TechTalks from event: NAACL 2015

2A: Generation and Summarization

  • Transition-Based Syntactic Linearization Authors: Yijia Liu, Yue Zhang, Wanxiang Che, Bing Qin
    Syntactic linearization algorithms take a bag of input words and a set of optional constraints, and construct an output sentence and its syntactic derivation simultaneously. The search problem is NP-hard, and the current best results are achieved by bottom-up best-first search.One drawback of the method is low efficiency; and there is no theoretical guarantee that a full sentence can be found within bounded time.We propose an alternative algorithm that constructs output structures from left to right using beam-search.The algorithm is based on incremental parsing algorithms. We extend the transition system so that word ordering is performed in addition to syntactic parsing, resulting in a linearization system that runs in guaranteed quadratic time. In standard evaluations, our system runs an order of magnitude faster than a state-of-the-art baseline using best-first search, with improved accuracies.
  • Extractive Summarisation Based on Keyword Profile and Language Model Authors: Han Xu, Eric Martin, Ashesh Mahidadia
    We present a statistical framework to extract information-rich citation sentences that summarise the main contributions of a scientific paper. In a first stage, we automatically discover salient keywords from a paper's citation summary, keywords that characterise its main contributions. In a second stage, exploiting the results of the first stage, we identify citation sentences that best capture the paper's main contributions. Experimental results show that our approach using methods rooted in quantitative statistics and information theory outperforms the current state-of-the-art systems in scientific paper summarisation.
  • HEADS: Headline Generation as Sequence Prediction Using an Abstract Feature-Rich Space Authors: Carlos A. Colmenares, Marina Litvak, Amin Mantrach, Fabrizio Silvestri
    Automatic headline generation is a sub-task of document summarization with many reported applications. In this study we present a sequence-prediction technique for learning how editors title their news stories. The introduced technique models the problem as a discrete optimization task in a feature-rich space. In this space the global optimum can be found in polynomial time by means of dynamic programming. We train and test our model on an extensive corpus of financial news, and compare it against a number of baselines by using standard metrics from the document summarization domain, as well as some new ones proposed in this work. We also assess the readability and informativeness of the generated titles through human evaluation. The obtained results are very appealing and substantiate the soundness of the approach.