$()$ The error function $(6\mathrm{.}33)$ for binary classification problems was derived for a

network having a logistic$-$sigmoid output activation function, so that $0$ y$($x$,$w$)$

$1,$ and data having target values t in $\{0,1\}.$ Derive the corresponding error function

if we consider a network having an output $1$ y$($x$,$w$)1$ and target values

t $=1$ for class C$1$ and t $=1$ for class C$2.$ What would be the appropriate choice of

output$-$unit activation function