Success of manufacturing companies largely depends on reliability of their products. Scheduled maintenance is widely used to ensure that equipment is operating correctly so as to avoid unexpected breakdowns. Such maintenance is often carried out separately for every component, based on its usage or simply on some fixed schedule. However, scheduled maintenance is labor-intensive and ineffective in identifying problems that develop between technician's visits. Unforeseen failures still frequently occur. In contrast, predictive maintenance techniques help determine the condition of in-service equipment in order to predict when and what repairs should be performed. The main goal of predictive maintenance is to enable pro-active scheduling of corrective work, and thus prevent unexpected equipment failures.

When a website hosting user-generated content asks users a straightforward question - "Was this content helpful?" with one "Yes" and one "No" button as the two possible answers - one might expect to get a straightforward answer. In this paper, we explore how users respond to this question and find that their responses are not quite straightforward after all. Using data from Amazon product reviews, we present evidence that users do not make absolute, independent voting decisions based on individual review quality alone. Rather, whether users vote at all, as well as the polarity of their vote for any given review, depends on the context in which they view it - reviews receive a larger overall number of votes when they are 'misranked', and the polarity of votes becomes more positive/negative when the review is ranked lower/higher than it deserves. We distill these empirical findings into a new probabilistic model of rating behavior that includes the dependence of rating decisions on context. Understanding and formally modeling voting behavior is crucial for designing learning mechanisms and algorithms for review ranking, and we conjecture that many of our findings also apply to user behavior in other online content-rating settings.

To facilitate direct comparisons between different products, we present an approach to constructing short and comparative summaries based on product reviews. In particular, the user can view automatically aligned pairs of snippets describing reviewers' opinions on different features (also selected automatically by our approach) for two selected products. We propose a submodular objective function that avoids redundancy, that is efficient to optimize, and that aligns the snippets into pairs. Snippets are chosen from product reviews and thus easy to obtain. In our experiments, we show that the method constructs qualitatively good summaries, and that it can be tuned via supervised learning.

In many areas of life, we now have almost complete electronic archives reaching back for well over two decades. This includes, for example, the body of research papers in computer science, all news articles written in the US, and most people's personal email. However, we have only rather limited methods for analyzing and understanding these collections. While keyword-based retrieval systems allow efficient access to individual documents in archives, we still lack methods for understanding a corpus as a whole. In this paper, we explore methods that provide a temporal summary of such corpora in terms of landmark documents, authors, and topics. In particular, we explicitly model the temporal nature of influence between documents and re-interpret summarization as a coverage problem over words anchored in time. The resulting models provide monotone sub-modular objectives for computing informative and non-redundant summaries over time, which can be efficiently optimized with greedy algorithms. Our empirical study shows the effectiveness of our approach over several baselines.

In this paper, we present a document visualization technique for data analysis based on the semantic representation of text in the form of a directed graph, referred to as semantic graph. It is derived using natural language processing as follows. Firstly subject– verb – object triplets are automatically extracted from the Penn Treebank parse tree obtained for each sentence in the document. Secondly, the triplets are further enhanced by linking them to their corresponding co-referenced named entity, by resolving pronominal anaphors as well as attaching the associated WordNet synset. Starting from the document's semantic graph and the list of extracted triplets we automatically generate the document summary, for which we also derive the semantic representation.