What is option
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An option would give a option buyer a right to buy (or sell) something from (to) the option seller 
    in the future with a pre-determined price. 

  Example 1: John paid $1.2 today to have an option to buy one 
                 IBM's stock in 3 months by paying $150. 

  Example 2: Mary paid $1.03 to sell City Group's share with a price 
                 of $40 in 3 months. 

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DuPont identity 
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                          Net Income
 ROE is defined as   = ----------------
                           Equity 
             NI
       ROE= ---                      (1)
             E

 Let times equation (1) by Sales and divide sales 

             NI   Sales
       ROE= --- * ---                (2)
             E    sales  

 Let times equation (2) by total assets and divide it by the same value 

             NI    S    A
       ROE= --- * --- * ---           (3)
             E     s    A

  Now, let's reorganize terms

             NI    S    A
       ROE= --- * --- * ---           (4)
             S     A    E

     ROE=(net income/sales)*(sales/total assets)*(total assets/equity)

     ROE = Net Profit Margin * Asset Turnover * Equity Multiplier

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What is a call option?
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A call option buyer would have a right to buy something from the option 
     seller in the future with a fixed price. 

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How to find competitors and industry ratios
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             current price
 PE ratio = ------------
               EPS

   EPS is the earnings per share 
          
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What is a put option?
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A put option buyer would have a right to sell something to the option 
     seller in the future with a fixed price. 

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multiples and stock evaluation
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Many multiples, such as PE ratio, could be 
   used to evaluation a stock's performance. 

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