Exploring the Relationship between Analogy Identification and Sentence Structure Encoding in Large Language Models

Identifying analogies plays a pivotal role in human cognition and language proficiency. In the last decade, there has been extensive research on word analogies in the form of ``A is to B as C is to D.'' However, there is a growing interest in analogies that involve longer text, such as sentences and collections of sentences, which convey analogous meanings. While the current NLP research community evaluates the ability of Large Language Models (LLMs) to identify such analogies, the underlying reasons behind these abilities warrant deeper investigation. Furthermore, the capability of LLMs to encode both syntactic and semantic structures of language within their embeddings has garnered significant attention with the surge in their utilization. In this work, we examine the relationship between the abilities of multiple LLMs to identify sentence analogies, and their capacity to encode syntactic and semantic structures. Through our analysis, we find that analogy identification ability of LLMs is positively correlated with their ability to encode syntactic and semantic structures of sentences. Specifically, we find that the LLMs which capture syntactic structures better, also have higher abilities in identifying sentence analogies.

ANALOGICAL -- A New Benchmark for Analogy of Long Text for Large Language Models

Over the past decade, analogies, in the form of word-level analogies, have played a significant role as an intrinsic measure of evaluating the quality of word embedding methods such as word2vec. Modern large language models (LLMs), however, are primarily evaluated on extrinsic measures based on benchmarks such as GLUE and SuperGLUE, and there are only a few investigations on whether LLMs can draw analogies between long texts. In this paper, we present ANALOGICAL, a new benchmark to intrinsically evaluate LLMs across a taxonomy of analogies of long text with six levels of complexity -- (i) word, (ii) word vs. sentence, (iii) syntactic, (iv) negation, (v) entailment, and (vi) metaphor. Using thirteen datasets and three different distance measures, we evaluate the abilities of eight LLMs in identifying analogical pairs in the semantic vector space. Our evaluation finds that it is increasingly challenging for LLMs to identify analogies when going up the analogy taxonomy.