The present paper introduces new sign tests for testing for conditionally symmetric martingale-difference assumptions as well as for testing that conditional distributions of two (arbitrary) martingale-difference sequences are the same. Our analysis is based on the results that demonstrate that...

The recent financial crisis has revealed significant externalities and systemic risks that arise from the interconnectedness of financial intermediaries' risk portfolios. We develop a model in which the negative externality arises because intermediaries' actions to diversify that are optimal for...

We present a unified approach to value at risk analysis under heavy-tailedness using new majorization theory for linear combinations of thick-tailed random variables that we develop. Among other results, we show that the stylized fact that portfolio diversification is always preferable is...

We study multiline insurance companies with limited liability. Insurance premiums are determined by no-arbitrage principles. The results are developed under the realistic assumption that the losses created by insurer default are allocated among policyholders following an "ex post", pro rata,...

This paper studies the properties of the sex ratio in two-period models of threshold (e.g., polygenic or temperature-dependent) sex determination under heavy-tailedness in the framework of possibly skewed stable distributions and their convolutions. We show that if the initial distribution of...