In the early 50's, Markowitz introduced the modern portfolio selection theory which, to this very day, constitutes the basis of many investment decisions. Given different correlated assets, how does an investor create a portfolio maximizing the expected utility? Markowitz's contribution was to...

English Abstract: We document increased old-age mortality rates among Swedish twin mothers compared to non-twin mothers. Results are based on administrative data on mortality for the years 1990 to 2010. We argue that twins are an unplanned shock to fertility in the cohorts of older women...