Bing Tian Dai Nick Koudas Beng Chin Ooi Divesh Srivastava Suresh Venkatasubramanian Column Heterogeneity as a Measure of Data Quality. 2006 conf/cleandb/2006 CleanDB http://pike.psu.edu/cleandb06/papers/CameraReady_111.pdf db/conf/cleandb/cleandb2006.html#DaiKOSV06