I am wondering what you all think of the following investment strategy (for myself):

Throw hundreds of ETF monthly returns into an excel file and have a computer program I've written calculate the combination of ETFS that has the smallest standard deviation. I'd likely do this after the scenario in Greece plays out.

I would buy and hold this strategy, likely doing some sort of rebalancing every once in awhile.

What do you guys think? If not ETFS, what other asset could I throw into the mix?

2 Comments
 
Best Response

Past results is not an indicator of future performance. Too many things wrong with your theory.

Why do you want smallest standard deviation in the first place? My guess is those ETFs will have some of the lowest returns.

What time frame are you looking at? If you don't take the ETF performance from multiple years, your results will be even more meaningless.

What ETFs will you select? Will they be randomly selected?

Why ETFs? Why not individual securities?

MPT says that if you choose securities with less risk (standard deviation), you will get lower returns. Why would you purposefully try to underperform over the long run, even if MPT was 100% true?

 

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