Costs of Extending the Noncontributory Pension Program for Elderly: The Mexican Case

Population aging coupled with high poverty rates among older persons and a lack of access to social-security benefits or traditional support systems have led governments in low and middle-income countries to introduce non-contributory pension programs for the elderly. This article reviews a non-contributory pension program introduced in Mexico in 2007 that has since expanded greatly. We use a variety of sources to estimate current and future costs of this program.     

Does the presence of independent and female directors impact firm performance? A multi-country study of board diversity

This study empirically analyzes whether gender diversity enhances boards of directors’ independence and efficiency. Using data from 3,876 public firms in 47 countries and controlling for a wide set of corporate governance mechanisms, we find that firms with more female directors have higher firm performance by market (Tobin’s Q) and accounting (return on assets) measures. The results also suggest that external independent directors do not contribute to firm performance unless the board is gender diversified. These results hold with respect to different estimation models and robustness tests. Overall, our findings provide evidence that the female directors enhance boards of directors’ effectiveness. Finally, we find that firms that are concerned with board independence, and that firms in more complex environments are more likely to have gender-balanced boards.     

Statistical theory of shape under elliptical models via QR decomposition

The statistical shape theory via QR decomposition and based on Gaussian and isotropic models is extended in this paper to the families of non-isotropic elliptical distributions. The new shape distributions are easily computable and then the inference procedure can be studied with the resulting exact densities. An application in Biology is studied under two Kotz models, the best distribution (non-Gaussian) is selected by using a modified Bayesian information criterion (BIC)*.     

Manufacturing feature-based cost management system: a case study in Brazil

Feature costing is a topic of recent discussion related to cost management systems (CMSs) aimed at understanding how product features influence production process costs. It raises as a key issue in mass customisation environments where a single product model can present hundreds of menu options. In this study, we explore the concept of feature costing beyond the use of activity-based costing (ABC). We propose a CMS based on features and common elements as costing objects instead of products. In our model, we use the unit of production effort method to organise the direct manufacturing costs, ABC method to address the indirect cost and the standard methods to compute raw materials costs. We illustrate the method in the production of bus seats in a Brazilian manufacturing company. This study gives different perspectives to the international academic community on the use of a different CMS used by many Brazilian companies.     

Skew-normal distribution for growth curve models in presence of a heteroscedasticity structure

In general, growth models are adjusted under the assumptions that the error terms are homoscedastic and normally distributed. However, these assumptions are often not verified in practice. In this work we propose four growth models (Morgan–Mercer–Flodin, von Bertalanffy, Gompertz, and Richards) considering different distributions (normal, skew-normal) for the error terms and three different covariance structures. Maximum likelihood estimation procedure is addressed. A simulation study is performed in order to verify the appropriateness of the proposed growth curve models. The methodology is also illustrated on a real dataset.     

The Power Series Cure Rate Model: An Application to a Cutaneous Melanoma Data

In this article we propose a new cure rate survival model. In our approach the number of competing causes of the event of interest is assumed to follow an exponential discrete power series distribution. An advantage of our model is that it is very flexible, including several particular cases, such as, Bernoulli, geometric, Poisson, etc. Moreover, we derive the appropriate matrices for assessing local influence on the parameter estimates under different perturbation schemes and present some ways to perform global influence analysis. Distribution fitting can be tested for the best fitting in a straightforward way. Maximum likelihood estimation is discussed. Our proposed model is illustrated through cutaneous melanoma data.     

Learning the Wealth of Nations

We study the evolution of market‐oriented policies over time and across countries. We consider a model in which own and neighbors' past experiences influence policy choices through their effect on policymakers' beliefs. We estimate the model using a large panel of countries and find that it fits a large fraction of the policy choices observed in the postwar data, including the slow adoption of liberal policies. Our model also predicts that there would be reversals to state intervention if nowadays the world was hit by a shock of the size of the Great Depression.