The goal of human resources analytics is to provide an organization with insights for effectively managing employees so that business goals can be reached quickly and efficiently. The challenge of human resources analytics is to identify what data should be captured and how to use the data to model and predict capabilities so the organization gets an optimal return on investment (ROI) on its human capital. Although most organizations have enough data to make analytics useful, the data is often created and stored in multiple places in multiple formats. There is no shortage of vendors who offer dedicated human resources analytics software products, but many companies simply create a custom data warehouse for HR data and leverage business intelligence (BI) applications on top. Other companies use data federation technology to aggregate data from disparate sources in a virtual database.