Though recent end-to-end neural models have shown promising progress on Conversational Recommender System (CRS), two key challenges still remain. First, the recommended items cannot be always incorporated into the generated replies precisely and appropriately. Second, only the items mentioned in the training corpus have a chance to be recommended in the conversation. To tackle these challenges, we introduce a novel framework called NTRD for recommender dialogue system that decouples the dialogue generation from the item recommendation. NTRD has two key components, i.e., response template generator and item selector. The former adopts an encoder-decoder model to generate a response template with slot locations tied to target items, while the latter fills in slot locations with the proper items using a sufficient attention mechanism. Our approach combines the strengths of both classical slot filling approaches (that are generally controllable) and modern neural NLG approaches (that are generally more natural and accurate). Extensive experiments on the benchmark ReDial show our NTRD significantly outperforms the previous state-of-the-art methods. Besides, our approach has the unique advantage to produce novel items that do not appear in the training set of dialogue corpus. The code is available at \url{https://github.com/jokieleung/NTRD}.
翻译:尽管最近的端到端神经模型显示在对话建议系统(CRS)上取得了有希望的进展,但两个关键挑战依然存在。首先,建议的项目不能始终准确和适当地纳入生成的答复中。第二,只有培训材料中提到的项目有机会在对话中建议。为了应对这些挑战,我们引入了一个名为NTRD的新框架,用于建议对话系统,使对话产生与项目建议脱钩。NTRD有两个关键组成部分,即响应模板生成器和项目选择器。前者采用编码-代科德模型,以生成一个与目标项目挂钩的空位位置响应模板,而后者则使用足够的关注机制在空档地点填充适当项目。我们的方法结合了典型的空档填充方法(一般可控制)和现代NLG方法(一般比较自然和准确)的优势。关于基准ReDIal的广泛实验显示,我们的NTRD大大超越了先前的状态-艺术方法。此外,我们的方法具有独特的优势,可以制作新的项目,但不会出现在RDRDR的版本中。