Asymptotic solutions of diffusion models for risk reserves.
A discrete time model of financial market is considered. In the focus of attention is the guaranteed profit of the investor which arises when the jumps of the stock price are bounded. The limit distribution of the profit as the model becomes closer to the classic model of geometrical Brownian motion is established. It is of interest that the approximating continuous time model does not assume any such profit.
We study the asymptotical behaviour of expected utility from terminal wealth on a market in which asset prices depend on economic factors that are unobserved or observed with delay.
The paper analyzes auctions which are not completely enforceable. In such auctions, economic agents may fail to carry out their obligations, and parties involved cannot rely on external enforcement or control mechanisms for backing up a transaction. We propose two mechanisms that make bidders directly or indirectly reveal their trustworthiness. The first mechanism is based on discriminating bidding schedules that separate trustworthy from untrustworthy bidders. The second mechanism is a generalization of...
V textu představíme tzv. Banzhafův index, který umožňuje kvantifikovat sílu voliče v předepsaném hlasovacím systému. Definice indexu je zcela elementární, podrobnější zkoumání jeho vlastností však vede k zajímavé a hlubší matematice. Výklad je ilustrován řadou konkrétních příkladů ze světa politiky; uvidíme, že díky Banzhafovu indexu se matematika dostala i na stránky novin.
In this work we consider a model of an insurance company where the insurer has to face a claims process which follows a Compound Poisson process with finite exponential moments. The insurer is allowed to invest in a bank account and in a risky asset described by Geometric Brownian motion with stochastic volatility that depends on an external factor modelled as a diffusion process. By using exponential martingale techniques we obtain upper and lower...