 
Summary: ICANN'99, September, Edinburgh, UK.
Learning ErrorCorrecting Output Codes from Data
Ethem Alpaydin \Lambda
Dept of Computer Engineering, Bo–gazi¸ci University, TR80815 Istanbul Turkey
alpaydin@boun.edu.tr
Eddy Mayoraz
IDIAP, CP 592, CH1920 Martigny Switzerland
mayoraz@idiap.ch
Abstract
A polychotomizer which assigns the input to
one of K – 3 classes is constructed using
a set of dichotomizers which assign the in
put to one of two classes. Defining classes
in terms of the dichotomizers is the binary
decomposition matrix of size K \Theta L where
each of the K – 3 classes is written as
errorcorrecting output codes (ECOC), i.e.,
an array of the responses of binary deci
sions made by L dichotomizers. We use lin
ear dichotomizers and by combining them
