Changes (returns) in stock index prices and exchange rates for currencies are argued, based on empirical data, to obey a stable distribution with characteristic exponent α < 2 for short sampling intervals and a Gaussian distribution for long sampling intervals. In order to explain this phenomenon, an Ehrenfest model with large jumps (ELJ) is introduced to explain the empirical density function ...

age were examined relative to climate variability and climate change. Good correlations were also found with climatic variables such as the Pacific Decadal Oscillation, Aleutian Low Pressure Index, or water temperature alone (Peterman, MacFarlane, Brown, Schweigert, Bonk, Tarasyuk). Competition with other pelagic species was suggested as a possible mechanism explaining changes in growth of chub...

2. Approach We first define a family of very simple basic investment strategies. We wish to guarantee that the performance of our strategy is close to that of any of the the basic strategies that we may consider, which can be achieved by hedging : distributing our starting capital over all basic strategies. Let δ = δ1, δ2, . . . be a sequence of positive reals, then the basic strategy σδ initia...

Over the last decades, views on fisheries management have oscillated between alarm and trust in management progress. The predominant policy for remedying the world fishing crisis aims at maximum sustainable yield (MSY) by adjusting gear selectivity and fishing effort. Here we report a case study on how striving for higher yields from the Eastern Baltic cod stock by increasing selectivity has be...

Despite sustained interest in product alliance activity, little is known regarding the effect of product alliances on shareholder value. Whereas proponents of alliances justify their formation by emphasizing access to relevant resources and know-how, critics highlight the risks inherent in alliance partner opportunism. To reconcile these opposing viewpoints, we develop and test a conceptual fra...

This paper provides new insights into the sources of bias of the implied by option prices volatility to forecast its physical counterpart. This bias can be attributed to the volatility risk premium effects. The latter are found to depend on the high order cumulants of the risk neutral density. These cumulants capture the risk averse behavior of the investors in the stock and option markets for ...

We study the behavior of the critical price of an American put option near maturity in the exponential Lévy model when the underlying stock pays dividends at a continuous rate. In particular, we prove that, in situations where the limit of the critical price is equal to the stock price, the rate of convergence to the limit is linear if and only if the underlying Lévy process has finite variatio...

Adenovirus vectors (rAd) are widely used in gene therapy to deliver genes of interest. It is therefore essential to develop a purification process that clears the adenovirus of undesired contaminants while purifying high titre stock adenovirus. The current standard method of purification uses a CsCl density gradient, which is formed during centrifugation. The limitations of this procedure inclu...