Expected exponential utility maximization of insurers with a Linear Gaussian stochastic factor model

In this paper, we consider the problem of optimal investment by an insurer. The wealth of the insurer is described by a Cramér–Lundberg process. The insurer invests in a market consisting of a bank account and m risky assets. The mean returns and volatilities of the risky assets depend linearly on economic factors that are formulated as the solutions of linear stochastic differential equations. Moreover, the insurer preferences are exponential. With this setting, a Hamilton–Jacobi–Bellman equation that is derived via a dynamic programming approach has an explicit solution found by solving the matrix Riccati equation. Hence, the optimal strategy can be constructed explicitly. Finally, we present some numerical results related to the value function and the ruin probability using the optimal strategy.     

Is Downward Wage Flexibility the Primary Factor of Japan's Prolonged Deflation?

By using both macro‐ and micro‐level data, this paper investigates how wages and prices evolved during Japan's lost two decades. We find that downward nominal wage rigidity was present in Japan until the late 1990s, but disappeared after 1998 as annual wages became downwardly flexible. Moreover, nominal wage flexibility may have contributed to Japan's relatively low unemployment rates. Although macro‐level movements in nominal wages and prices seemed to be synchronized, such synchronicity is not observed at the industry level. Therefore, wage deflation does not seem to be a primary factor of Japan's prolonged deflation.     

Subsidy competition and imperfect labor markets

This study presents a two‐country model of subsidy competition for manufacturing firms under labor market imperfections. Because subsidies affect the distribution of firms, subsidies influence unemployment rates and welfare in both countries. We show that when labor market frictions are high, subsidy competition is beneficial, although subsidies under subsidy competition are inefficiently high. In the coordinated equilibrium, the supranational authority provides a subsidy to firms that equal the expected total search costs, which increases the number of firms relative to laissez‐faire and improves welfare relative to laissez‐faire and subsidy competition. Finally, we find that a rise in a country's labor market frictions raises the equilibrium subsidy rate, affects unemployment rates, and lowers welfare.     

Price distortion induced by a flawed stock market index

Despite the introduction of sophisticated stock market indices, investors often trade portfolios of the flawed indices to change their exposure to the market. In this study, we show that these transactions cause significant mispricing in individual stocks, especially during periods of significant market movement. As an influential, albeit flawed, stock index, we focus on the Nikkei 225. We find index constituents that are excessively weighted on the index, experience buying (selling) pressure when the stock market surges (falls), and experience price corrections after such periods of change. In contrast, non-constituent stocks do not experience such trading pressure.     

Estimating cellphone providers' customer equity

This paper provides insights about how customer equity estimates can help businesses monitor the competition as well as aid managers in making their marketing investment decisions, and how companies can employ their marketing investments to maximize current and future yield/returns. The article concerns itself with the current offer of cellphone providers and their main products. The research includes survey data through interviews with 302 cellphone users of Sao Paulo, Brazil. The study uses this data combined with a number of economic assumptions and a financial marketing model to create an insight in customer equity values of cellphone providers in the region. The scenario dated October 2005 is that the estimated customer equity of the service provider Vivo is, respectively, 93 and 91% larger than those of competing providers Claro and TIM. The research underlines that on average the customer equity flowing from the post-paid segment is 3.5 times larger than that of the pre-paid. In addition to these results the study provides the customer lifetime value (CLV) estimates for Claro's, TIM's and Vivo's pre- and post-paid customers and analyzes the retention and loss figures of CLV. Also a discussion follows of the implications that these values will likely have for the companies' marketing strategy.     

Characterizing belief-free review-strategy equilibrium payoffs under conditional independence

This paper proposes and studies a tractable subset of Nash equilibria, belief-free review-strategy equilibria, in repeated games with private monitoring. The payoff set of this class of equilibria is characterized in the limit as the discount factor converges to one for games where players observe statistically independent signals. As an application, we develop a simple sufficient condition for the existence of asymptotically efficient equilibria, and establish a folk theorem for N-player prisoner?s dilemma. All these results are robust to a perturbation of the signal distribution, and hence remain true even under almost-independent monitoring.     

The influence of indoor air on personal exposure to volatile organic compounds and its risk estimation

This paper summarizes the results of personal exposure monitoring and estimates the risk from exposure to 18 volatile organic compounds compared with health criteria set by the US Environmental Protection Agency. In study 1, personal exposure levels and outdoor air concentrations were compared, and in study 2, personal exposure levels and the corresponding indoor air concentrations were compared. From these studies, it was concluded that personal exposure to volatile organic compounds depended markedly on indoor air quality and that handling of compounds increased personal exposure markedly. Risk estimations indicated that chloroform in tap water, benzene from cigarette smoke and p -dichlorobenzene from household insecticide needed caution.     

Belief changes and expectation heterogeneity in buy- and sell-side professionals in the Japanese stock market

We document the determinants of the expectation heterogeneity of stock price forecasters on TOPIX. Monthly panel data collected by QUICK Corporation in the Nikkei Group via surveys is utilized in the process. We examine the determinants of expectation heterogeneity by categorizing our sample into buy-side and sell-side professionals and demonstrate that the co-existence of different types of professionals contributes to the expectation heterogeneity. We show that buy-side and the sell-side professionals, who possess different business goals, differentiate the information contents as well as their interpretations of the same information in their forecasts, contributing to the expectation heterogeneity. In addition, we investigate the interactive expectation formulation of buy-side and sell-side professionals and find that buy-side professionals incorporate the sell side's ideas regarding future stock prices into their own forecasts, but refer exclusively to their own ideas when relating foreign exchange rates to future stock prices. Meanwhile, sell-side professionals tend to utilize buy-side professionals' ideas about future prices in order to improve their research and ingratiate themselves to their clients, that is, to the buy-side professionals. We demonstrate that this interactive expectation formulation also contributes to the generation of the expectation heterogeneity.     

R&D Collaborations and Product Innovation*

This paper studies the relative impact on product innovation of research and development (R&D) collaborations with universities, suppliers, customers, and competitors. It argues that each type of R&D collaboration differs in terms of the breadth of new knowledge provided to the firm and in the ease of access of this new knowledge, resulting in a different impact on product innovation. As a result, it proposes that R&D collaborations with universities are likely to have the highest impact on product innovation, followed by R&D collaborations with suppliers, customers, and, finally, competitors. These arguments are tested on the R&D collaborations undertaken by a sample of 781 manufacturing firms during 1998–2002. The tests find that R&D collaborations with suppliers have the highest positive impact on product innovation, followed by collaborations with universities. Surprisingly, R&D collaborations with customers do not appear to affect product innovation, and collaborations with competitors appear to harm it. Moreover, the positive influence of R&D collaborations with universities and suppliers is sustained over the long‐term, but the negative influence of R&D collaborations with competitors is, fortunately, short‐lived. These findings indicate that ease of knowledge access, rather than breadth of knowledge, appears to drive the success of R&D collaborations for product innovation. R&D collaborations with suppliers or universities, which are characterized by relatively easy knowledge access, have a positive influence on product innovation, whereas R&D collaborations with customers or competitors, which are characterized by reduced ease in knowledge access, are not related or are even negatively related to product innovation. Moreover, to achieve product innovation with the help of R&D collaborations, it appears that the collaboration must first have mechanisms in place to facilitate the transfer of knowledge; once these are in place, it is better if the partner has a relatively narrow knowledge base. Thus, while R&D collaborations with both suppliers and universities are positively related to product innovation, the narrow knowledge base provided by collaborations with suppliers appears to have a larger positive impact on product innovation than the wider knowledge base provided by collaborations with universities. These arguments and findings are important and novel. The paper is one of the first to theoretically explain and empirically show that various types of collaborations have a differential influence on product innovation. It goes beyond previous literature by providing a theoretical logic for ranking the likely impact of types of collaborations on product innovation. The study also suggests to managers to carefully select the partners for their firms' R&D collaborations. Collaborations with suppliers appear to be the most promising for product innovation, followed by collaborations with universities, whereas collaborations with competitors may be detrimental to product innovation.