notes

Personal notes
git clone git://git.laack.co/notes.git
Log | Files | Refs

IteratedExpectations.md (616B)


      1 # Iterated Expectations
      2 
      3 L12
      4 
      5 **Definition:** The law of iterated expectations states the expected value of a conditional expectation is the unconditional expectation. 
      6 
      7 Simply, this means that when finding the expectationt of some random variable we can sum the weighted expectation for its base components. 
      8 
      9 Let's say we have a PDF that is 1/3 from 0-1 is height and 1-2 has a height of 2/3. We can then find the expectation of the first component (0-1) and multiply it by the probability of the grouping (1/3) and then sum this with all other components in the same manner to find the unconditional probability.