Fast Unsupervised Dependency Parsing with Arc-Standard Transitions

Unsupervised dependency parsing is one of the most challenging tasks in natural languages processing. The task involves finding the best possible dependency trees from raw sentences without getting any aid from annotated data. In this paper, we illustrate that by applying a supervised incremental parsing model to unsupervised parsing; parsing with a linear time complexity will be faster than the other methods. With only 15 training iterations with linear time complexity, we gain results comparable to those of other state of the art methods. By employing two simple universal linguistic rules inspired from the classical dependency grammar, we improve the results in some languages and get the state of the art results. We also test our model on a part of the ongoing Persian dependency treebank. This work is the first work done on the Persian language.