Classification regression tree structure

Has anyone used

clasregtree

function to build a tree with numerical responses (Y)? If yes then any idea how the means (Y bar) at each leaf (terminal nodes) is calculated?

Thanks

Answer 1

[the cyclist]

Have you tried reading the documentation?

doc classregtree

or looking at the code?

edit classregtree

[Sincloe Brans]

Yes kind of did, I am not good in reading the code, hence asking for experts advise. I looked for keyword 'avg' or 'mean' which didn't show up! Eventually I need to find the observations over which each ybar is calculated at the leaf.

[the cyclist]

I don't know the function well. Are the means a standard output of the function? If so, then you should be able to trace the name of the output variable backward through the function, to see how it is calculated.

[Sincloe Brans]

Attached is the function, actually classregtree is a class which I have no idea how to edit or get the intermediate results. If you look at line 746, ybar is calculated. Any idea on how to obtain that?

[the cyclist]

I suggest you take a look at this page about debugging MATLAB.

Where you first call classregtree, you should be able to set a breakpoint, and then step through the function line-by-line to see the values all variables during the calculation.