Aggregation may be harmful but cannot always be avoided in the analysis of complex econometric models. It should be carried out intelligently by choosing ein aggregative model optimally for modes of aggregation speeified in advance, i.e. minimizing the bias introduced by aggregation and...

A widely used method in the analysis of complex econometric models is to replace the "true model" by an aggregative one in which the variables are grouped and replaced by sums or weighted averages of the variables in each group. The analysis of the problem of choosing an aggregative model...

Many contemporaneously aggregated variables have stochastic aggregation weights. We compare different forecasts for such variables including univariate forecasts of the aggregate, a multivariate forecast of the aggregate that uses information from the disaggregate components, a forecast which...