Exchange rate bubbles: Fundamental value estimation and rational expectations test

We propose a model of periodically collapsing bubbles which extends the Van Norden (1996) model, and nests it, by considering a non-linear specification for the bubble size in the survival regime, and the endogenous determination of the level of the fundamental value of the stochastic process. They allow us to test for rationality in the formation of expectations, and remove the arbitrariness of exogenously setting the level of the fundamental value. This general model is applied to the exchange rate of the Brazilian real to the US dollar from March 1999 to February 2011. The futures market exchange rate is used as a proxy of its expected future value, and three different structural models are considered for the determination of the fundamental value. The first two imply that the exchange rate satisfies either purchasing power parity (PPP), or a modified version of it. The third structural model is a version of the monetary model of exchange rate determination, fitted to the period under consideration. We obtain the maximum likelihood estimate of the parameters of the models, explore the properties of the errors, test its restricted versions, and compare the three specifications for the fundamental. We find that the models we propose fit well the data, and are useful in the heuristic interpretation of the exchange rate movements of the period. Finally we select the structural models that display the best performance, according to several criteria.     

Taxing Sin Goods and Subsidizing Health Care*

We study the taxation of sin goods in a two‐period, three‐good model. Individuals can buy health care to compensate for the damages caused by their earlier sin‐good consumption. Individuals are myopic and underestimate the effect of the sinful consumption on health; in their second period, they may acknowledge their mistake or persist in their error. We characterize and compare the first‐best and the (linear) second‐best taxes in these different settings. In particular, we examine how the results are affected by the way sin‐good consumption and health care interact in health production technology.     

Optimal mobile termination rate: The Brazilian mobile market case

This paper presents a study of the impacts of changes in the mobile termination rate in Brazil using 2008 as the base year. For this we use an extension of the monopolistic competition model used by Wright, Thompson, and Renard (2007) allowing for the charge of interconnection fee also from calls originating on mobile networks and differentiated prices for on-net and off-net calls. After calibration of the model parameters and estimation of the price elasticity of demand for mobile services, we conduct a comparative static analysis varying the mobile termination rate in order to find the optimal value for that parameter. Finally, we provide some discussions on policy regulation in that sector depending on the objective of the regulator agency.     

Selección de proveedores basada en análisis dimensional

This article presents the evaluation of a group of six suppliers for an electromechanical component of hydraulic bombs. The comparison is made by using the dimensional analysis technique and the attributes evaluated were the component´s costs, product quality, post sale service from supplier, product reliability, supplier’s administration and organization and production technology in their production system. In addition, in order to integrate the opinion of several persons in the selection and decision process, the information analysis was done with the aid of a decision group integrated by five persons with responsibilities in the purchase area. The technique is easy to apply and has been widely accepted by its users, who are making its use extensive to other components supplier’s selection process.     

Forced Saving,Redistribution, and Nonlinear Social Security Schemes

This paper studies the design of nonlinear social security schemes when individuals differ in productivity and in their degree of myopia. Myopic individuals may not save “enough” for their retirement. The welfare function is paternalistic: The rate of time preference of the farsighted is used for both types. We show that the solution does not necessarily imply forced savings for the myopics: Paternalistic considerations are mitigated by incentive effects. Numerical results suggest that as the proportion of myopic individuals increases, there is less redistribution and more forced saving, and the desirability of social security increases.     

Toward the crisis: a Kaleckian-Keynesian interpretation of the instability of growth and capital accumulation in Brazil

This article examines theoretically and empirically the instability of Brazilian investment and growth for the past couple of decades, highlighting the evolution that led to the current crisis. A theoretical discussion highlights the importance of Kaleckian and Keynesian approaches in understanding the semi-stagnation of the Brazilian economy since the 1990s. Empirical evidence shows that investment has increased until 2013, but not to the point of getting the economy back on the track of high growth rates and higher investment-GDP ratios. The econometric findings are compatible with the theoretical underpinnings of investment activity based on Keynes and Kalecki and suggest the existence of room for activist policies in Brazil in order to stimulate economic activity.