Deteriorating inventory model for ready-to-eat food under fuzzy environment

Decreased costs and enhanced customer satisfaction are two main objectives of SCM, and good inventory policy can achieve both simultaneously. Product perishability is a critical aspect of inventory policy. Ready-to-eat food products are very common consumer goods that are, in fact, perishable. The value the RTE food retains is, however, closely dependent on its quality. From the vendor’s point of view, quantifying quality and remaining value should be a critical business issue. In consequence, we combined the traditional deterioration model and quality prediction model to develop a new deteriorating inventory model for RTE food products. This new model quantifies food quality and remaining value. We also improved the new model by fuzzifying storage temperature to simulate temperature fluctuation. The proposed model uses real deterioration rate data. Numerical analysis is conducted in a case study. Overall, the model demonstrates that high storage temperatures reduce profits and force shorter order cycles.     

LOW PRICE, PRICE-EARNINGS RATIO, MARKET VALUE, AND ABNORMAL STOCK RETURNS

In this research, the individual and net effects of low price, low price/earnings (P/E) ratio, and small size on the risk-adjusted excess returns are investigated for the fourth quarter of 1975 to the fourth quarter of 1985. The entire sample is divided into quintiles, and the resulting portfolios are rebalanced at the end of each quarter. Low price, low P/E ratio, and small value portfolios did experience greater excess returns. By applying the experimental control technique, the net effect of stock price is significant after controlling the size. Similarly, the net effect of the market value is significant after the stock price is controlled. The net effect of the P/E ratio is insignificant after controlling either the stock price or the market value.     

Valuing the potential economic impact of climate change on the Taiwan trout

The purpose of this study is to estimate the value of the potential economic impact of climate change on the Taiwan trout (also referred to as Oncorhynchus masou formosanus), an endangered species that only lives in high mountain stream sections in which the water temperature is lower. A two-stage approach is adopted to estimate the value of the change in the Taiwan trout stock due to a change in climate. The first stage involves establishing the relationship between the Taiwan trout stock and climate change, while the second stage involves estimating the non-market value of the change in the Taiwan trout population using the double bound model associated with the contingent valuation method (CVM). Our results indicate that the total Taiwan trout population will decline from 1612 to 974, 560, and 146 if precipitation in Taiwan increases by 0.6 mm/day, while the temperature increases by 0.9 °C, 1.8 °C, and 2.7 °C, respectively. The mean willingness to pay per person per year to avoid a change in the trout stock caused by climate change is found to be US$16.22, US$25.72, and US$33.60, respectively.     

A systematic and efficient simulation scheme for the Greeks of financial derivatives

Greeks are the price sensitivities of financial derivatives and are essential for pricing, speculation, risk management, and model calibration. Although the pathwise method has been popular for calculating them, its applicability is problematic when the integrand is discontinuous. To tackle this problem, this paper defines and derives the parameter derivative of a discontinuous integrand of certain functional forms with respect to the parameter of interest. The parameter derivative is such that its integration equals the differentiation of the integration of the aforesaid discontinuous integrand with respect to that parameter. As a result, unbiased Greek formulas for a very broad class of payoff functions and models can be systematically derived. This new method is applied to the Greeks of (1) Asian options under two popular Lévy processes, i.e. Merton's jump-diffusion model and the variance-gamma process, and (2) collateralized debt obligations under the Gaussian copula model. Our Greeks outperform the finite-difference and likelihood ratio methods in terms of accuracy, variance, and computation time.     

Higher education,employment and economic growth: Exploring the interactions

ABSTRACT

This article interrogates the impact and nature of South Africa’s post-apartheid economic growth performance through the lens of human capital investment with a particular emphasis on higher education. The South African economy has been characterised by a skills-biased trajectory, ensuring jobs for the better educated. By differentiating between tertiary and vocational training, we find that further education and training (FET) graduates are almost as likely to be employed as school leavers without higher education. We analyse the extent to which the educational attainments of labour affect the nature and trajectory of economic growth in South Africa, by estimating Olley and Pakes’ two-stage regression on a modified Cobb–Douglas production function. The results indicate that the degree cohort contributes to economic growth whilst other higher education institutions, including FET colleges, do not productively contribute to economic growth.     

The Impact of Leaving Camps on Well-being of Internally Displaced Persons in Northern Uganda

The armed conflict in Northern Uganda led to a large number of internally displaced persons (IDPs). After the government announced the declaration of free movement on 30 October 2006, a large number of IDPs left camps. Transition from camp life to post-camp life has important implications for population well-being. This paper uses the Ugandan National Household Survey conducted in 2005-2006 and 2009-2010 and a difference-in-differences method to estimate changes in IDPs' well-being measured by self-reported heath as well as household food consumption. We do not find a significant effect of leaving camps on self-reported illness and household food consumption but we find a significant effect on the choice of healthcare providers utilised. The postcamp effect was estimated to increase the use of non-free health providers, an effect composed of more visits to informal providers and greater choice of formal private providers, when formal providers are utilised. Those findings shed light on policy-relevant issues in the areas of land rights, recovery of public health systems and gender inequalities in well-being.     

Learning to be Sociable: The Evolution of Homo Economicus

A bstract .   This article studies the evolution of the economic man ( Homo economicus ) from its original conception until the current day. By analyzing the discourse of economic articles, we provide a chronological account of the economic man's intellectual and philosophical development as it evolved from what we term the philosophical age to the neoclassical age and finally to the strategic age. The article then shows how the economic man in the strategic age is slowly finding convergence with the sociological man ( Homo sociologicus ). A reconciliation of the two sapiens is difficult. However, recent papers on behavioral and experimental economics provide insights into a possible reconciliation. Our study argues that the purpose of the sociological man is to identify who he is, how he interacts with people within a society, and the antecedents to such behaviors. Homo economicus, however, has no overarching philosophical assumptions on what he values. The objectives of each discipline are different and, once one is mapped onto the other, it is unclear if there is truly any tension between them.     

The role of Chinese stock market in global stock markets: A safe haven or a hedge?

The contribution of the study is threefold. First, the paper proposes a new empirically testable definition for a safe haven and a hedge from the viewpoint of extreme and regular dependences measured by a modern statistical tool of copulas. Second, this paper investigates the extreme and regular dependences between the Chinese and the G7 stock markets, using a mixture copula specification, and the results reveal that the Chinese stock market has been not only a hedge but also a safe haven for the G7 stock markets all these years. Finally, this study suggests that the Chinese stock market is the target market for global stock fund managers and international investors, who are seeking a hedge or a safe haven for their portfolios, under turbulence.