[., .] -- Scripting, output of regression

Question

Hello all,

I'm new to JMP scripting and am working on a regression calculation based on an example in the scripting guide.

This script worked for one 64-point X-Y data set, but on a much larger data set, the script is returning "[., .]" for the beta1 variable below ([., .] is being generated by the X`*Y calculation).  X and Y are column vectors.

X2 = J(nrow(X),1) || X;

beta1 = Inv(X2`*X2)*X2`*Y;

Can anyone tell me what this output means and/or what may be going on with the script?  I have searched this forum and online and have not had success.

Cheers,

Jay

jay-p-az · Answer

MS,

Thank you for the advice.  Indeed there is a missing value in the Y column.

Jay

ms · Answer

[.,.] is a vector of missing values. The result indicates that although the matrix dimensions match X or Y contains missing values.

Try this example where Y has a missing value:

X = [1, 2, 3, 4];

Y = [1, 2, ., 3];

X2 = J( N Row( X ), 1 ) || X;

beta1 = Inv( X2` * X2 ) * X2` * Y;