Distributions

Hello all,
I just want to check whether my understanding of howdistributions are related is right. Can somebody correct if wrong please.
(Normal distribution)^2 = Chi Square distribution
Ratio of 2 Chi Squares / their degrees of freedom = F
Normal distribution / (ratio of Chi Square / its degree offreedom)^1/2 = student t
Moreover, what is a “degree of freedom”?
I asked my lecturer and he said it characterised a ChiSquare but I didn’t really understand what he meant.
Thanks in advance.

__SB said:

Hello all,
I just want to check whether my understanding of howdistributions are related is right. Can somebody correct if wrong please.
(Normal distribution)^2 = Chi Square distribution
Ratio of 2 Chi Squares / their degrees of freedom = F
Normal distribution / (ratio of Chi Square / its degree offreedom)^1/2 = student t
Moreover, what is a “degree of freedom”?
I asked my lecturer and he said it characterised a ChiSquare but I didn’t really understand what he meant.
Thanks in advance.

Click to expand...

I don't believe some of you statements are quite correct. As an example of what I mean, see the Chi Square distribution at wikipedia
https://en.wikipedia.org/wiki/Chi-squared_distribution
where we have the
Chi Square distribution with k degrees of freedom = the sum of k independent, standard (Normal distribution)^2
So, in one sense you are correct and in another you are not. So, even if you knew this and was just being lazy about writing it out fully, you should be more careful (if you look around here enough, you'll see where I made that mistake)

As far as a degree of freedom, it is, in general, the number of 'parameters' needed to define the distribution. For example, look again at the Chi Square distribution: Since each Normal Distribution used is a standard distribution, i.e. N(0,1), the only thing left to tell us just which type our Chi Square is, is the number of N²(0,1) we use in the sum, i.e. the degrees of freedom is the number of Normal Distributions we use.

EDIT: since/sense type things