Time-Dependent Black-Litterman

The Black-Litterman method is widely used in the investment management industry to incorporate views in investment portfolios. The method applies when views are expressed as expected returns over the horizon on which allocation decisions are made, i.e., the investment horizon. In practice, however, the investor's views are typically formulated for the near future while the investor's investment horizon is much longer. To incorporate such views, we introduce the time-dependent Black-Litterman method and show that, in this time-dependent setting, a distinction should be made between unconditional and conditional views. Furthermore, we demonstrate its use for buy and hold investors. In an example, we show that the investor's views have a plausible impact on resulting allocation decisions