ie total area under graph = certancy = 1
ie probability of x being between a and b
= Expected value of x = ( average)
= Varience of x = ( standard deviation)
Normal Distribution
Often applies where sample size is
large.
0.3 Probability density = P(x)
=
0.2
0.1
PoissonDistribution
probability of r events in time t
= average no of
events in time t
mean =
varience =
Exponential Distribution
E(x) =
V(x) =
