Revisiting Statistical Laws of Semantic Shift in R omance Cognates (2022)

Abstract: This article revisits statistical relationships across Romance cognates between lexical semantic shift and six intra-linguistic variables, such as frequency and polysemy. Cognates are words that are derived from a common etymon, in this case, a Latin ancestor. Despite their shared etymology, some cognate pairs have experienced semantic shift. The degree of semantic shift is quantified using cosine distance between the cognates’ corresponding word embeddings. In the previous literature, frequency and polysemy have been reported to be correlated with semantic shift; however, the understanding of their effects needs revision because of various methodological defects. In the present study, we perform regression analysis under improved experimental conditions, and demonstrate a genuine negative effect of frequency and positive effect of polysemy on semantic shift. Furthermore, we reveal that morphologically complex etyma are more resistant to semantic shift and that the cognates that have been in use over a longer timespan are prone to greater shift in meaning. These findings add to our understanding of the historical process of semantic change.

## introduction the romance languages, such as present-day french, italian, and spanish, are sister languages which evolved from vulgar latin @xcite . they share numerous cognates, that is, words derived from a common etymon: for instance, the latin verb habere "to have" developed into avoir (fr), avere (it), and haber (es). 1 whereas french and italian still maintain the original meaning "to have", it is no longer used as such in spanish, where it is primarily used as an auxiliary to form perfect tense, while the notion of possession is generally expressed with tener. likewise, the meanings and functions of some cognate pairs have diverged despite their common etymology. in the current paper, we investigate factors at play in semantic shift foot_1 using a computational approach. in recent years, the analysis of diachronic semantic change using computational methods, inter alia, distributed representation of words, has gained increasing research interest @xcite @xcite @xcite @xcite @xcite @xcite . the degree of lexical semantic shift has been conventionally quantified using cosine distance between relevant words, represented in the form of embeddings. a number of researchers have investigated the relationships between semantic change and frequency, polysemy, or prototypicality @xcite @xcite . however, these effects have since been called into question @xcite . following this line of research, the present study revisits statistical relationships across romance cognates between semantic shift and six intralinguistic variables, including frequency and polysemy. for this purpose, we apply regression analysis and compare partial regression coefficients of individual variables while controlling for the others. by employing cognates, we are able to investigate whether particular trends hold across all explored languages. for the sake of simplicity, we assume that their common ancestor, latin, was uniform at the primitive stage before it developed into the romance languages, although in reality latin was not immune to variation across time, geography, or social stratification @xcite . our principal contributions are three: (i) amending flaws in the past research, we demonstrate that the law of conformity and the law of innovation @xcite both hold for romance cognates; (ii) exploring hitherto unexplored attributes of latin etyma, we reveal that cognates whose etyma are morphologically more complex are more resistant to semantic shift; and (iii) considering temporal gap between words in lexical incorporation to a language, we show that words that have been in use over a longer timespan are prone to diverge more in meaning. the rest of the paper is organized as follows. in section 2, we review related research and point out its shortcomings. section 3 describes our improved methodology. in section 4 we present the experimental setup and results, followed by discussion in section 5. section 6 concludes the paper, pointing to future research directions. ## related work two studies deserve special mention; both of them tackled statistical analysis of diachronic semantic change using word embeddings. a milestone in the field was @xcite , who analyzed historical corpora in several languages and proposed two laws concerning semantic change: one is the law of conformity, according to which frequency is negatively correlated with semantic change; the other is the law of innovation, stating that polysemy is positively correlated with semantic change. however, these laws, as well as that of prototypicality @xcite , were revised @xcite on the grounds that (i) the effect of frequency turned up even under control conditions, where no correlation was to be expected; and (ii) polysemy and prototypicality as they were defined by that research were highly collinear with frequency. inquiry into romance cognates was first pursued by @xcite and later extended in @xcite . in contrast to @xcite , @xcite witnessed a positive correlation between frequency and degree of semantic shift; words that underwent more semantic shift tend to be more frequent. however, the ex-periments were conducted under non-comparable setups. unlike @xcite , who used cosine distance, @xcite quantified the magnitude of semantic shift with what they denominated "falseness score." this value was calculated by subtracting the similarity score for a non-cognate translation pair (e.g., long "long" (fr) -largo "id." (es)) from the one for a cognate pair judged as false friends (e.g., long (fr)luengo "id. (erudite wording)" (es), both tracing back to longu) foot_2 . false friend refers to either of two cognates in different languages that have diverged semantically despite their common etymology @xcite . focusing on false friend pairs inevitably translates into exclusion of the cognate pairs that preserve commonality in meaning; this would prevent us from gaining insights on general tendencies across overall cognate pairs. in addition, the use of falseness scores was hardly justified. accordingly, it is imperative to settle the dispute over the diametric effect of frequency by implementing experiments under identical conditions, such that genuine cognate pairs as well as false friend pairs are covered. furthermore, there is still room for improvement. first, @xcite defined polysemy of a romance word as the number of synsets in word-net that the word is part of. thus, the polysemy score of a cognate pair was computed as the average of number of synsets for the two words in question. however, if the ultimate goal is to determine factors that could induce semantic shift, it is more appropriate to consider polysemy prior to eventual semantic shift. second, @xcite leveraged publicly available multilingual word embeddings @xcite . notwithstanding their usefulness, however, there is a risk that the embeddings are undesirably affected by the alignment algorithm employed; if a cognate pair is aligned in advance, then it naturally becomes more similar than it should be. ## regression analysis we applied linear regression analysis to explore statistical relationships between the degree of semantic shift and six intra-linguistic factors, detailed below. for the pair-wise scatter plots between the standardized variables, see appendix a. ## conclusions in this study, we revisited statistical relationships between semantic shift and intra-linguistic variables across the romance languages. our principal contributions are three: (i) we demonstrated that the law of conformity and the law of innovation @xcite both hold for romance cognates by amending flaws in the past research; (ii) we revealed that cognates whose etyma are morphologically more complex are more resistant to semantic shift by exploring hitherto unexplored attributes of latin etyma; and (iii) we showed that words that have been in use over a longer timespan are prone to diverge more in meaning by considering temporal gap in lexical incorporation to a language. one limitation of our study is a lack of comparison with latin. without it, we would not have a complete picture of historical semantic change; we need to understand how much and in what direction it has evolved. to meet this aim, it is a sine qua non to obtain latin embeddings trained upon classical latin sources, thereby allowing for direct comparisons with the romance ones. also, it will be an interesting extension to elucidate types of semantic change that have occurred in relevant cases @xcite , such as specialization, generalization, melioration, and pejoration @xcite . in addition, we need to address qualitative difference in meaning, including typicality, hypernymy, and hyponymy, since we did not go further in this paper than to define polysemy as the number of word sense entries in the dictionary. such an improvement could be achieved by taking advantage of information in wordnet.