Efficient profiling for estimation of query result quality

The issue of Data Quality (DQ) is of increasing importance as individuals as well as corporations are relying on multiple, often external sources of data to make decisions. Data quality profiles consist of statistical measurements about the quality of data sets. Query systems can use DQ profiles as a form of metadata to estimate the quality of a query result set. Traditional DQ profiling provides an estimate on the overall quality of a data set or data source, but quality of a query result can be remarkably different from the overall quality of the data set because conditions within the query typically select a subset of the data. In this paper we propose an efficient conditional DQ profiling method which can estimate the quality of a result set for a given query with guaranteed user definable level of accuracy