A Visual Technique to Assess the Quality of Datasets - Understanding the Structure and Detecting Errors and Missing Values in Open Data CSV Files

Abstract

Nowadays, more and more information is flowing in and is provided on the Web. Large datasets are made available covering many fields and sectors. Open Data (OD) plays an important role in this field. Thanks to the volumes and the variety of the released datasets, OD brings high societal and business potential. In order to realize this potential, the reuse of the datasets (e.g. in internal business processes) becomes primordial. However, if the aim is to reuse OD, it is also necessary to be able of assessing its quality. This paper demonstrates how Information Visualization may help on this task and presents Stacktab chart-a new chart to analyse and assess CSV files in order to understand their structure, identify the location of relevant information and detect possible problems in the datasets.