Optimal experimental design in econometrics: The time series problem

Experiments in economics are expensive in terms of dollars and time. This suggests that efficient design is crucial, and that there is a need for econometricians to extend design theory to handle peculiarities of economic experimentation. This paper concerns optimal experimental design for various time series models. Examples are presented illustrating the improvement in estimation accuracy that can be obtained.     

Bootstrap methods for autocorrelation test with uncorrelated but not independent errors

By using bootstrap technique we investigate the properties of the Breusch [Breusch, T.S., 1978. Testing for autocorrelation in dynamic linear models. Australian Economic Papers 17, 334–355]–Godfrey [Godfrey, L.G., 1978. Testing for higher order serial correlation in regression equations when the regressors include lagged dependent variables. Econometrica 46, 1303–1310] autocorrelation tests in dynamic models with uncorrelated but not independent errors. In this paper we show that, under conditions when the errors are uncorrelated but not independent, even the best likelihood ratio test cannot achieve the asymptotic distribution under the null hypothesis of no autocorrelation. Standard bootstrap methods also fail to produce consistent results. To overcome this problem we applied several bootstrap testing methods for the same purpose and found the stationary bootstrap and Wild bootstrap with static model to perform adequately among the other bootstrap methods.     

U.S. demand for organic and conventional vegetables: a Bayesian censored system approach

Demand for organic and conventional vegetables is investigated using data from A.C. Nielsen’s 2006 Homescan panel. We use a Bayesian Markov chain Monte Carlo technique, along with data augmentation, to estimate a large linear approximate Almost Ideal Demand System with censored dependent variables. Demands are price elastic, and expenditure elasticities are very high for organic vegetables, whilst demands for conventional vegetables are primarily inelastic. We find a mix of gross substitution and complementarity among the vegetable products, but net substitution is the dominant pattern. Socio‐demographic characteristics also play important roles in demands. These findings can inform deliberations about marketing campaigns, nutrition education and policy interventions.     

Adjustment of US external imbalances: At what horizon?

The relative contribution of the trade and financial channels for correcting cyclical external imbalances of the US is decomposed by horizon. Valuation effects contribute for horizons up to a year, while trade flows for horizons up to 4 years.     

Financialization and the rise of atypical work

The current literature on financialization and the labour process focuses disproportionately on how corporate financialization induces the use of atypical work and largely overlooks the role of household financialization. This paper presents several mechanisms through which household debt and pension fund financialization increase the financial insecurity of employees, which, in turn, can curb their resistance to accepting such work contracts. To assess our arguments, we estimate the effects of corporate and household financialization on involuntary part-time and temporary employment, using a panel dataset of OECD economies. Our findings provide robust support that financialization increases significantly non-standard employment rates for the total workforce and women, but less for older employees.     

Size effect,methodological issues and ‘risk-to-default’: evidence from the UK stock market

The hedging effectiveness of dynamic strategies is compared with static (traditional) ones using futures contracts for the five leading currencies. The traditional hedging model assumes time invariance in the joint distribution of spot and futures price changes thus leading to a constant optimal hedge ratio (OHR). However, if this time-invariance assumption is violated, time-varying OHRs are appropriate for hedging purposes. A bivariate GARCH model is employed to estimate the joint distribution of spot and futures currency returns and the sequence of dynamic (time-varying) OHRs is constructed based upon the estimated parameters of the conditional covariance matrix. The empirical evidence strongly supports time-varying OHRs but the dynamic model provides superior out-of-sample hedging performance, compared to the static model, only for the Canadian dollar.     

The evolution of cognitive radio technology in Europe: Regulatory and standardization aspects

Cognitive radio (CR) is considered a promising technology that could provide important benefits in the telecommunication domain. In Europe, the number of research projects, standardization activities and public consultations by the European Commission and regulatory authorities testify to the growing interest in CR. The introduction of CR in the telecommunication market may require new regulations or changes to the way spectrum is licensed and the conditions under which it can be used. The concepts of CR can be applied to various operational scenarios, which are described in this paper.This paper identifies the main challenges for the deployment of CR technology in Europe, provides an overview of the activities by European regulatory and standardization bodies to address the identified challenges and describes a roadmap with potential actions to support the adoption of CR technology.     

Performance evaluation of retail banking services: Is there a trade-off between production and quality?

We propose a two-stage data envelopment analysis model to give an insight on the internal structure of the banking sector and study the important role of service quality in the production process. The first stage deals with the production performance and is related with the optimal use of resources to produce banking services, whereas the second stage deals with the service quality performance using customer-reported satisfaction and loyalty measures. This paper analyzes the efficiency and productivity of 36 branches of a single bank of Greece over the period 2016–2018. The results indicate the existence of a strong trade-off between production and service quality. Further insights of the study indicate that the branch size significantly affects the service quality and overall efficiency. Moreover, the employee assessments by the performance appraisal system of the bank are mainly associated with the service production and not with service quality. Finally, this study presents a managerial decision-making matrix and makes recommendations to help bank managers to improve the retail network performance.