Probability Distributions – Finite RV’s Random variables first introduced in Expected Value def. A finite random variable is a random variable that can assume only a finite number of distinct values Example: Experiment-Toss a fair coin twice X( random variable)- number of heads X can assume only 0, 1, 2
Probability mass function
Probability mass function(p.m.f)- Small f
Cumulative distribution function(c.d.f)
Cumulative distribution function(c.d.f)- Big F
Calculating Probabilities-Using p.m.f & c.d.f
p.m.f
Expected value –Finite R.V
Probability Distributions – Continuous RV’s
Probability density function-p.d.f
p.d.f
Relationship between Probability & Area of p.d.f - for Continuous R.V
Important
c.d.f
Uniform random variable
p.d.f for uniform random variable
c.d.f for uniform random variable
Expected value for uniform random variable
Example for Uniform random variable
Graph of p.d.f for uniform
Graph of c.d.f for uniform
Exponential random variable
p.d.f/c.d.f/ expected value – Exponential random variable