# how to create Chi squared distribution using mean and variance?

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Khoder Makkawi on 16 Dec 2019
Edited: Vladimir Sovkov on 16 Dec 2019
Hello,
I have the mean and the variance for a Chi squared distribution.
I want to create this Chi squared distribution using the mean and the variance that I have, can I ?
Thank you.

Vladimir Sovkov on 16 Dec 2019
see https://www.mathworks.com/help/stats/chi-square-distribution-1.html

Vladimir Sovkov on 16 Dec 2019
You probably mean the variance of the normally distributed variable x. Then , , and its variance is the number of the degrees of freedom (number of independent measurements of x) n, which is the integer number. What do you really have, and what do you want?
Khoder Makkawi on 16 Dec 2019
What I have is the mean and the variance of the distributed variable x.
What I want is to plot the Chi squared distribution that represents these data.
But I don't know how to do that using the mean and the variance.
Vladimir Sovkov on 16 Dec 2019
If you want to approximate your x with the variance of 0.01 via chi^2, then it is quite impossible--the variance of chi^2 must be integer. If you want to construct the new chi^2 variable based on your x implying it is normally distributed - see my earlier comment.