An evolutionary Cournot oligopoly model with imitators and perfect foresight best responders

We consider the competition among quantity setting players in a linear evolutionary environment. To set their outputs, players adopt, alternatively, the best response rule having perfect foresight or an imitative rule. Players are allowed to change their behavior through an evolutionary mechanism according to which the rule with better performance will attract more followers. The relevant stationary state of the model describes a scenario where players produce at the Cournot‐Nash level. Due to the presence of imitative behavior, we find that the number of players and implementation costs, needed to the best response exploitation, have an ambiguous role in determining the stability properties of the equilibrium and double stability thresholds can be observed. Differently, the role of the intensity of choice, representing the evolutionary propensity to switch to the most profitable rule, has a destabilizing role, in line with the common occurrence in evolutionary models. The global analysis of the model reveals that increasing values of the intensity of choice parameter determine increasing dynamic complexities for the internal attractor representing a population where both decision mechanisms coexist.     

Nonlinearities in the real exchange rates: new evidence from developed and developing countries

This paper investigates nonlinearities in the dynamics of real exchange rates. We use Monte Carlo simulations to establish the size properties of the Teräsvirta-Anderson test, when the dynamics of the real exchange rate is influenced by an exogenous process. In addition, we show that a modified nonlinearity test, which includes additional right-hand-side variables, performs much better than the original in both Monte Carlo exercises and in the actual data on 1431 bilateral real exchange rate series. Finally, we investigate the dynamics of the real exchange rate for both developed and developing countries using the modified test for the recent floating period. In general, the results find a greater incidence of nonlinear dynamics for developing country real exchange rates.     

Forecasting value‐at‐risk in oil prices in the presence of volatility shifts

Recent evidence suggests shifts (structural breaks) in the volatility of returns causes non‐normality by significantly increasing kurtosis. In this paper, we endogenously detect significant shifts in the volatility of oil prices and incorporate this information to estimate Value‐at‐Risk (VaR) to accurately forecast large declines in oil prices. Our out‐of‐sample performance results indicate that the model, which incorporates both time varying volatility (without making any distributional assumptions) and shifts in volatility, produces more accurate VaR forecasts than several benchmark methods. We make a timely contribution as the recent more frequent occurrences of unexpected large oil price declines has gained significant attention because of its substantial impact on the financial markets and the global economy.     

Self serving reference points in double auctions

We present a novel approach for modelling self serving bias by way of reference dependence. Bias is modelled as a systematic individual level deviation of the endogenous reference point from the expected price of a good in a two person k-double auction. We find that bias decreases the efficiency of the model, and that efficiency is decreasing in both the level of bias and reference dependence.     

Accident risk analysis based on motorway exposure: an application of benchmarking technique for human safety

Abstract

Accident risk analysis for human safety and infrastructural improvement are key requirements of the engineering sector. The purpose of this paper is to identify and prioritize problematic segments of roads based upon the risk evaluation concept and to focus on the severity of accidents regarding human life loss and easy manoeuvring. This study includes the concept of considering road segments as decision-making units for application of data envelopment analysis (DEA) technique which has no compulsion of the distribution function and critical assumptions, unlike the multiple regression models. According to the proposed methodology, a section of Motorway (M-2) Lahore-Islamabad has been analyzed. Out of 200 segments under consideration, 99 segments were selected with at least one accident and one injury or fatality. Furthermore, for risk calculation and ranking of road segments, the DEA technique along with the cross-risk matrix method was applied. This optimization technique could not only be helpful in ranking but also technical decision-making and prioritizations for safety improvement, policymaking and budget allocation.     

Developing a Website Service Quality Scale: A Confirmatory Factor Analytic Approach

The surge in online consumers and their preference to buy over the Internet is nudging marketers to embrace e-commerce, but mere online presence without distinct user experience may not help attract and retain customers. Research suggests that website service quality is a determining factor in Internet buyer behavior. Several measurement tools have been used in the context of developed economies to measure e-service quality. The very few empirical researches in emerging economies, including India, motivated the researchers in the present study to refine the WEBQUAL 4.0 scale developed by Barnes and Vidgen (2002 Barnes, S. J., and R. T. Vidgen. 2002. An integrative approach to the assessment of e-commerce quality. Journal of Electronic Commerce Research 3 (3):114–27. [Google Scholar]) to measure the service quality at shopping websites. The present study employs tools like SPSS 20.0 and AMOSS 20.0 to analyze the data through exploratory factor analysis and confirmatory factor analysis. Study results suggest a 14-item WEBQUAL four factor (Ease of Use, Information Quality, Reliability, and Empathy) scale that is appropriate for Indian settings.     

Driving restrictions that work? Quito's Pico y Placa Program

Programs to reduce traffic congestion and air pollution by restricting use of motor vehicles on working days have generally not met with success, given existing studies of such programs. We conduct the first study of Quito, Ecuador's four‐year‐old Pico y Placa program and find that it has reduced ambient concentrations of carbon monoxide (CO), a pollutant primarily emitted by vehicles, by 9% to 11% during peak traffic hours. Given that ambient concentrations of CO generally track the spatial and temporal distributions of traffic, these reductions in pollution suggest similar reductions in vehicle flows. We find no significant evidence that traffic has shifted to other times of the day or week, or to other locations.     

Public Revenue‐Expenditure Nexus in South Africa: Are there Asymmetries?

This paper re‐examines the government revenue and expenditure relationship in South Africa using Enders and Siklos' Threshold adjustment and Granger causality tests. The paper allows for structural breaks in the unit root and cointegration tests. The results indicate the absence of any asymmetries in both the threshold autoregression and momentum threshold autoregression specifications of adjustments in the South African's budgeting process. The estimated symmetric error‐correction models provide support for the fiscal synchronization hypothesis of government revenues and expenditures for long‐run and short‐run dynamic equilibrium. These findings indicate that the South African fiscal authorities should try to maintain or even improve the control of their fiscal policy instruments to sustain the prudent budgetary process.     

Estimation of the mean of the selected population under asymmetric loss function

This paper is concerned with the comparison of seven estimators of the mean of the selected population from two normal populations with unknown means and common known variance under an asymmetric loss namely the LINEX loss function. The proposed estimators are invariant under location transformation. The bias and risks of the seven estimators are computed and compared. The conclusion recommend the use of δ_P (σ) which is simple to use and it is minimax. Received: January 1999