The social diversification of fashion

We propose a model to investigate the dynamics of fashion traits purely driven by social interactions. We assume that people adapt their style to maximize social success, and we describe the interaction as a repeated group game in which the payoffs reflect the social norms dictated by fashion. On one hand, the tendency to imitate the trendy stereotypes opposed to the tendency to diverge from them to proclaim identity; on the other hand, the exploitation of sex appeal for dating success opposed to the moral principles of the society. These opposing forces promote diversity in fashion traits, as predicted by the modeling framework of adaptive dynamics. Our results link the so-called horizontal dynamics—the primary driver of fashion evolution, compared with the vertical dynamics accounting for interclass and economic drivers—to style variety

United States Pension Benefit Plan Design Innovation: Labor Unions as Agents of Change

Labor unions played an historic role creating the occupational pension system in the private and public sectors in the post-World War II era. That system, which was dominated by defined benefit pension plans, is in decline. The transition to a new system is economically and socially painful, and has been accelerated by two financial crises in the past decade. This paper uses a case study of a private sector union to demonstrate how labor unions can influence the renegotiation of the pension contract for American workers. The case study describes how one union evaluated the pension crisis from a sustainability viewpoint, and responded pro-actively by developing a hybrid pension plan that attempted to align the interests of all stakeholders through equitable risk sharing. The hybrid plan developed by this union eventually had a broader influence on the pension community at large and the public policy debate around the pension crisis

The Interest Rate Deregulation and Bank Lending in Nigeria

This study examined the interest rate deregulation and bank lending in Nigeria within the period of 1987 to 2011. The study was carried out to show the relevance of the hinges on the fact that credit and its costs (interest) perform a private role in shaping the economic future of Nigeria. The ordinary least square (OLS) techniques were utilized to estimate the parameters of the modeled independent variables/regressors on our chosen dependent variable. The hypothesis that the interest rate deregulation has a significance impact on bank lending was tested and validated with the result. Our findings gave rise to statistically significant t-statistics, which confirms the effects of the independent variables on the dependent variables. Some of the recommendations to further accelerate growth of the banking sector are more efforts to recommend that government through central bank should implement stringent fiscal and monetary policies aimed at reducing inflation. Others include that banks have been over-reacting to interest measures by increasing the rates to unprofitable levels especially during the period of deregulation. Keywords: Interest rate, deregulation, bank lendin

Common Inaccuracies in Fertility Parameters of Matrix Population Models and Suggestions for Corrections

Matrix population models are often applied to a variety of organisms possessing different life history traits, and fertility rates need to be estimated differently for them. Although there is a general method described for estimating fertility rates, there is a substantial variability in the ways fertility rates are estimated. The objective of this study was to evaluate the clarity and accuracy in estimating fertility parameters for their use in matrix population models with the intention of developing a transparent guide that would assist in overcoming the most frequent errors. The study involves a meta-analysis of published articles that constructed a matrix population model for organisms within the Kingdom Animalia. Literature is organized into different animal group categories including, invertebrates, fish, birds, reptiles, and large mammals. Within each category each individual study is categorized based on whether it included sufficient information about estimating fertility rates and if the methods used for parameters were correct. In addition, results are compared with the corresponding life history traits of the organisms. Results indicate mistakes in estimating fertility occurred more frequently due to the omission of survival rate into the fertility coefficient and mistakes were also seen higher among opportunistic strategists and birth-pulse structured models. Of the studies sampled, mistakes in estimating fertility did not decrease over the ten year study period. These results suggests that perhaps mistakes continue to be present as a result of the entanglement between fecundity and fertility that has remained throughout literature. A descriptive set of methods are developed to address the common mistakes found in the literature review. However, further development of tools to assist ecologists in applying matrix population models are needed

Science in Sanitary and Phytosanitary Dispute Resolution

The World Trade Organization Sanitary and Phytosanitary Agreement (SPS Agreement) relies heavily on science and expert organizations to avoid and resolve trade disputes over measures enacted under the rationale of food safety or plant and animal health protection. However, the state of science for sanitary and phytosanitary risk analysis is highly uncertain, and the SPS Agreement leaves many science policy issues unsettled. The international agencies charged under the SPS Agreement with harmonizing standards and forging international scientific consensus face a daunting and politically-charged task. Two case studies are briefly developed. In the first case, the international scientific consensus strongly supports the U.S. challenge of the European Union’s ban on cattle growth hormones, but the root causes of the dispute go much deeper. The case suggests that establishing a precedent for SPS measures based solely on "sound science" may be a slippery objective. In the second case, domestic avocado producers challenged a U.S. Department of Agriculture assessment which concluded that a partial lifting of the ban on Mexican avocado imports posed a negligible plant pest risk. Although the Department’s phytosanitary risk assessment gained endorsement by independent scientists, a contributing factor to resolving this dispute was the threat of retaliation against U.S. agricultural exports to Mexico. A recent survey of current and proposed technical barriers to U.S. agricultural exports suggests that the trade impacts could approach $5 billion a year and that the most common SPS disputes in the future will be over biological hazards�particularly plant pests and food-borne microbial pathogens. This poses a tremendous challenge, however, because the practice of risk assessment for biological stressors is much less developed than that for chemical substances. The paper concludes with some proposed criteria for evaluating the weight of scientific evidence in SPS risk assessment.

Cascading Effects of Fuel Network Interdiction

This thesis develops the Fuel Interdiction and Resulting Cascading Effects (FI&RCE) model. The study details the development and experimental testing of a framework for assessing the interdiction of a refined petroleum production and distribution network. FI&RCE uses a maximum flow mathematical programming formulation that models the transit of fuels from points of importation and refinement through a polyduct distribution network for delivery across a range of end user locations. The automated model accommodates networks of varying size and complexity. FI&RCE allows for parameters and factor settings that enable robust experimentation through implementation in MATLAB 2014 and the commercial solver CPLEX (Version 12.5). Experimental design allows the investigation of interdiction or disruption on supply and network infrastructure locations in order to support the strategic analytical needs of the user. Given a target set, FI&RCE provides measured responses for the resulting fuel availability and a valuation of economic loss. The value of economic loss feeds a Leontief based input-output model that assesses the cascading effects in the studied economy by implementing a mathematical program that optimizes the remaining industrial outputs. FI&RCE demonstrates a framework to investigate the military and cascading effects of a fuel interdiction campaign plan using a realistic case study