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Formula of std err Prediction

valeriel

Community Member

Joined:

Nov 29, 2013

I want to know how to transfer the formula of STD ERR OF Prediction of my linear model in Excel. ( std err Pred Formula)

I dont understand it....what is Vec quadratic ?

Formula is: Sqrt(Vec Quadratic([0.615106074605487 -0.05018339188381, -0.05018339188381 0.00428784520440499], [1] || :T20) * 194.153863605514)

T20 is my variable (temperature at 20 cm under surface)

Thank you very much for your answer!

1 REPLY
Jeff_Perkinson

Community Manager

Joined:

Jun 23, 2011

Hi Valerie,

Computing the std err of prediction involves some matrix computations that don't have a direct equivalent in Excel.

In this case Vec Quadratic(S, X) returns the diagonal elements of X * S * Transpose(X).

It appears that Excel could do the matrix multiplication using the MMULT() function and the transposition using the TRANSPOSE() function.

I can't find an Excel function which returns the diagonal elements of a matrix.

-Jeff

-Jeff