Do Cooperatives with Better Economic–Financial Indicators also have Better Socioeconomic Performance?

VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - The overall performance of cooperatives is related to economic–financial results and actions focused on benefits for...     

The resilient frugivorous fauna of an urban forest fragment and its potential role in vegetation enrichment

Urban Ecosystems - Anthropocentric defaunation affects critical ecological processes, such as seed dispersal, putting ecosystems and biomes at risk, and leading to habitat impoverishment. Diverse...     

Three Bartlett-type corrections for score statistics in symmetric nonlinear regression models

We present simple matrix formulae for corrected score statistics in symmetric nonlinear regression models. The corrected score statistics follow more closely a χ ² distribution than the classical score statistic. Our simulation results indicate that the corrected score tests display smaller size distortions than the original score test. We also compare the sizes and the powers of the corrected score tests with bootstrap-based score tests.     

A sequential approach to testing seasonal unit roots in high frequency data

In this paper we introduce a sequential seasonal unit root testing approach which explicitly addresses its application to high frequency data. The main idea is to see which unit roots at higher frequency data can also be found in temporally aggregated data. We illustrate our procedure to the analysis of monthly data, and we find, upon analysing the aggregated quarterly data, that a smaller amount of test statistics can sometimes be considered. Monte Carlo simulation and empirical illustrations emphasize the practical relevance of our method.     

Bayesian inverse problems with heterogeneous variance

We consider inverse problems in Hilbert spaces under correlated Gaussian noise, and use a Bayesian approach to find their regularized solution. We focus on mildly ill-posed inverse problems with fractional noise, using a novel wavelet-based vaguelette–vaguelette approach. It allows us to apply sequence space methods without assuming that all operators are simultaneously diagonalizable. The results are proved for more general bases and covariance operators. Our primary aim is to study posterior contraction rate in such inverse problems over Sobolev classes and compare it to the derived minimax rate. Secondly, we study effect of plugging in a consistent estimator of variances in sequence space on the posterior contraction rate. This result is applied to the problem with error in forward operator. Thirdly, we show that empirical Bayes posterior distribution with a plugged-in maximum marginal likelihood estimator of the prior scale contracts at the optimal rate, adaptively, in the minimax sense.     

A Task-Based Indicator for Labour Market Mismatch

This article uses a task-based approach to measure labour market mismatch and to study the wage effects of mismatch. We propose a new indicator—cognitive mismatch—and contrast it with the commonly used overqualification indicator. We argue that considering the tasks performed in each occupation captures more adequately the complexity of job requirements and tackles the major drawbacks of the existing approaches measuring mismatch. Using rich administrative data from the German Sample of Integrated Labour Market Biographies, we find that 4.8% of the total employment episodes are matched in terms of qualification but mismatched in terms of the tasks performed. Fixed Effects models show that the largest wage loss occurs in cases of mismatch in both education level and tasks performed at work. We conclude that each indicator is capturing different facets of mismatch and that they should be used complementarily in labour market mismatch analyses.

     

Cognitive-ergonomics and instructional aspects of e-learning courses

This paper presents an analysis of cognitive-ergonomic aspects of e-learning courses, offered by an organism from Brazilian Public Administration. The Cognitive Ergonomic studies conductive and cognitive aspects concerning to the relation between human, physics elements and social elements of the work space. From that usability aspects were evaluated by these points: i) visualization; ii) text comprehension lecture; iii) memory; iv) interface; v) instructional design; and vi) attention and learning. That survey is characterized as having been applied using the following techniques: (1) bibliographic survey, (2) field survey and (3) analysis of the documents. It was chosen the semi-structured questionnaire as the main method of data collection. About the interacting with artifacts, the interface of the courses is classified as direct engagement, because it allows the user to get the feeling that acts directly on the objects. Although the courses are well-structured they have flaws that will be discussed below. Even with these problems, the courses have a good degree of usability.