
What is this called?
 Random vector
 (there are three random variables in this random vector)


Given the joint distribution, you can find any marginal information that you want
T/F
True

Given marginal information, you cannot calculate the joint unless...?
They are independent

What are the two most commonly used measures of association between random variables?

What is the covariance computing formula?


Why is covariance difficult to interpret compared to correlation?
 Covariance has units, so interpretation is difficult
 Correlation is unitless


What is indicated when ?
then X and Y are uncorrelated (Not Independent!!!)

What is the value of ρ when X and Y are independent?
(Alternately, If given rho=0, it translates to X and Y being uncorrelated, not independent!)

What is the range of correlation?

What does this indicate?
an exact linear relationship

When it reasonable to use a binomial distribution when a hypergeometric distribution would normally otherwise be considered?
When sample size is small relative to our population size

point mass
A probability distribution with unity probability mass at one specific outcome, and zero probability mass everywhere else


A binomial distribution can be represented by a ___?____ when n is large
Poisson




