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Related to stemmer: stemming, Porter stemmer


(information science, human language)
A program or algorithm which determines the morphological root of a given inflected (or, sometimes, derived) word form -- generally a written word form.

A stemmer for English, for example, should identify the string "cats" (and possibly "catlike", "catty" etc.) as based on the root "cat", and "stemmer", "stemming", "stemmed" as based on "stem".

English stemmers are fairly trivial (with only occasional problems, such as "dries" being the third-person singular present form of the verb "dry", "axes" being the plural of "ax" as well as "axis"); but stemmers become harder to design as the morphology, orthography, and character encoding of the target language becomes more complex. For example, an Italian stemmer is more complex than an English one (because of more possible verb inflections), a Russian one is more complex (more possible noun declensions), a Hebrew one is even more complex (a hairy writing system), and so on.

Stemmers are common elements in query systems, since a user who runs a query on "daffodils" probably cares about documents that contain the word "daffodil" (without the s).

(This dictionary has a rudimentary stemmer which currently (April 1997) handles only conversion of plurals to singulars).
References in periodicals archive ?
With the judges looking for an application that increased productivity while also considering design, safety and creativity, Stemmer Imagng was declared the winner for 'not only picking up an existing project, but completely overhauling it, thanks to a depth of understanding of the particular application'.
10) Los dos autores que mejor exponen esta concepcion son Gauthier (1986) y Stemmer (2000).
Keywords: Index technique, Inverted files, Urdu Language, Urdu Stemmer, Morphological rules
A stemmer strips the words of a text down to their basic forms so that English walking is stripped down to walk.
Stemmer niega la existencia de imperativos categoricos, ya que sostiene que el deber siempre esta necesariamente vinculado a un querer.
Using up to 4 area scan cameras and 2 linescan cameras from Stemmer Imaging, CapaCom detects pores, blow holes and other damage to complex cast components and inspects several thousand components in three shifts each day.
Tatzber M, Stemmer M, Spiegel H, Katzlberger C, Haberhauer G, Gerzabek MH (2008) Impact of different tillage practices on molecular characteristics of humic acids in a long-term field experiment An application of three different spectroscopic methods.
The tour has been organised by the Missing Voices consortium, made up of Birmingham-based Ulfah Arts - which recently launched a beautiful booklet illustrating a trail through the Museum & Art Gallery's Islamic art collections - Holland's Marmoucha and Denmark's Tavse Stemmer.
The tour has been developed by the Missing Voices group made up of artists from Ulfah Arts, a Birmingham-based organisation which develops arts initiatives for women of all faiths, Marmoucha in Holland and Tavse Stemmer based in Denmark.
The GB-Series' plug-and-play system supports Windows (2000, XP and Vista), Linux, QNX, Matrox, National Instruments, Stemmer Imaging, Norpix and MVTec.
Postmistress Marilyn Stemmer, 54, Darlington: "It is outdated and unfair.
We analyse the output, the size of the database, and then propose the future implementation of a part of speech tagger and word stemmer into the program to improve its linguistic performance.