my $positive = {
	word1 => 2,
	word2 => 4,
	word3 => 1,
};
my $negative = {
	word4 => 3,
	word5 => 1,
};

##</code><code>##

my $categorizer = Algorithm::NaiveBayes->new;

$categorizer->add_instance(
	attributes => $positive,
	label => 'positive');

$categorizer->add_instance(
	attributes => $negative,
	label => 'negative');

$categorizer->train;

##</code><code>##

my $sentence1 = {
	wordA => 2,
	wordB => 1,
};

my $probability = $categorizer->predict(attributes => $sentence1);

if ($probability->{'positive'} > 0.5) {
	# sentence1 probably positive
}
elsif ($probability->{'negative'} > 0.5) { 
	# sentence1 probably negative
}