We propose a multi-stage stochastic trading cost model in optimal portfolio selection. This strategy captures uncertainty in implicit transaction costs incurred by an investor during initial trading and in subsequent rebalancing of the portfolio. We assume that implicit costs are stochastic as...

As in continuous time, the nontrading region (NTR) in a mean-variance model with fixed, proportional, and quadratic trading costs is a singleton only for pure quadratic costs. Utility loss from costs is approximately proportional at small cost levels, and approximately constant at large cost...

We remove the technical assumption $\gamma>0$ imposed by Dai et. al. who consider the optimal investment and consumption decision of a CRRA investor facing proportional transaction costs and finite time horizon. As a by-product, we obtain an estimate on the optimal consumption

We give a simple explicit formula for turnover reduction when a large number of alphas are traded on the same execution platform and trades are crossed internally. We model turnover reduction via alpha correlations. Then, for a large number of alphas, turnover reduction is related to the largest...

We study optimal investment with multiple assets in the presence of small proportional transaction costs. Rather than computing an asymptotically optimal no-trade region, we optimize over suitable trading frequencies. We derive explicit formulas for these and the associated welfare losses due to...

In this paper we investigate sources and characteristics of value, size and momentum profits on the Polish stock market. The research aims to broaden the academic knowledge in a few ways. First, we deliver fresh out-of-sample evidence on value, momentum, and size premiums. Second, we analyzemthe...