Humans are naturally endowed with the ability to write in a particular style. They can, for instance, re-phrase a formal letter in an informal way, convey a literal message with the use of figures of speech or edit a novel mimicking the style of some well-known authors. Automating this form of creativity constitutes the goal of style transfer. As a natural language generation task, style transfer aims at rewriting existing texts, and specifically, it creates paraphrases that exhibit some desired stylistic attributes. From a practical perspective, it envisions beneficial applications, like chat-bots that modulate their communicative style to appear empathetic, or systems that automatically simplify technical articles for a non-expert audience. Several style-aware paraphrasing methods have attempted to tackle style transfer. A handful of surveys give a methodological overview of the field, but they do not support researchers to focus on specific styles. With this paper, we aim at providing a comprehensive discussion of the styles that have received attention in the transfer task. We organize them in a hierarchy, highlighting the challenges for the definition of each of them, and pointing out gaps in the current research landscape. The hierarchy comprises two main groups. One encompasses styles that people modulate arbitrarily, along the lines of registers and genres. The other group corresponds to unintentionally expressed styles, due to an author's personal characteristics. Hence, our review shows how these groups relate to one another, and where specific styles, including some that have not yet been explored, belong in the hierarchy. Moreover, we summarize the methods employed for different stylistic families, hinting researchers towards those that would be the most fitting for future research.
翻译:自然而然地赋予人类以特定风格写作的能力。 例如, 人类可以以非正式方式重写正式信件, 以使用语言数字的形式传达字面信息, 或用语言符号来自动简化技术文章的系统来模仿一些著名作者的风格。 将这种创作形式自动化是风格传输的目标。 作为自然语言生成的任务, 风格传输的目的是重写现有的文本, 具体地说, 它创建了能显示某种需要的文体特征的引言词句。 从实际角度看, 它设想了有益的应用, 比如, 以非正式方式改写正式信件, 传达一个字面文字信息, 或用一个系统自动简化技术文章, 来模仿一些著名作者的风格。 少数个个个个性化的创意转换方法试图解决风格转换问题。 少数个调查组给出了一种方法, 但是它们并不支持研究人员专注于特定的风格。 有了这个文件, 我们的目的是全面讨论在转移任务中受到注意的风格。 我们将它们组织成一个层次, 突出每个表达的风格的风格的挑战, 而不是以非专家的风格为非专家的风格, 结构, 组织着一种结构, 结构的层次, 显示另一个结构, 结构的层次, 代表着另一个结构, 结构, 组织着另一个的层次, 结构, 结构, 显示着另一个结构, 组织, 结构, 结构, 组织, 结构, 组织, 结构, 组织, 结构, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织,,,, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织, 组织,,,,,,,, 组织, 组织, 组织, 组织,, 组织,,,,,,