1. Monday, November 5

2. The familiar t distribution, at N-2 degrees of freedom, can be used to test the probability that the statistic r was drawn from a population with  = 0
H0 :  XY = 0
H1 :  XY  0
where
r N - 2
1 - r2
t =

3. Question
If you were to predict the height of your first child when he or she is an adult, which of the following two pieces of information would you rather know:
(1) Whether the child is a boy or a girl; or
(2) The height of the same-sex biological parent.

4. Pearson’s r -1  r  +1 -1    +1
Pearson’s r can also be interpreted as the expected value of zY given a value of zX.
tend to deviate from the mean of X when they are expressed in standard deviation units.
The expected value of zY is zX*r
If you are predicting zY from zX where there is a perfect correlation (r=1.0), then
zY=zX.. If the correlation is r=.5, then zY=.5zX.