LDT is a shiny new Python library for doing two things:
- querying lots of dictionaries from a unified interface to perform spelling normalization, lemmatization, morphological analysis, retrieving semantic relations from WordNet, Wiktionary, BabelNet, and a lot more.
- using the above to explore and profile word embeddings, i.e. the cool distributional representations of words as vectors.
If you have never heard about word embeddings -- you're missing out, here's an introduction. If you have, head over to the project website for some new research results. And if you don't care about word embeddings, you can still just use LDT as a supplement to NLTK, SpaCy, and other great NLP tools.
Note: LDT is in active development; all the dictionary functionality for English and scripts for running experiments are already available. Integration with vecto library and optimization are coming in the nearest weeks; please update your installation often. You can also join the discussion group to discuss your results and get notified about new releases!
Install and configure ldt, and run this sample script (and/or change it to tweak the resources used for relation detection):
python3 -m ldt.experiments.default_workflowThe output will be something like this:
| LD score | CBOW | GloVe | SG |
| SharedMorphForm | 51.819 | 52.061 | 52.9 |
| SharedPOS | 30.061 | 35.507 | 31.706 |
| SharedDerivation | 4.468 | 3.938 | 5.084 |
| Synonyms | 0.413 | 0.443 | 0.447 |
| Antonyms | 0.128 | 0.133 | 0.144 |
| Hyponyms | 0.035 | 0.035 | 0.038 |
| OtherRelations | 0.013 | 0.013 | 0.013 |
| Misspellings | 13.546 | 9.914 | 12.809 |
| ProperNouns | 30.442 | 27.278 | 27.864 |
| CloseNeighbors | 3.102 | 0.16 | 2.278 |
| FarNeighbors | 25.209 | 49.934 | 21.41 |
The numbers here indicate percentage of neighbor vectors that held the indicated relation with each target word in the sample. The information is coming from a ton of dictionaries (see below), and you can fine-tune which ones you want to use.
LDT profile explains what kinds of information your embedding model actually captures. That can help you predict how your model will do on a particular task, and also give some ideas about how it can be improved. Check out the results of a large-scale experiment with 60 embeddings and 21 datasets.
And yes, you heard it right, you can use your own vocabulary sample - the one that actually makes sense for whatever downstream task you're optimizing for!
Note:
The current implementation queries online resources, so a large experiment will take time. Stay tuned, we're working on making it faster. The distribution analysis is currently provided only for embeddings trained on our pre-processed Wikipedia dump, which is also available in dependency-parsed version. Functionality for computing distriburional information from any other corpora is coming.
The main function of LDT is automatic detection of linguistic relations that could possibly hold in a pair of words. This super-complicated procedure can now be performed in one click:
>>> relation_analyzer = ldt.relations.RelationsInPair() >>> relation_analyzer.analyze("black", "white") {'Hyponyms': True, 'SharedMorphForm': True, 'SharedPOS': True, 'Synonyms': True, 'Antonyms': True, 'ShortestPath': 0.058823529411764705, 'Associations': True}
It goes without saying that white and black are not always antonyms. Context dependence is something we're thinking about, stay tuned for future work.
The above information comes from a ton of various dictionary resources. You can access all combined information about any given word in one click:
>>> encapsulation = ldt.Word("encapsulation") >>> encapsulation.pp_info() ======DERIVATIONAL INFO====== Stems : capsulate, encapsulate, capsule Suffixes : -ion, -ate Prefixes : en-OtherDerivation : RelatedWords : encapsulation, capsule review, glissonian capsule, capsular, capsulate ======SEMANTIC INFO====== Synonyms : encapsulation Antonyms : Meronyms : Hyponyms : Hypernyms : physical_process, status, condition, process ======EXTRA WORD CLASSES====== ProperNouns : False Noise : False Numbers : False URLs : False Hashtags : False Filenames : False ForeignWords : False Misspellings : False Missing : False
To provide this, LDT queries various old and new resources. Accordingly, they are all now accessible from a unified Python interface, making LDT usable in other NLP research areas as a companions to NLTK.
A few quick highlights of ldt resources:
>>> wiktionary = ldt.dicts.semantics.Wiktionary() >>> wiktionary.get_relation("white", relation="synonyms") ['pale', 'fair'] >>> wikisaurus = ldt.dicts.semantics.Wikisaurus() >>> wikisaurus.get_relations("cat", relations="all") {'synonyms': ['tabby', 'puss', 'cat', 'kitty', 'moggy', 'housecat', 'malkin', 'kitten', 'tom', 'grimalkin', 'pussy-cat', 'mouser', 'pussy', 'queen', 'tomcat', 'mog'], 'hyponyms': [], 'hypernyms': ['mammal', 'carnivore', 'vertebrate', 'feline', 'animal', 'creature'], 'antonyms': [], 'meronyms': []} >>> babelnet = ldt.dicts.semantics.BabelNet() >>> babelnet.get_relations("senator", relations=("hypernyms")) {'hypernyms': ['legislative_assembly', 'metropolitan_see_of_milan', 'poltician', 'legislative_seat', 'senator_of_rome', 'band', 'the_upper_house', 'polictian', 'patres_conscripti', 'musical_ensemble', 'presbytery', 'politician', 'pol', 'solo_project', 'policymaker', 'political_figure', 'politican', 'policymakers', 'archbishop_emeritus_of_milan', 'deliberative_assemblies', 'ensemble', 'career_politics', 'soloproject', 'list_of_musical_ensembles', 'legislative', 'roman_senators', 'archbishopric_of_milan', 'politicain', 'rock_bands', 'section_leader', 'musical_organisation', 'music_band', 'four-piece', 'roman_catholic_archdiocese_of_milan', 'upper_house', 'archdiocese_of_milan', 'band_man', 'milanese_apostolic_catholic_church', 'legistrative_branch', 'group', 'solo-project', 'music_ensemble', 'law-makers', 'roman_senator', 'legislative_arm_of_government', 'solo_act', 'patronage', 'roman_catholic_archbishop_of_milan', 'bar_band', 'senate_of_rome', 'deliberative_body', 'see_of_milan', 'legislative_fiat', 'musical_group', 'ambrosian_catholic_church', 'legislature_of_orissa', 'legislative_branch_of_government', 'list_of_politicians', 'senatorial_lieutenant', 'roman_catholic_archdiocese_of_milano', 'legislature_of_odisha', 'bandmember', 'assembly', 'archdiocese_of_milano', 'bishop_of_milan', 'ensemble_music', 'solo_musician', 'musical_duo', 'legislative_branch_of_goverment', 'first_chamber', 'politicians', 'legislative_bodies', 'political_leaders', 'politico', 'music_group', 'legislative_body', 'career_politician', 'legislature', 'rock_group', 'legislative_power', 'diocese_of_milan', 'musical_ensembles', 'musical_organization', 'revising_chamber', 'archbishops_of_milan', 'political_leader', 'deliberative_assembly', 'conscript_fathers', 'five-piece', 'catholic_archdiocese_of_milan', 'pop_rock_band', 'senatrix', 'deliberative_organ', 'polit.', 'roman_senate', 'legislative_politics', 'bishopric_of_milan', 'legislative_branch', 'musical_band', 'archbishop_of_milan', 'legislatures', 'general_assembly', 'musical_groups', 'instrumental_ensemble', 'politition', 'patres', 'upper_chamber', 'solo-act', 'conscripti', 'legislator']}
>>> derivation_dict = ldt.dicts.derivation.DerivationAnalyzer() >>> derivation_dict.analyze("kindness") {'original_word': ['kindness'], 'other': [], 'prefixes': [], 'related_words': ['kindhearted', 'kindly', 'in kind', 'kindliness', 'kinda', 'many-kinded', 'first-of-its-kind', 'kind of', 'kindful', 'kindless'], 'roots': ['kind'], 'suffixes': ['-ness']}
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Reliable lemmatization with productive rules and Wiktionary/BabelNet: ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
WordNet lemmatizer is limited by the size of its lexical base, even when the morphological pattern is straightforward.
>>> morph_metadict = ldt.dicts.morphology.MorphMetaDict() >>> morph_metadict.lemmatize("GPUs") ['GPU']
Vector neighborhoods are often full of pre-processing noise and misspellings. LDT does its best to clean up some straightforward cases:
>>> analyzer = ldt.dicts.normalize.Normalization() >>> analyzer.normalize("%grammar") {'lemmas': ['grammar'], 'found_in': ['wordnet'], 'word_categories': ['Misspellings'], 'pos': ['noun']} >>> analyzer.normalize("gram-mar") {'found_in': ['wordnet'], 'lemmas': ['grammar'], 'word_categories': ['Misspellings'], 'pos': ['noun']} >>> analyzer.normalize("grammarlexicon") {'found_in': ['wordnet'], 'lemmas': ['grammar', "lexicon], 'word_categories': ['Misspellings'], 'pos': ['noun']}
LDT also provides the option of correction of frequent misspelling patterns (only for high-certainty cases):
>>> spellchecker_en = ldt.dicts.spellcheck.SpellcheckerEn() >>> spellchecker_en.spelling_nazi("abritrary") 'arbitrary'
If something doesn't work, open an issue on GitHub.
Yes, LDT is multilingual! At least, as far as querying semantic relations goes. LDT supports BabelNet, the largest multilingual dictionary resource available -so everything they have is retrievable. Many of the other LDT modules (particularly morphology) are language-specific, and only English is fully supported at the moment. However, the infrastructure for adding other languages is already in place, so if you can find or create e.g. lists of affixes for your language, development would be easy. Get in touch if you'd like to get involved.
Legal caveat: LDT is open-source free software. No hamsters were harmed in its production, and no harm should come from its usage. However, no guarantees of any kind.