Towards Persona-Based Empathetic Conversational Models (2020)

Abstract: Empathetic conversational models have been shown to improve user satisfaction and task outcomes in numerous domains. In Psychology, persona has been shown to be highly correlated to personality, which in turn influences empathy. In addition, our empirical analysis also suggests that persona plays an important role in empathetic conversations. To this end, we propose a new task towards persona-based empathetic conversations and present the first empirical study on the impact of persona on empathetic responding. Specifically, we first present a novel large-scale multi-domain dataset for persona-based empathetic conversations. We then propose CoBERT, an efficient BERT-based response selection model that obtains the state-of-the-art performance on our dataset. Finally, we conduct extensive experiments to investigate the impact of persona on empathetic responding. Notably, our results show that persona improves empathetic responding more when CoBERT is trained on empathetic conversations than non-empathetic ones, establishing an empirical link between persona and empathy in human conversations.

## introduction empathy, specifically affective empathy, refers to the capacity to respond with an appropriate emotion to another's mental states @xcite . in nlp, empathetic conversational models have been shown to improve user satisfaction and task outcomes in numerous domains @xcite @xcite @xcite . for example, empathetic agents received more positive user ratings, including greater likeability and trustworthiness than controls @xcite . in recent years, neural network based conversational models @xcite figure 1 : tf-idf similarity between two sets of empathetic responses @xcite for each emotion (best viewed in color). for most emotions (28 out of 32), the similarity between responses from two different speakers (blue) is substantially smaller than the similarity between two random disjoint sets of responses (orange, averaged over five runs). to this end, we propose a new task towards persona-based empathetic conversations and present the first empirical study on the impact of persona on empathetic responding. our study would be beneficial to researchers in dialogue systems and psycholinguistics. however, one major challenge of this study is the lack of relevant datasets, i.e., existing datasets only focus on either persona or empathy but not both (see we then propose cobert, an efficient bertbased response selection model using multi-hop coattention to learn higher-level interactive matching. cobert outperforms several competitive baselines on pec, including poly-encoder @xcite , the state-of-the-art bert-based response selection model, by large margins. we conduct additional comparisons with several bertadapted models and extensive ablation studies to evaluate cobert more comprehensively. finally, based on pec and cobert, we investigate the impact of persona on empathetic responding. in addition, we analyze how limited persona data improves model performance, and how our model generalizes to new personas. in summary, our contributions are as follows: ## our cobert model in this section, we briefly introduce the task of response selection and present our proposed cobert model, as shown in figure 2 . ## experiments in this section we present the datasets, baselines, experimental settings, model comparisons and ablation studies. ## conclusion we present a new task and a large-scale multidomain dataset, pec, towards persona-based empathetic conversations. we then propose cobert, an effective and efficient model that obtains substantially better performance than competitive baselines on pec, including the state-of-the-art poly-encoder and several bert-adapted models. cobert is free from hyper-parameter tuning and universally applicable to the task of response selection in any domain. finally, we present the first empirical study on the impact of persona on empathetic responding. the results reveal an empirical link between persona and empathy in human conversations and may suggest that persona has a greater impact on empathetic conversations than non-empathetic ones.