YouTube 
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 Markowitz, InPursuit of the Perfect Portfolio: Harry M. Markowitz (34m50s)
    https://www.youtube.com/watch?v=wdeoIPCFtDU

 Modern Portfolio Theory Explained, Part 1 (10m28s)
    https://www.youtube.com/watch?v=ML48st3rD04

 Portfolio Theory: Tutorial 1 (9m39s)
    https://www.youtube.com/watch?v=lPKtI90f_sE

 Risk and Return II & Portfolio Theory I (1h18m36s)
    https://www.youtube.com/watch?v=tL7Lcl90Sc0&t=27s

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Links 
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An Excel data set
   http://canisius.edu/~yany/excel/stock11monthly.xlsx
Definition
  http://financial-dictionary.thefreedictionary.com/portfolio+theory
  http://www.yourdictionary.com/portfolio-theory
Modern Portfolio Theory (MPT)
  http://www.investopedia.com/terms/m/modernportfoliotheory.asp
  http://economistatlarge.com/portfolio-theory/introduction-to-portfolio-theory
  https://canisius.edu/~yany/markowitz.shtml
Harry Markowitz  https://en.wikipedia.org/wiki/Harry_Markowitz
Chapter 1:       http://economistatlarge.com/portfolio-theory/introduction-to-portfolio-theory
Marling, Hannes and Sara Emanuelsson,2012,The Markowitz Portfolio Theory                http://www.math.chalmers.se/~rootzen/finrisk/gr1_HannesMarling_SaraEmanuelsson_MPT.pdf
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What is a futures contract?
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What is a futures contract?
--------------------------
  A futures contract is a legal agreement to buy or sell a particular commodity or 
     asset at a predetermined price at a specified time in the future. 

  Futures contracts are standardized for quality and quantity to facilitate trading 
     on a futures exchange. The buyer of a futures contract is taking on the obligation
     to buy the underlying asset when the futures contract expires. The seller of the 
     futures contract is taking on the obligation to provide the underlying asset at 
     the expiration date. 
     https://www.investopedia.com/terms/f/futurescontract.asp

What is a S&P500 futures contract?
------------------------------
S&P 500 futures contracts give buyers the right to a basket of the stocks 
in the S&P 500 on expiration date. Priced at 250 times the index, 
they're used mostly by institutional investors. 
    http://www.cmegroup.com/trading/equity-index/us-index/sandp-500_contract_specifications.html
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