Machine Translation
- Faithfulness – the meaning of the text has been preserved.
- Fluency – the translated text sounds natural to a native speaker, and also maintains the style of the original text
信达雅, 流畅且准确，这非常困难
Differences between languages
语素不一样， 语法顺序不一样， 词汇意思没有一一对应的
Task
(过时老方法）
(新方法)
算概率，极大似然估计，得到结果.
language model保证fluency, translation model保证faithfulness
evaluation
Summarization
Example
Task
Content Selection
Information Ordering
Simplifying Sentences
evaluation
