CMultiVec is a set of tools for training vector representations of words, with multiple prototypes per word. It is based on Huang Socher 2012[1]. It is designed to be as fast as possible.

It includes

• CIndexCorpus: A tool for indexing and de-indexing a corpus according to a vocab file.
• CExtractContexts: A tool for extracting context representations from a large corpus
• CClusterContexts: A tool for clustering large numbers of context representations
• CExpandVocab: A tool for generating vocabulary files and the data needed to relabel a corpus
• CRelabelCorpus: A tool for relabeling a corpus based on the context of the words.

The goal is to make multi-protype representations more accessible.

• C++11
• Boost (filesystem, program options, iostreams)
• MLPack[2]

#Tools There are four tools, which work as a pipeline. For a full listing of the command line options, just run any of the tools with the -h option.

The data formats section below will also help you understand the inputs and outputs of these tools

##CIndexCorpus If your corpus is already indexed (i.e. it contains the vocab ids of the words instead of the words themselves) you can skip this step.

##CExtractContexts CExtractContexts creates a Context Directory from a corpus. By default it will open a file for every word in the vocabulary. For a vocabulary with 100,000 words, this means you will likely need to modify your permissions in /etc/security/limits.conf to allow you to open more files simultaneously. Adding a line like

bob     hard    nofile     200000

and logging back in should do the trick.

If that is not possible, or you are having trouble with memory usage, you can limit the number of files CExtractContexts will open simultaneously using the --fcachesize option. However, note that this can significantly slow things down.

You can partition the corpus and run multiple copies of CExtractContexts at the same time outputting to separate Context Directories. To merge the context directories, simply concatenate the respective .vector files together.

##CClusterContexts CClusterContexts looks at each word in the vocabulary and forms clusters of the extracted contexts. These clusters are the different "senses" of the word.

CClusterContexts currently implements spherical K-Means clustering using the MLPack library, as well as the Halite Clustering algorithm using HaliteClustering which is included as a git submodule.

##CExpandVocab CExpandVocab uses the clustering generated by CClusterContexts to expand the vocabulary into the new expanded vocabulary file, which contains one entry for every "sense" of a word.

##CRelabelCorpus CRelabelCorpus uses the clustering generated by CCLusterContexts to relabel a corpus with the new expanded vocabulary file.

Text file, one word per line. CMultiVec has hardcoded in that and are inserted before and after every document, so make sure that they are included in your vocab file. The first word also must be the "unknown" symbol.

Text file, one floating point value per line. This will be the inverse document frequency weighting of the word in the corresponding line of the vocab file. See https://en.wikipedia.org/wiki/Tf%E2%80%93idf for more information.

Text File, D whitespace-separated floating point values per line, where D is the dimension of the word representation vectors. Each line corresponds to the representation of the same line in the vocab.

Directory containing an arbitrary number of .txt files. All of them will be processed.

Binary files named N.vectors which contain the contexts of the Nth word in the vocabulary. Contains a list of tfidf-weighted context vectors. Each vector is D IEEE-754 floats. The vectors are just concatenated and there is no padding.

Directory containing text files N.*.txt which contain the clusters generated from the contexts of the Nth word in the vocabulary.

Depending on the clustering mode, they will be in different formats.

If using the kmeans clustering mode: N.centers.txt will have on each line a whitespace separated vector, representing the center of one of the clusters.

If using the halite clustering mode: N.hlclusters.txt will be a sequence of "Beta Clusters". Each Beta Cluster will list (whitespace and newline separated)

Correlation Cluster number\n Vector of relevance\n Vector of lower bounds\n Vector of upper bounds\n

Where each correlation cluster may be composed of multiple beta clusters.

The expanded vocab file is just the same as the normal vocab file, except the different sense-clusters of a word are different entries.
The cluster number is just prepended as a two digit number to the entry.
CMultivec tools depend on the expanded vocab to be in the same order as the original vocab, and the clusters to be in numerical order. For example, it might look like

00dog
01dog
00cat
00jello
01jello
02jello

Text file, each line containing a whitespace separated vector. Each vector is the center of the corresponding line in the expanded vocabulary file. For example, if (0,1.2, 5) is on the line corresponding to 04bagel, then (0,1.2,5) is the center of the the 4th cluster of the contexts of "bagel".

@inproceedings{HuangEtAl2012,
author = {Eric H. Huang and Richard Socher and Christopher D. Manning and Andrew Y. Ng},
title = {Improving Word Representations via Global Context and Multiple Word Prototypes},
booktitle = {Annual Meeting of the Association for Computational Linguistics (ACL)},
year = 2012
}

@article{mlpack2013,
  title     = {{MLPACK}: A Scalable {C++} Machine Learning Library},
  author    = {Curtin, Ryan R. and Cline, James R. and Slagle, Neil P. and
               March, William B. and Ram, P. and Mehta, Nishant A. and Gray,
               Alexander G.},
  journal   = {Journal of Machine Learning Research},
  volume    = {14},
  pages     = {801--805},
  year      = {2013}
}

@article{10.1109/TKDE.2011.176,
author = {Robson L.F. Cordeiro and Agma J.M. Traina and Christos Faloutsos and Caetano Traina Jr.},
title = {Halite: Fast and Scalable Multiresolution Local-Correlation Clustering},
journal ={IEEE Transactions on Knowledge and Data Engineering},
volume = {25},
number = {2},
issn = {1041-4347},
year = {2013},
pages = {387-401},
doi = {http://doi.ieeecomputersociety.org/10.1109/TKDE.2011.176},
publisher = {IEEE Computer Society},
address = {Los Alamitos, CA, USA},
}