Home  |  About Us  |  Link To Us  |  FAQ  |  Contact

# Text::NSP::Measures::2D::MI::tmi 1.03

Date Added: July 14, 2010  |  Visits: 480

Text::NSP::Measures::2D::MI::tmi is a Perl module that implements True Mutual Information. SYNOPSIS Basic Usage use Text::NSP::Measures::2D::MI::tmi; my \$npp = 60; my \$n1p = 20; my \$np1 = 20; my \$n11 = 10; \$tmi_value = calculateStatistic( n11=>\$n11, n1p=>\$n1p, np1=>\$np1, npp=>\$npp); if( (\$errorCode = getErrorCode())) { print STDERR \$errorCode." - ".getErrorMessage()."n""; } else { print getStatisticName."value for bigram is ".\$tmi_value."n""; } Assume that the frequency count data associated with a bigram < word1 >< word2 > is stored in a 2x2 contingency table: word2 ~word2 word1 n11 n12 | n1p ~word1 n21 n22 | n2p -------------- np1 np2 npp where n11 is the number of times < word1 >< word2 > occur together, and n12 is the number of times < word1 > occurs with some word other than word2, and n1p is the number of times in total that word1 occurs as the first word in a bigram. The expected values for the internal cells are calculated by taking the product of their associated marginals and dividing by the sample size, for example: np1 * n1p m11= --------- npp True Mutual Information (tmi) is defined as the weighted average of the pointwise mutual informations for all the observed and expected value pairs. tmi = [n11/npp * log(n11/m11) + n12/npp * log(n12/m12) + n21/npp * log(n21/m21) + n22/npp * log(n22/m22)] PMI = log (n11/m11) Methods calculateStatistic() - This method calculates the tmi value INPUT PARAMS : \$count_values .. Reference of an hash containing the count values computed by the count.pl program. RETURN VALUES : \$tmi .. TMI value for this bigram. getStatisticName() - Returns the name of this statistic INPUT PARAMS : none RETURN VALUES : \$name .. Name of the measure..

 Requirements: No special requirements Platforms: Linux Keyword: Libraries,  Log,  Mutual,  Npp,  Nsp,  Perl Module,  Programming,  Tmi,  True,  True Mutual Information,  Value Users rating: 0/10