Competition theory predicts that multispecies coexistence requires that species have traits that fall on the same interspecific trade-off surface. Fossil records for mollusks, mammals, trees, and other taxa show that with rare exception, ecologically similar species have coexisted for a million years or more after interchange between formerly isolated realms. This coexistence suggests the possi...

We investigate the risk–return trade-off on US and European stock markets. non-linear with a special eye to tails of returns using quantile regressions. first consider market portfolio. find that is significantly positive at upper tail (0.9 quantile), where large excess returns. The as expected from asset pricing models. For lower (0.1 for negative returns, negative. Additionally, median (0.5 i...

We investigate the risk-return trade-off on US and European stock markets. non-linear with a special eye to tails of returns using quantile regressions. first consider market portfolio. find that is significantly positive at upper tail (0.9 quantile), where large excess returns. The as expected from asset pricing models. For lower (0.1 for negative returns, negative. And median (0.5 insignifica...