A Wordnet from the Ground Up

42 Chapter 2. Building a Wordnet Coreprocessed by the morphological analyser Morfeusz (Woliński, 2006) 8 . The inflectionalproperties of word forms are specified in templates by the IPIC tagset codes. In keepingwith the definition of the lexico-semantic relations as linking synsets (Section 2.2),a relation must be valid for any pair of LUs from both the source and the target synset.The substitution test window lets the user choose all possible pairs of LUs (from bothsynsets) and generate instances of the test. The mechanism of tests makes plWNAppdifferent from other wordnet editing tools such as DEBVisDic, but we have not yetevaluated the influence of the substitution tests on the quality of plWordNet.The structuring of plWNApp into two main screen-perspectives (stemming from theinitial separation of broad synset construction and identification of relation instances)appeared to be incompatible with user expectations. The linguists signalled severaltimes that a serious weakness of the application was the inability to show on one screenall synsets and all relation instances to which an LU belongs, especially in the caseof relations that link LUs directly in plWordNet 9 . This request, however, is difficult tomeet without assuming the availability of very large high-resolution monitors. Somelinguists also strongly preferred keyboard interaction, and that discouraged furtherdevelopment of graph-based interface, which would require using the mouse. On theother hand, we found a two-perspective GUI quite successful in a recent extension ofplWNApp to the WordNet Weaver (Section 4.5.3).In order to improve the facilities of browsing LUs and the associated relationinstances, we introduced an additional perspective (screen) of synset editing. Thisperspective, used for browsing synsets, has a layout similar to the LU perspective:a large list of synsets on the left (rich filtering possibilities), and on the right the tabularview of the selected synset relations, plus all synset editing panels. The screen andthe LU perspective are synchronised: the filter setting and the selected synset or LU aretransferred back and forth when switching. This facilitates browsing the LU relationsof the LUs which belong to the given synset.After the construction of the initial broad synsets, we proceeded to the next step: theformation of a net of lexico-semantic relations, that is to say, the proper core plWordNet.Two main problems arose. Synsets were too wide; they included not only the expectednear-synonyms, but also hypernyms, co-hyponyms and even meronyms. Secondly,many synsets overlapped; many of such synsets belonged to the same domain, buttheir construction was separated in time and started with different LUs. The linguistshad to extract hypernyms from the existing synsets and to divide synsets into moreprecise, smaller sets, using detailed guidelines including a number of substitution tests8 The tests were shown alongside all content-adding actions, so their content was often obvious. Theusers postulated the replacement of obligatory tests with an on-demand presentation of the instantiatedtest.9 The logistic and administrative circumstances of the project made it very hard to correct that, oncethe implementation has been largely completed.