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arXiv · 1708.02125

T-Crowd: Effective Crowdsourcing for Tabular Data

Caihua Shan·Nikos Mamoulis·Guoliang Li·Reynold Cheng·Zhipeng Huang·Yudian Zheng
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Abstract

Crowdsourcing employs human workers to solve computer-hard problems, such as data cleaning, entity resolution, and sentiment analysis. When crowdsourcing tabular data, e.g., the attribute values of an entity set, a worker's answers on the different attributes (e.g., the nationality and age of a celebrity star) are often treated independently. This assumption is not always true and can lead to suboptimal crowdsourcing performance. In this paper, we present the T-Crowd system, which takes into consideration the intricate relationships among tasks, in order to converge faster to their true values. Particularly, T-Crowd integrates each worker's answers on different attributes to effectively learn his/her trustworthiness and the true data values. The attribute relationship information is also used to guide task allocation to workers. Finally, T-Crowd seamlessly supports categorical and continuous attributes, which are the two main datatypes found in typical databases. Our extensive experiments on real and synthetic datasets show that T-Crowd outperforms state-of-the-art methods in terms of truth inference and reducing the cost of crowdsourcing.

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Caihua Shan, Nikos Mamoulis, Guoliang Li, Reynold Cheng, Zhipeng Huang, Yudian Zheng. 2017-08-07. T-Crowd: Effective Crowdsourcing for Tabular Data. https://arxiv.org/abs/1708.02125

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