Words are Malleable: Computing Semantic Shifts in Political and Media Discourse
Table 6. Average cosine similarities of words after linear mappings on the UK parliamentary proceedings in the Thatcher period and the New York Times datasets. i and j are the source and destination spaces of the mappings. Con and Lab are Conservative and Labour. Before and after are embeddings created for before 9/11 and after 9/11.
['Dataset', 'Setting', '[ITALIC] cos( [ITALIC] WijViw, [ITALIC] Vjw)', '[ITALIC] cos( [ITALIC] WjiWijViw, [ITALIC] Viw)']
Quality of linear mappings To measure the quality of the created mappings The average similarity calculated using one-way mapping ( simij(w)=cos(WijViw,Vjw)) is low, meaning that when words are mapped from one space to the other, they are not close to the same word in the destination space. This shows that low value of similarity for one-way mapping is mainly due to instability of words which their meaning (and location in two spaces) are different based on different viewpoints.