Optimization in machine learning typically deals with the minimization of empirical objectives defined by training data. The ultimate goal of learning, however, is to minimize the error on future data (test error), for which the training data provides only partial information. In this view, the...

The fixed effects (FE) panel model is one of the main econometric tools in empirical economic research. A major practical limitation is that the parameters on time-constant covariates are not identifiable. This paper presents a new approach to grouping FE in the linear panel model to reduce...

Income is an important economic indicator to measure living standards and individual well-being. In Germany, there exist different data sources that yield ambiguous evidence when analysing the income distribution. The Tax Statistics (TS) - an income register recording the total population of...

Income is an important economic indicator to measure living standards and individual well-being. In Germany, there exist different data sources that yield ambiguous evidence when analysing the income distribution. The Tax Statistics (TS) - an income register recording the total population of...

The fixed effects (FE) panel model is one of the main econometric tools in empirical economic research. A major practical limitation is that the parameters on time-constant covariates are not identifiable. This paper presents a new approach to grouping FE in the linear panel model to reduce...