Reassessing Data Quality for Information Products

The quality profile of information retrieved from a database using a query is quite important in the context of managerial decision making. Parssian et al. (Parssian, A., S. Sarkar, V. S. Jacob. 2004. Assessing data quality for information products: Impact of selection, projection, and Cartesian product. Management Sci. 50(7) 967-982) propose a methodology to determine the quality profile of the result of a query from the quality profile of the source data. Although they consider an important problem, and the proposed methodology is quite useful in practice, some of their results for the selection operation are not correct in general. Here, we identify these errors and present appropriate corrections.