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Abstract The aim of this research is the comparative evaluation of d ifferent statistical techniques employed to Automatic Text Categorization in Modern Greek. The statistical methods considered were taken from the family of multivariate data analysis methods and consist of: a) Cluster Analysis b) Multiple Linear Regression c) Discriminant Function Analysis. Furthermore, a number of d ifferent pred ictor variables were used in order to investigate their relative contribution to the overall discriminatory performance of each statistical method.

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2000, Stamatatos, Fakotakis, Kokkinakis 2001), (Cluster Analysis)

(Tambouratzis et al. 2000) (Multiple Regression) (Stamatatos,

Fakotakis, Kokkinakis 1999, Stamatatos, Kokkinakis, Fakotakis 2000). ,

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).

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(frequency profiling).

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(Principal Component Analysis) (Wiener et al. 1993)

(log likelihood) (Dunning 1993).

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(Kageura

1997).

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.

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Wilks' L F10 % 0,887 22,763 1,51746E-2114 "- 0,893 21,421 2,77415E-2025 0,909 17,890 6,22179E-1754 , 0,935 12,488 9,77125E-1277 5 0,946 10,256 1,4206E-0989 0,960 7,537 6,05704E-0793 : 0,960 7,368 8,81204E-0794 9 0,961 7,259 1,12183E-0699 10 0,963 6,826 2,92779E-06

100 11 0,965 6,544 5,45472E-06106 ; 0,966 6,228 1,09362E-05107 6 0,967 6,183 1,20659E-05111 15 0,967 6,098 1,45413E-05112 0,967 6,069 1,55028E-05116 Yule K 0,969 5,727 3,27666E-05123 12 0,972 5,200 0,00010324127 13 0,973 4,978 0,00016708131 0,977 4,240 0,000815163138 14 0,978 4,063 0,001187014140 4 0,979 3,924 0,001591351156 0,982 3,298 0,005865007160 7 0,983 3,120 0,008449015163 STTR 0,983 3,076 0,009253816165 0,983 3,072 0,00931835170 0,985 2,811 0,015814403175 0,986 2,533 0,027445062180 0,987 2,362 0,038356071186 "- 0,988 2,083 0,065315221191 1 0,989 1,954 0,083157476192 8 0,989 1,945 0,084477584193 3 0,990 1,884 0,094539568197 . . 0,991 1,548 0,172454647202 2 0,995 0,854 0,511480483

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