US Patent 7949639 Attribute segments and data table bias reduction

The present invention provides a method for updating data sources. The method may include identifying a plurality of data sources, identifying a plurality of overlapping attribute segments to use for comparing the data sources, calculating a factor as a function of each of the plurality of overlapping attribute segments, and using the factors to update a first group of values in the second data source to reduce bias. Further, at least a first data source is more accurate than a second data source.