Extended weak convergence and utility maximisation with proportional transaction costs

Finance and Stochastics - In this paper, we study utility maximisation with proportional transaction costs. Assuming extended weak convergence of the underlying processes, we prove the convergence...     

Mortality Measurement at Advanced Ages: A Study of the Social Security Administration Death Master File

Accurate estimates of mortality at advanced ages are essential to improving forecasts of mortality and the population size of the oldest old age group. However, estimation of hazard rates at extremely old ages poses serious challenges to researchers: (1) The observed mortality deceleration may be at least partially an artifact of mixing different birth cohorts with different mortality (heterogeneity effect); (2) standard assumptions of hazard rate estimates may be invalid when risk of death is extremely high at old ages and (3) ages of very old people may be exaggerated. One way of obtaining estimates of mortality at extreme ages is to pool together international records of persons surviving to extreme ages with subsequent efforts of strict age validation. This approach helps researchers to resolve the third of the above-mentioned problems but does not resolve the first two problems because of inevitable data heterogeneity when data for people belonging to different birth cohorts and countries are pooled together. In this paper we propose an alternative approach, which gives an opportunity to resolve the first two problems by compiling data for more homogeneous single-year birth cohorts with hazard rates measured at narrow (monthly) age intervals. Possible ways of resolving the third problem of hazard rate estimation are elaborated. This approach is based on data from the Social Security Administration Death Master File (DMF). Some birth cohorts covered by DMF could be studied by the method of extinct generations. Availability of month of birth and month of death information provides a unique opportunity to obtain hazard rate estimates for every month of age. Study of several single-year extinct birth cohorts shows that mortality trajectory at advanced ages follows the Gompertz law up to the ages 102-105 years without a noticeable deceleration. Earlier reports of mortality deceleration (deviation of mortality from the Gompertz law) at ages below 100 appear to be artifacts of mixing together several birth cohorts with different mortality levels and using cross-sectional instead of cohort data. Age exaggeration and crude assumptions applied to mortality estimates at advanced ages may also contribute to mortality underestimation at very advanced ages.     

Defence Industry Transformation in Russia: Evidence from a Longitudinal Survey

The article is devoted to the new phenomena in the market transformation of the Russian defence-industrial complex. Based on the data generated by the repeated survey of the CEOs (general directors) of defence enterprises in 1995‐99, it examines economic performance of enterprises, their conflicts with the government and efforts at internal restructuring brought about by reductions of Russia's defence spending, mass privatisation and opening up of the domestic market. We found that despite the dramatic reduction in defence orders, inconsistent government policies and extremely unfavourable macroeconomic environment, the Russian defence industry has made significant progress in its adjustment to the market. Even before the devaluation of the ruble in the autumn of 1998 economic performance of defence enterprises had been gradually improving; it entered a virtual boom since then. Contrary to widely held views, the painful experience of the 1990s has not made the top managers of the defence industry more hostile to reforms: at the end of the decade they were generally more supportive of the market than in 1995.     

Efficiency and the trading system: The case of SETSmm

This paper studies the impact that a change from a dealer system to a market-maker supported auction system has on market quality. We study the impact that the introduction of SETSmm at the London Stock Exchange had on firm value, price efficiency and liquidity. We discover a small SETSmm return premium associated with the announcement that securities are to migrate to the new trading system. Moreover, securities that migrate to SETSmm are characterized by improvements to liquidity and pricing efficiency. We find that these changes are related to the return premium.     

Transversals, systems of distinct representatives, mechanism design, and matching

A transversal generated by a system of distinct representatives (SDR) for a collection of sets consists of an element from each set (its representative) such that the representative uniquely identifies the set it belongs to. Theorem 1 gives a necessary and sufficient condition that an arbitrary collection, finite or infinite, of sets, finite or infinite, have an SDR. The proof is direct, short. A Corollary to Theorem 1 shows explicitly the application to matching problems. In the context of designing decentralized economic mechanisms, it turned out to be important to know when one can construct an SDR for a collection of sets that cover the parameter space characterizing a finite number of economic agents. The condition of Theorem 1 is readily verifiable in that economic context. Theorems 2–5 give different characterizations of situations in which the collection of sets is a partition. This is of interest because partitions have special properties of informational efficiency.     

Economic trends 1996/97: Slow recovery in the western industrialised countries

Economic trends 1996/97: Slow recovery in the western industrialised countries     

Using semantic fingerprinting in finance

Researchers in finance and adjacent fields have increasingly been working with textual data, a common challenge being analysing the content of a text. Traditionally, this task has been approached through labour- and computation-intensive work with lists of words. In this article we compare word list analysis with an easy-to-implement and computationally efficient alternative called semantic fingerprinting. Using the prediction of stock return correlations as an illustration, we show semantic fingerprinting to produce superior results. We argue that semantic fingerprinting significantly reduces the barrier to entry for research involving textual content analysis, and we provide guidance on implementing this technique.     

Inter-temporal inventory competition and the effects of capacity constraints

This paper addresses an intertemporal inventory competition between a supplier (a provider, manufacturer) and a retailer engaged in a supply chain. The paper's focus is on the effect of capacity constraints on both parties when demands are seasonal. The paper provides a comparative study of two solution approaches, one is based on supply chain competition and the other is based on system wide optimization. Our results demonstrate that with dynamic inventory competition, the retailer reduces inventory costs by reducing the response period to higher demands while increasing the supply requests compared to the system-wide optimal approach. As a result, the supplier's inventory costs increase. An example illustrating these particular facets of the problem and its application is presented and discussed in light of the supplier and the retailer coordinating policies.     

Second-Hand Markets and Intrasupply Chain Competition

We consider a monopolistic supply chain consisting of a manufacturer and a retailer (service provider) who in addition to selling new durables, buy and resell used ones. The supply chain provides services for both new and used goods. Accordingly, consumers incur service charges for all types of goods. This study is motivated by the modern trend in cell phone businesses where retailers commence buying used phones from customers willing to upgrade their phones. The used phones are then refurbished and resold along with the services. The question that this trend gives rise to is how the interaction with the secondary market affects the performance of the supply chain in terms of its intracompetition and thereby its profit. We show that for a wide range of service rates, the second-hand market coordinates the supply chain by either reducing the double marginalization effect or by offsetting it with extra profits gained by servicing the used goods. This, however, does not imply that both parties always improve their profits. Furthermore, we find that when the service rates are low, the supply chain would be better off if the goods were not durable thereby precluding the very existence of the second-hand market.