Results Using Word Lists A & B (Lancs) v1.1

Version 1.1 of the List Analyser was updated to include ERRT measurements. For verification we attempted to reproduce the results for the Porter stemmer as documented in a paper produced at Lancaster University by Rob Hooper (2004). A copy of the paper is in the Literature folder of this project.

The Table below shows the results for Word List A reported in Hooper's paper

Table 1

	Weak Ignored	Weak = Strong
Lovins	95.64	90.23
Porter	83.59	67.33
Paice	71.27	54.26

The Table below shows the results for Word List B reported in Hooper's paper

Table 2

	Weak Ignored	Weak = Strong
Lovins	91.79	91.47
Porter	61.66	55.08
Paice	87.97	83.13

Table 3 shows the results using Word List B (commonwords.txt)for File A and commonwords_Porter.txt for File B using List Analyser 1.1.6916, with the File> Preferences set to Normal.

See Errors in Lancaster University Stemming Evaluation Tool

Table 3

	Weak Ignored	Weak = Strong
Porter	61.61	59.81

Table 4 shows the results using Word List B and List Analyser 1.1 for the Porter stemmer with the File> Preferences set to Hooper.

Table 4

	Weak Ignored	Weak = Strong
Porter	61.61	54.99