“…The means, variances and correlations of asset returns are usually estimated by their historical values, or their transformations. But the performance of portfolio models with inputs estimated in this way has been disappointing due to large estimation errors (Benati, 2015;Dhingra, 1983;Hui, et al, 1993;Levy and Simaan, 2016;Maillet, et al, 2015). In recent years a new approach to estimating portfolio inputs has been developed which recognises that asset returns are not generated by a single economic regime (Levy and Kaplanski, 2015;Bae, et al, 2014).…”