Experiments in newswire summarisation

In this paper, we investigate extractive multi-document summarisation algorithms over newswire corpora. Examining recent findings, baseline algorithms, and state-of-the-art systems is pertinent given the current research interest in event tracking and summarisation. We first reproduce previous findings from the literature, validating that automatic summarisation evaluation is a useful proxy for manual evaluation, and validating that several state-of-the-art systems with similar automatic evaluation scores create different summaries from one another. Following this verification of previous findings, we then reimplement various baseline and state-of-the-art summarisation algorithms, and make several observations from our experiments. Our findings include: an optimised Lead baseline; indication that several standard baselines may be weak; evidence that the standard baselines can be improved; results showing that the most effective improved baselines are not statistically significantly less effective than the current state-of-the-art systems; and finally, observations that manually optimising the choice of anti-redundancy components, per topic, can lead to improvements in summarisation effectiveness