Bug in MSE output of General LS Linear Fit.vi?

Hi: In the General LS Linear Fit.vi, output MSE. Help for the vi describes the formula as (I attached a picture, but I'm not sure if it will appear in the post), but it looks like something is missing, because if I use the formula to my input values, I get a match only if all input Standard Deviations are 1's. As Standard Deviations increase, this formula gives me smaller MSE, higher MSE if Standard Deviations decrease; but I noticed MSE of the vi doesn't change so much, and every time all input Standard Deviations have the same value (no matter how large or small they are), MSE returns to the same original value.
According to the formula, MSE is inverse proportional to the square of Standard Deviations, no way to return to original value if they're changed. Is this formula correct or shuld it be different?
Attachments:
untitled6.jpg ‏5 KB

Hi, Karunya:
I actually rechecked my stuff, and I found that the formula that Mehak_D showed me in
MSE formula.JPG
is correct and really works. and the one I found in one of the LV 5 help files were wrong
untitled6.jpg
I'm attaching 2 pictures showing the LV5 Help file where I found it, as well as the Index where I clicked to open it. Just let me know if the formula were corrected in the Help file for later LV versions.
Thank you very much.
Attachments:
General LS Linear Fit Theory.jpg ‏96 KB
Help Index.jpg ‏34 KB

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