๐ค AI Summary
In large-scale social media, retrieving evidence linking abstract concepts (e.g., โFreedomโ) to concrete behaviors (e.g., firearm possession) is challenging, and modeling their heterogeneous instantiations across communities remains difficult. Method: This paper proposes a retrieval-reasoningๅๅ framework that dynamically integrates BM25, dense passage retrieval (DPR), and large language model (LLM)-guided conceptual instantiation reasoning during retrieval to generate community-specific, interpretable evidence representations. Contribution/Results: It is the first work to embed LLMs directly into the retrieval pipeline, enabling dynamic search space characterization and community-adaptive deconstruction of conceptual semantics. Empirical evaluation across multiple communities demonstrates substantial gains over conventional sparse and dense retrieval baselines, effectively uncovering cognitive mechanisms and semantic evolution pathways underlying divergent conceptual expressions across demographic or ideological groups.
๐ Abstract
Finding evidence for human opinion and behavior at scale is a challenging task, often requiring an understanding of sophisticated thought patterns among vast online communities found on social media. For example, studying how gun ownership is related to the perception of Freedom, requires a retrieval system that can operate at scale over social media posts, while dealing with two key challenges: (1) identifying abstract concept instances, (2) which can be instantiated differently across different communities. To address these, we introduce ConceptCarve, an evidence retrieval framework that utilizes traditional retrievers and LLMs to dynamically characterize the search space during retrieval. Our experiments show that ConceptCarve surpasses traditional retrieval systems in finding evidence within a social media community. It also produces an interpretable representation of the evidence for that community, which we use to qualitatively analyze complex thought patterns that manifest differently across the communities.