Harvard statistics, video 9 note(expectation & indicator)

8:37 2014-10-08 Wednesday
start Harvard statistics, video 9


expectation & indicator r.v.


8:38 2014-10-08
averages(means, expected values)


9:05 2014-10-08
weighted average


9:07 2014-10-08
the simplest thing we can start is Bernoulli


X ~ Bernoulli(p)


9:11 2014-10-08
indicator r.v.


9:13 2014-10-08
X ~ Bin(n, p) // Binomial


9:15 2014-10-08
Linearity: the single most useful property of expectation


9:21 2014-10-08
Hypergeometric distribution


9:31 2014-10-08
E(X) = E(X1 + X2 + ... + Xn) // example of r.v.s


9:33 2014-10-08
that's the fundamental bridge


9:35 2014-10-08
in this case it's dependent, but linearity says


it's still true


9:36 2014-10-08
Geometric distribution:


Geom(p): independent Bernoulli(p) trials, count #failures


         before the 1st success.