Updating a monthly Excel data set and write an instruction 
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First, let's download the Excel data set
     http://canisius.edu/~yany/data/monthlyYan.xlsx

The structure of this date set is very simple:
      Three columns: ID, Date and Value, see the first selvera lines below. 

    ID    date         value
    --    ---------    ------
    A     11/30/1999   38.96
    A     12/31/1999   71.39
    A     1/31/2000    61.12
    A     2/29/2000    95.91
    A     3/31/2000    96.03
    A     4/28/2000    81.83
    A     5/31/2000    67.98
    A     6/30/2000    68.1
    A     7/31/2000    37.63
    A     8/31/2000    56.33

  Note 
  (1) The frequency of the data set is monthly. 
  (2) "A" is the stock ticker 
  (3) For stocks, the last column called value 
      is the monthly adjusted price. 
  (3) for SMB (Fama-French factor), value is for factor, 
         i.e., return

  Do the following things:
     (a) find out all unique ID's
     (b) update the data set
     (c) write a 2-page manual on how to use this data set
         i) how to estimate monthly returns
         ii) how to estimate annual returns
         iii) how to generate a n-stock matrix, such as 5-stocks matrix

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What does it mean 'open data'?
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Open data means the data publicly available for  
   economics, finance and accounting 

For teaching purpose, it is more than enough to use open data 

  This is one of three concepts for the Open-Source-Finance

  Kane, David, 2006, Open-Source Finance, Harvard University, 
	http://papers.ssrn.com/sol3/papers.cfm?abstract_id=966354

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Links 
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Home page for R http://r-project.org
R Packages: A Beginner's Guide
    https://www.datacamp.com/community/tutorials/r-packages-guide
Introduction to R packages
    http://r-pkgs.had.co.nz/intro.html
Introduction to R packages
    http://faculty.washington.edu/kenrice/rintro/sess08.pdf
Slides: introduction to R packages
    https://www.slideshare.net/RsquaredIn/r-programming-managing-r-packages
Introduction to R and packages
    http://pebesma.staff.ifgi.de/Aufbaukurs/R/slides_R.pdf
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