866 research outputs found
From Databases to Information Systems
Research and business is currently moving from centralized databases towards information systems integrating distributed and autonomous data sources. Simultaneously, it is a well acknowledged fact that consideration of information quality_IQreasoning _is an important issue for large-scale integrated information systems. We show that IQ-reasoning can be the driving force of the current shift from databases to integrated information systems. In this paper, we explore the implications and consequences of this shift. All areas of answering user queries are affected – from user input, to query planning and query optimization, and finally to building the query result. The application of IQ-reasoning brings both challenges, such as new cost models for optimization, and opportunities, such as improved query planning. We highlight several emerging aspects and suggest solutions toward a pervasion of information quality in information systems.Peer Reviewe
Profiling relational data: a survey
Profiling data to determine metadata about a given dataset is an important and frequent activity of any IT professional and researcher and is necessary for various use-cases. It encompasses a vast array of methods to examine datasets and produce metadata. Among the simpler results are statistics, such as the number of null values and distinct values in a column, its data type, or the most frequent patterns of its data values. Metadata that are more difficult to compute involve multiple columns, namely correlations, unique column combinations, functional dependencies, and inclusion dependencies. Further techniques detect conditional properties of the dataset at hand. This survey provides a classification of data profiling tasks and comprehensively reviews the state of the art for each class. In addition, we review data profiling tools and systems from research and industry. We conclude with an outlook on the future of data profiling beyond traditional profiling tasks and beyond relational databases
Completeness of Information Sources
Information quality plays a crucial role in every application that integrates data from autonomous sources. However, information quality is hard to measure and complex to consider for the tasks of information integration, even if the integrating sources cooperate. We present a systematic and formal approach to the measurement of information quality and the combination of such measurements for information integration. Our approach is based on a value model that incorporates both extensional value (coverage) and intensional value (density) of information. For both aspects we provide merge functions for adequately scoring integrated results. Also, we combine the two criteria to an overall completeness criterion that formalizes the intuitive notion of completeness of query results. This completeness measure is a valuable tool to assess source size and to predict result sizes of queries in integrated information systems. We propose this measure as an important step towards the usage of information quality for source selection, query planning, query optimization, and quality feedback to users.Peer Reviewe
Parcel3D: Shape Reconstruction from Single RGB Images for Applications in Transportation Logistics
We focus on enabling damage and tampering detection in logistics and tackle
the problem of 3D shape reconstruction of potentially damaged parcels. As input
we utilize single RGB images, which corresponds to use-cases where only simple
handheld devices are available, e.g. for postmen during delivery or clients on
delivery. We present a novel synthetic dataset, named Parcel3D, that is based
on the Google Scanned Objects (GSO) dataset and consists of more than 13,000
images of parcels with full 3D annotations. The dataset contains intact, i.e.
cuboid-shaped, parcels and damaged parcels, which were generated in
simulations. We work towards detecting mishandling of parcels by presenting a
novel architecture called CubeRefine R-CNN, which combines estimating a 3D
bounding box with an iterative mesh refinement. We benchmark our approach on
Parcel3D and an existing dataset of cuboid-shaped parcels in real-world
scenarios. Our results show, that while training on Parcel3D enables transfer
to the real world, enabling reliable deployment in real-world scenarios is
still challenging. CubeRefine R-CNN yields competitive performance in terms of
Mesh AP and is the only model that directly enables deformation assessment by
3D mesh comparison and tampering detection by comparing viewpoint invariant
parcel side surface representations. Dataset and code are available at
https://a-nau.github.io/parcel3d.Comment: Accepted at CVPR workshop on Vision-based InduStrial InspectiON
(VISION) 2023, see
https://vision-based-industrial-inspection.github.io/cvpr-2023
Entity Resolution On-Demand for Querying Dirty Datasets
Entity Resolution (ER) is the process of identifying and merging records that refer to the same real-world entity. ER is usually applied as an expensive cleaning step on the entire data before consuming it, yet the relevance of cleaned entities ultimately depends on the user’s specific application, which may only require a small portion of the entities. We introduce BrewER, a framework designed to evaluate SQL SP queries on unclean data while progressively providing results as if they were obtained from cleaned data. BrewER aims at cleaning a single entity at a time, adhering to an ORDER BY predicate, thus it inherently supports top-k queries and stop-and-resume execution. This approach can save a significant amount of resources for various applications. BrewER has been implemented as an open-source Python library and can be seamlessly employed with existing ER tools and algorithms. We thoroughly demonstrated its efficiency through its evaluation on four real-world datasets
Entity Resolution On-Demand
Entity Resolution (ER) aims to identify and merge records that refer to the same real-world entity. ER is typically employed as an expensive cleaning step on the entire data before consuming it. Yet, determining which entities are useful once cleaned depends solely on the user's application, which may need only a fraction of them. For instance, when dealing with Web data, we would like to be able to filter the entities of interest gathered from multiple sources without cleaning the entire, continuously-growing data. Similarly, when querying data lakes, we want to transform data on-demand and return the results in a timely manner---a fundamental requirement of ELT (Extract-Load-Transform) pipelines.
We propose BrewER, a framework to evaluate SQL SP queries on dirty data while progressively returning results as if they were issued on cleaned data. BrewER tries to focus the cleaning effort on one entity at a time, following an ORDER BY predicate. Thus, it inherently supports top-k and stop-and-resume execution. For a wide range of applications, a significant amount of resources can be saved. We exhaustively evaluate and show the efficacy of BrewER on four real-world datasets
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