A novel approach to update summarization using evolutionary manifold-ranking and spectral clustering

Update summarization is a new challenge in automatic text summarization. Different from the traditional static summarization, it deals with the dynamically evolving document collections of a single topic changing over time, which aims to incrementally deliver salient and novel information to a user who has already read the previous documents. How to have a content selection and linguistic quality control in a temporal context are the two new challenges brought by update summarization. In this paper, we address a novel content selection framework based on evolutionary manifold-ranking and normalized spectral clustering. The proposed evolutionary manifold-ranking aims to capture the temporal characteristics and relay propagation of information in dynamic data stream and user need. This approach tries to keep the summary content to be important, novel and relevant to the topic. Incorporation with normalized spectral clustering is to make summary content have a high coverage for each sub-topic. Ordering sub-topics and selecting sentences are dependent on the rank score from evolutionary manifold-ranking and the proposed redundancy removal strategy with exponent decay. The evaluation results on the update summarization task of Text Analysis Conference (TAC) 2008 demonstrate that our proposed approach is competitive. In the 71 run systems, we receive three top 1 under PYRAMID metrics, ranking 13th in ROUGE-2, 15th in ROUGE-SU4 and 21st in BE.     

Recent advances in document summarization

The task of automatic document summarization aims at generating short summaries for originally long documents. A good summary should cover the most important information of the original document or a cluster of documents, while being coherent, non-redundant and grammatically readable. Numerous approaches for automatic summarization have been developed to date. In this paper we give a self-contained, broad overview of recent progress made for document summarization within the last 5 years. Specifically, we emphasize on significant contributions made in recent years that represent the state-of-the-art of document summarization, including progress on modern sentence extraction approaches that improve concept coverage, information diversity and content coherence, as well as attempts from summarization frameworks that integrate sentence compression, and more abstractive systems that are able to produce completely new sentences. In addition, we review progress made for document summarization in domains, genres and applications that are different from traditional settings. We also point out some of the latest trends and highlight a few possible future directions.     

CDDS: Constraint-driven document summarization models

This paper proposes a constraint-driven document summarization approach emphasizing the following two requirements: (1) diversity in summarization, which seeks to reduce redundancy among sentences in the summary and (2) sufficient coverage, which focuses on avoiding the loss of the document’s main information when generating the summary. The constraint-driven document summarization models with tuning the constraint parameters can drive content coverage and diversity in a summary. The models are formulated as a quadratic integer programming (QIP) problem. To solve the QIP problem we used a discrete PSO algorithm. The models are implemented on multi-document summarization task. The comparative results showed that the proposed models outperform other methods on DUC2005 and DUC2007 datasets.     

CLUSTERING TECHNIQUES AND DISCRETE PARTICLE SWARM OPTIMIZATION ALGORITHM FOR MULTI‐DOCUMENT SUMMARIZATION

Multi‐document summarization is a process of automatic creation of a compressed version of a given collection of documents that provides useful information to users. In this article we propose a generic multi‐document summarization method based on sentence clustering. We introduce five clustering methods, which optimize various aspects of intra‐cluster similarity, inter‐cluster dissimilarity and their combinations. To solve the clustering problem a modification of discrete particle swarm optimization algorithm has been proposed. The experimental results on open benchmark data sets from DUC2005 and DUC2007 show that our method significantly outperforms the baseline methods for multi‐document summarization.     

A spectral analysis approach to document summarization: Clustering and ranking sentences simultaneously

Automatic document summarization aims to create a compressed summary that preserves the main content of the original documents. It is a well-recognized fact that a document set often covers a number of topic themes with each theme represented by a cluster of highly related sentences. More important, topic themes are not equally important. The sentences in an important theme cluster are generally deemed more salient than the sentences in a trivial theme cluster. Existing clustering-based summarization approaches integrate clustering and ranking in sequence, which unavoidably ignore the interaction between them. In this paper, we propose a novel approach developed based on the spectral analysis to simultaneously clustering and ranking of sentences. Experimental results on the DUC generic summarization datasets demonstrate the improvement of the proposed approach over the other existing clustering-based approaches.     

MCMR: Maximum coverage and minimum redundant text summarization model

In paper, we propose an unsupervised text summarization model which generates a summary by extracting salient sentences in given document(s). In particular, we model text summarization as an integer linear programming problem. One of the advantages of this model is that it can directly discover key sentences in the given document(s) and cover the main content of the original document(s). This model also guarantees that in the summary can not be multiple sentences that convey the same information. The proposed model is quite general and can also be used for single- and multi-document summarization. We implemented our model on multi-document summarization task. Experimental results on DUC2005 and DUC2007 datasets showed that our proposed approach outperforms the baseline systems.     

基于语义的单文档自动摘要算法

单文档自动摘要的目的是在原始的文本中通过摘取、提炼主要信息,提供一篇简洁全面的摘要。自动摘要的主流方法是通过统计和机器学习的技术从文本中直接提取出句子,而单文档由于篇章有限,统计的方法无效。针对此问题,提出了基于语义的单文本自动摘要方法。该方法首先将文档划分为句子,然后计算每一对句子的语义相似度,通过运用改进型K-Medoids聚类算法将相似的句子归类,在每一类中选出最具代表性的句子,最后将句子组成文档摘要。实验结果表明,通过融合语义信息,该方法提高了摘要的质量。     

An unsupervised approach to generating generic summaries of documents

We present an optimization-based unsupervised approach to automatic document summarization. In the proposed approach, text summarization is modeled as a Boolean programming problem. This model generally attempts to optimize three properties, namely, (1) relevance: summary should contain informative textual units that are relevant to the user; (2) redundancy: summaries should not contain multiple textual units that convey the same information; and (3) length: summary is bounded in length. The approach proposed in this paper is applicable to both tasks: single- and multi-document summarization. In both tasks, documents are split into sentences in preprocessing. We select some salient sentences from document(s) to generate a summary. Finally, the summary is generated by threading all the selected sentences in the order that they appear in the original document(s). We implemented our model on multi-document summarization task. When comparing our methods to several existing summarization methods on an open DUC2005 and DUC2007 data sets, we found that our method improves the summarization results significantly. This is because, first, when extracting summary sentences, this method not only focuses on the relevance scores of sentences to the whole sentence collection, but also the topic representative of sentences. Second, when generating a summary, this method also deals with the problem of repetition of information. The methods were evaluated using ROUGE-1, ROUGE-2 and ROUGE-SU4 metrics. In this paper, we also demonstrate that the summarization result depends on the similarity measure. Results of the experiment showed that combination of symmetric and asymmetric similarity measures yields better result than their use separately.     

Multi-document summarization via submodularity

Multi-document summarization is becoming an important issue in the Information Retrieval community. It aims to distill the most important information from a set of documents to generate a compressed summary. Given a set of documents as input, most of existing multi-document summarization approaches utilize different sentence selection techniques to extract a set of sentences from the document set as the summary. The submodularity hidden in the term coverage and the textual-unit similarity motivates us to incorporate this property into our solution to multi-document summarization tasks. In this paper, we propose a new principled and versatile framework for different multi-document summarization tasks using submodular functions (Nemhauser et al. in Math. Prog. 14(1):265?C294, 1978) based on the term coverage and the textual-unit similarity which can be efficiently optimized through the improved greedy algorithm. We show that four known summarization tasks, including generic, query-focused, update, and comparative summarization, can be modeled as different variations derived from the proposed framework. Experiments on benchmark summarization data sets (e.g., DUC04-06, TAC08, TDT2 corpora) are conducted to demonstrate the efficacy and effectiveness of our proposed framework for the general multi-document summarization tasks.     

基于篇章主次关系的单文档抽取式摘要方法研究

抽取式自动文摘研究抽取文档中最能代表文档核心内容的句子作为摘要,篇章主次关系分析则是从篇章结构方面分析出篇章的主要内容和次要内容,因此,篇章主次关系分析和抽取式自动文摘存在较大关联,篇章主次关系可指导摘要的抽取。该文提出了一种基于篇章主次关系的单文档抽取式摘要方法,该方法基于神经网络模型构建了一个篇章主次关系和文本摘要联合学习的模型。该模型在考虑词组、短语等语义信息的基础上同时考虑了篇章的主次关系等结构信息,最终基于篇章内容的整体优化抽取出最能代表文档核心内容的句子作为摘要。实验结果表明,与当前主流的单文档抽取式摘要方法相比,该方法在ROUGE评价指标上有显著提高。     

A new sentence similarity measure and sentence based extractive technique for automatic text summarization

The technology of automatic document summarization is maturing and may provide a solution to the information overload problem. Nowadays, document summarization plays an important role in information retrieval. With a large volume of documents, presenting the user with a summary of each document greatly facilitates the task of finding the desired documents. Document summarization is a process of automatically creating a compressed version of a given document that provides useful information to users, and multi-document summarization is to produce a summary delivering the majority of information content from a set of documents about an explicit or implicit main topic. In our study we focus on sentence based extractive document summarization. We propose the generic document summarization method which is based on sentence clustering. The proposed approach is a continue sentence-clustering based extractive summarization methods, proposed in Alguliev [Alguliev, R. M., Aliguliyev, R. M., Bagirov, A. M. (2005). Global optimization in the summarization of text documents. Automatic Control and Computer Sciences 39, 42–47], Aliguliyev [Aliguliyev, R. M. (2006). A novel partitioning-based clustering method and generic document summarization. In Proceedings of the 2006 IEEE/WIC/ACM international conference on web intelligence and intelligent agent technology (WI–IAT 2006 Workshops) (WI–IATW’06), 18–22 December (pp. 626–629) Hong Kong, China], Alguliev and Alyguliev [Alguliev, R. M., Alyguliev, R. M. (2007). Summarization of text-based documents with a determination of latent topical sections and information-rich sentences. Automatic Control and Computer Sciences 41, 132–140] Aliguliyev, [Aliguliyev, R. M. (2007). Automatic document summarization by sentence extraction. Journal of Computational Technologies 12, 5–15.]. The purpose of present paper to show, that summarization result not only depends on optimized function, and also depends on a similarity measure. The experimental results on an open benchmark datasets from DUC01 and DUC02 show that our proposed approach can improve the performance compared to sate-of-the-art summarization approaches.     

一种基于局部二值模式的关键帧提取方法

基于旋转不变均衡局部二值模式,提出一种均衡摘要生成速度和摘要信息量的视频摘要算法。首先,使用预采样方法降低视频处理数据量,在此基础之上提取图像的局部二值模式特征;然后对两帧图像相似度进行分析,获取聚类数目。获取聚类数目之后,使用k均值算法对镜头关键帧进行聚类;最后,使用“重要度”函数评测聚类重要度,从“重要”聚类中选取聚类中心最近帧为摘要关键帧。实验结果表明,该算法生成的视频摘要在保证摘要实时性的同时,提高摘要的信息量,较好地表达了视频的内容。     

基于热传导模型的更新摘要算法

更新摘要除了要解决传统的面向话题的多文档摘要的两个要求——话题相关性和信息多样性,还要求应对用户对信息新颖性的需求。文中为更新摘要提出一种基于热传导模型的抽取式摘要算法——HeatSum。该方法能够自然利用句子与话题,新句子和旧句子,以及已选句子和待选句子之间的关系,并且为更新摘要找出话题相关、信息多样且内容新颖的句子。实验结果表明,HeatSum与参加TAC09评测的表现最好的抽取式方法性能相当,且更优于其它基准方法。     

Extractive multi-document summarization using population-based multicriteria optimization

Multi-document summarization is the process of extracting salient information from a set of source texts and present that information to the user in a condensed form. In this paper, we propose a multi-document summarization system which generates an extractive generic summary with maximum relevance and minimum redundancy by representing each sentence of the input document as a vector of words in Proper Noun, Noun, Verb and Adjective set. Five features, such as TF_ISF, Aggregate Cross Sentence Similarity, Title Similarity, Proper Noun and Sentence Length associated with the sentences, are extracted, and scores are assigned to sentences based on these features. Weights that can be assigned to different features may vary depending upon the nature of the document, and it is hard to discover the most appropriate weight for each feature, and this makes generation of a good summary a very tough task without human intelligence. Multi-document summarization problem is having large number of decision parameters and number of possible solutions from which most optimal summary is to be generated. Summary generated may not guarantee the essential quality and may be far from the ideal human generated summary. To address this issue, we propose a population-based multicriteria optimization method with multiple objective functions. Three objective functions are selected to determine an optimal summary, with maximum relevance, diversity, and novelty, from a global population of summaries by considering both the statistical and semantic aspects of the documents. Semantic aspects are considered by Latent Semantic Analysis (LSA) and Non Negative Matrix Factorization (NMF) techniques. Experiments have been performed on DUC 2002, DUC 2004 and DUC 2006 datasets using ROUGE tool kit. Experimental results show that our system outperforms the state of the art works in terms of Recall and Precision.     

主题关键词信息融合的中文生成式自动摘要研究

随着大数据和人工智能技术的迅猛发展,传统自动文摘研究正朝着从抽取式摘要到生成式摘要的方向演化,从中达到生成更高质量的自然流畅的文摘的目的.近年来,深度学习技术逐渐被应用于生成式摘要研究中,其中基于注意力机制的序列到序列模型已成为应用最广泛的模型之一,尤其在句子级摘要生成任务（如新闻标题生成、句子压缩等）中取得了显著的效果.然而,现有基于神经网络的生成式摘要模型绝大多数将注意力均匀分配到文本的所有内容中,而对其中蕴含的重要主题信息并没有细致区分.鉴于此,本文提出了一种新的融入主题关键词信息的多注意力序列到序列模型,通过联合注意力机制将文本中主题下重要的一些关键词语的信息与文本语义信息综合起来实现对摘要的引导生成.在NLPCC 2017的中文单文档摘要评测数据集上的实验结果验证了所提方法的有效性和先进性.     

基于DSC的多文本自动摘要

多文本摘要的目标是对给定的查询和多篇文本（文本集）,创建一个简洁明了的摘要,要求该摘要能够表达这些文本的关键内容,同时和给定的查询相关。一个给定的文本集通常包含一些主题,而且每个主题由一类句子来表示,一个优秀的摘要应该要包含那些最重要的主题。如今大部分的方法是建立一个模型来计算句子得分,然后选择得分最高的部分句子来生成摘要。不同于这些方法,我们更加关注文本的主题而不是句子,把如何生成摘要的问题看成一个主题的发现,排序和表示的问题。我们首次引入dominant sets cluster（DSC）来发现主题,然后建立一个模型来对主题的重要性进行评估,最后兼顾代表性和无重复性来从各个主题中选择句子组成摘要。我们在DUC2005、2006、2007三年的标准数据集上进行了实验,最后的实验结果证明了该方法的有效性。     

SFExt-PGAbs:两阶段长文档摘要模型

针对抽取式方法、生成式方法在长文档摘要上的流畅性、准确性缺陷以及在文档编码前截断原始文档造成的重要信息缺失问题,提出一种两阶段长文档摘要模型SFExt-PGAbs,由次模函数抽取式摘要SFExt与指针生成器生成式摘要PGAbs组成。SFExt-PGAbs模拟人类对长文档进行摘要的过程,首先使用SFExt在长文档中抽取出重要句子,过滤不重要且冗余的句子形成过渡文档,然后PGAbs接收过渡文档作为输入以生成流畅且准确的摘要。为获取与原始文档中心思想更为接近的过渡文档,在传统SFExt中拓展出位置重要性、准确性两个子方面,同时设计新的贪心算法。为研究不同特征提取器对生成摘要质量的影响,在PGAbs中应用两种循环神经网络。实验结果显示,在CNNDM测试集上,SFExt-PGAbs相较于基线模型生成了更为流畅、准确的摘要,ROUGE指标有较大提升。同时,子方面拓展后的SFExt也能抽取得到更准确的摘要。     

面向连贯性强化的无真值依赖文本摘要模型

自动文本摘要技术旨在凝练给定文本,以篇幅较短的摘要有效反映出原文核心内容.现阶段,生成型文本摘要技术因能够以更加灵活丰富的词汇对原文进行转述,已成为文本摘要领域的研究热点.然而,现有生成型文本摘要模型在产生摘要语句时涉及对原有词汇的重组与新词的添加,易造成摘要语句不连贯、可读性低.此外,通过传统基于已标注数据的有监督训...     

面向查询的多模式自动摘要研究

为了满足用户的个性化需求,提供尽可能丰富、实用、方便的文摘结果,该文设计了面向查询的多文档自动文摘的多种摘要模式。在将查询返回的文档集合表示为以文本、段落为节点的双层复杂网络结构以发现子主题的基础上,除传统的摘要模式外,该文又设计了概括摘要、局部摘要、全局摘要和详细摘要这四种摘要模式,并给出了各种摘要的生成方法。支持用户以主题为线索自主漫游,按照一定的逻辑顺序浏览信息。     

结合LDA和谱聚类的多文档摘要

自动文摘技术的目标是致力于将冗长的文档内容压缩成较为简短的几段话,将信息全面、简洁地呈现给用户,提高用户获取信息的效率和准确率。所提出的方法在LDA（Latent Dirichlet Allocation）的基础上,使用Gibbs抽样估计主题在单词上的概率分布和句子在主题上的概率分布,结合LDA参数和谱聚类算法提取多文档摘要。该方法使用线性公式来整合句子权重,提取出字数为400字的多文档摘要。使用ROUGE自动摘要评测工具包对DUC2002数据集评测摘要质量,结果表明,该方法能有效地提高摘要的质量。