[R] predict() works with the design matrix but throws error with some rows of that matrix

[peter dalgaard]

> On 20 Nov 2015, at 17:17 , Damir Cosic <damir.cosic at gmail.com> wrote:
> 
> 
> To do the same with matrix multiplication, I use the expression 1/(1+exp(-xb)):
> 
> head(1/(1+exp(-(cbind(c(1), mm) %*% coef(m)[2,]))))
> 
> which should produce the third column above, but it doesn't:
> 

I'm rusty on this, but I suspect that you need

e_i/sum(e_i)

with e_i = exp(x b_i)

(and b_1 == 0 by convention)

-pd

-- 
Peter Dalgaard, Professor,
Center for Statistics, Copenhagen Business School
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