Many optimization-based portfolio rules fail to beat the simple 1/N rule out-of-sample because of parameter uncertainty. In this paper we suggest a grouping strategy in which we first form groups of equally weighted stocks and then optimize over the resulting groups only. This strategy aims at...

We extract implied price densities from wheat derivative prices during the first seven months of the Ukrainian war. Differences between short- and longterm densities indicate that market expectations about the duration of the conflict changed over time. Under simplifying assumptions, we...