Measuring the compositionality of noun-noun compounds over time
Table 2: Spearman’s ρ of our measures and the compositionality ratings of REDDY.
['[EMPTY]', 'modifier-mean', 'head-mean', 'compound-mean']
The overall highest correlation occurs between compound-mean and LMI with ρ of 0.54. We also see that sim-bw-constituents and sim-with-heads are generally good predictors as well. Contrary to Schulte im Walde et al. we do not find a strong correlation between modifiers and the REDDY ratings. Interestingly, PPMI is always weakly negatively correlated with the ratings. This could be due to PPMI’s property of inflating scores for rare events. but on par with a replication study by Schulte im Walde et al. We speculate that these differences are potentially due to the use of different data sets, the fact that we use a considerably smaller context window for constructing the word vectors (5 due to the restrictions of Google Ngram corpus vs. 100 in Reddy et al. im Walde et al.