Optimal combination of density forecasts
نویسندگان
چکیده
This paper brings together two important but hitherto largely unrelated areas of the forecasting literature, density forecasting and forecast combination. It proposes a simple data-driven approach to direct combination of density forecasts using optimal weights. These optimal weights are those weights that minimise the ‘distance’, as measured by the Kullback-Leibler Information Criterion, between the forecasted and true, but unknown, density. Comparisons with the optimal combination of point forecasts are made. An application to simple time-series density forecasts and two widely used published density forecasts for U.K. inflation, namely the Bank of England and NIESR “fan” charts, illustrates that combination can but need not always help. JEL Classification: C53; E37
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