230 likes | 363 Views
A Word at a Time. Computing Word Relatedness using Temporal Semantic Analysis. Kira Radinsky , Eugene Agichteiny , Evgeniy Gabrilovichz , Shaul Markovitch. A rich source of information can be revealed by studying the patterns of word occurrence over time Example: “peace” and “war”
E N D
A Word at a Time Computing Word Relatedness using Temporal Semantic Analysis Kira Radinsky, EugeneAgichteiny, EvgeniyGabrilovichz, ShaulMarkovitch
A rich source of information can be revealed by studying the patterns of word occurrence over time • Example: “peace” and “war” • Corpus: New York Times over 130 years • Word <=> time series of its occurrence in NYT articles • Hypothesis:Correlation between 2 words time series • Semantic Relation • Proposed method: Temporal Semantic Analysis (TSA) Introduction
3 main steps: • Represent words as concepts vectors • Extract temporal dynamics for each concept • Extend static representation with temporal dynamics Temporal Semantic Analysis
c : concept represented by a sequence of words wc1,…,wck • d : a document • ε : proximity relaxation parameter (ε = 20 in the experiments) • c appears in d if its words appear in d with a distance of at most ε words between each pair wci, wcj • Example: “Great Fire of London” 2. Temporal dynamics
t1,…,tn : a sequence of consecutive discrete time points (days) • H = D1,…,Dn: history represented by a set of document collections, where Di is a collection of documents associated with time ti • the dynamics of a concept c is the time series of its frequency of appearance in H 2. Temporal dynamics
Compare by weighted distance between time series of concept vectors • Combine it with the static semantic similarity measure Using TSA for computing Semantic Relatedness
t1, t2 : words • C(t1) = {c1,…,cn}and C(t2) = {c1,…,cm}: sets of concepts of t1 and t2 • Q(c1,c2) : function that determines relatedness between two concepts c1 and c2 using their dynamics (time series) Algorithm
Pearson's product-moment coefficient: • A statistic method for measuring similarity of two random variables • Example: “computer” and “radio” Cross Correlation
Measure similarity between 2 time series that may differ in time scale but similar in shape • Used in speech recognition • It defines a local cost matrix • Temporal Weighting Function Dynamic Time Warping
New York Times archive (1863 – 2004) • Each day: average of 50 abstracts of article • 1.42 Gb of texts • 565 540 distinct words • A new algorithm to automatically benchmark word relatedness tasks • Same vector representation for each method tested • Comparison to human judgment (WS-353 and Amazon MTurk) Experimentations: Setup
Two innovations: • Temporal Semantic Analysis • Anew method for measuring semantic relatedness of terms • Many advantages (robustness, tunable, can be used to study language evolution over time) • Significant improvements in computing words relatedness Conclusion