Difference between revisions of "Expected value"

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(Created page with "==Definition== Given a random variable {{M|X}} we define the '''expected value''' of {{M|X}} as: * <math>\mathbb{E}[X]=\sum x\mathbb{P}[X=x]</math> {{Todo...")
 
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==References==
 
==References==
 
<references/>
 
<references/>
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==Addition of random variables==
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{{Begin Theorem}}
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Theorem: <math>\mathbb{E}[X+Y]=\mathbb{E}[X]+\mathbb{E}[Y]</math>
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{{Begin Proof}}
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{{Todo|http://www.dartmouth.edu/~chance/teaching_aids/books_articles/probability_book/Chapter6.pdf p7}}
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{{End Proof}}
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{{End Theorem}}
  
 
{{Definition|Statistics}}
 
{{Definition|Statistics}}

Latest revision as of 17:40, 8 May 2015

Definition

Given a random variable [ilmath]X[/ilmath] we define the expected value of [ilmath]X[/ilmath] as:

  • [math]\mathbb{E}[X]=\sum x\mathbb{P}[X=x][/math]



TODO: Flesh page out


References


Addition of random variables

Theorem: [math]\mathbb{E}[X+Y]=\mathbb{E}[X]+\mathbb{E}[Y][/math]