# Thread: Q re t and f distributions

1. ## Q re t and f distributions

Ok, so usually we're asked to derive the t of f distribution, that itself is fine. Lately there's been a part b to each that I need help with.

Re the t distribution - "What kind of density does T^2 have?"

And re the f distribution

If G is an F r,x (F subsript r,x) type of random variable, what type of random variable is H = I/G ?

2. Originally Posted by okthenso
Ok, so usually we're asked to derive the t of f distribution, that itself is fine. Lately there's been a part b to each that I need help with.

Re the t distribution - "What kind of density does T^2 have?"
[snip]
The technique used in the below two threads can be used:

http://www.mathhelpforum.com/math-he...functions.html

http://www.mathhelpforum.com/math-he...tml#post119542

Originally Posted by okthenso
[snip]
And re the f distribution

If G is an F r,x (F subsript r,x) type of random variable, what type of random variable is H = I/G ?
What is I?

3. Would it make more sense if the I was 1 ? It doesn't mention it anywhere else in the question. Very hard to tell even when I zoom in on it...

If $X$ ~ $F(\nu_1, \nu_2)$ then $\frac{1}{X}$ ~ $F(\nu_2, \nu_1)$.