Hyalella faxoni Stebbing, 1903 from Costa Rica is redescribed. The species was previously in the synonymy of Hyalella azteca (Saussure, 1858). The morphological differences between these two species are discussed.

Mada andeana, a new species from the Andes is here described. Diagnostic characters are illustrated for both male and female. Mada durantae González et Gómez is here synonymized with Mada inepta (Gorham), new synonymy.

Eleven new replacement names in the genus Mesochorus Gravenhorst, 1829 are proposed due the synonymy with Plectochorus Uchida, 1933 and Stictopisthus Thomson, 1886 made by Wahl in his cladistic analysis of the genera of Mesochorinae.

Reinholdina deelemanorum Giachino & Moravec, 2009 is a junior synonym of Parapropus neumanni Müller, 1911. The genus Reinholdina Giachino & Moravec, 2009 is placed in the synonymy with Parapropus Ganglbauer, 1899.

Zipf's law states that if words of language are ranked in the order of decreasing frequency in texts, the frequency of a word is inversely proportional to its rank. It is very reliably observed in the data, but to date it escaped satisfactory theoretical explanation. This article suggests that Zipf's law may result from a hierarchical organization of word meanings over the semantic space, which...

In his development of formal semantics for natural language Montague [1970a]– Montague [1973], Richard Montague modeled the meaning (Frege’s sense) of a term A by its Carnap intension CI(A), the function which assigns to each state a, specifying a “possibleworld”, “time” and“context of use”, the denotationden(A)(a) of A in that state. Now this is surely not right: among other things, it makes “...

Recent work on the problem of detecting synonymy through corpus analysis has used the Test of English as a Foreign Language (TOEFL) as a benchmark. However, this test involves as few as 80 questions, prompting questions regarding the statistical significance of reported results. We overcome this limitation by generating a TOEFL-like test using WordNet, containing thousands of questions and comp...

The genus and its five known species are redescribed P. jicaquei sp. nov. is described. Synonymies include beckeri Zang, 1905 with opacipennis (Thompson, 1857) (new synonymy), mandibularis Casey, 1914 burmeisteri Kuwert, 1891 magister 1897 mniszechi Kaup, 1868 densipennis kraatzi 1898 synonymy). We a phylogenetic analysis, keys for larvae adults, biogeographic information each species. occurs f...

In this paper we describe a comparison among three systems that estimate semantic similarity between words: Latent Semantic Analysis (Landauer & Dumais, 1997), Pointwise Mutual Information (Turney, 2001), and Generalized Latent Semantic Analysis (Matveeva, Levow, Farahat, & Royer, 2005). We compare all these techniques on a unique corpus (TASA) and, for PMI and GLSA, we also report performance ...

We have developed an interactive query refinement tool that helps users search a knowledge base for solutions to problems with electronic equipment. The system is targeted towards non-technical users, who are often unable to formulate precise problem descriptions on their own. Two distinct but interrelated functionalities support the refinement of a vague, non-technical initial query into a mor...