Computing maximum likelihood estimates from type II doubly censored exponential data

It is well-known that, under Type II double censoring, the maximum likelihood (ML) estimators of the location and scale parameters, θ and δ, of a twoparameter exponential distribution are linear functions of the order statistics. In contrast, when θ is known, theML estimator of δ does not admit a closed form expression. It is shown, however, that theML estimator of the scale parameter exists and is unique. Moreover, it has good large-sample properties. In addition, sharp lower and upper bounds for this estimator are provided, which can serve as starting points for iterative interpolation methods such as regula falsi. Explicit expressions for the expected Fisher information and Cramér-Rao lower bound are also derived. In the Bayesian context, assuming an inverted gamma prior on δ, the uniqueness, boundedness and asymptotics of the highest posterior density estimator of δ can be deduced in a similar way. Finally, an illustrative example is included.     

Exploratory and exploitative innovation in family businesses: the moderating role of the family firm image and family involvement in top management

Review of Managerial Science - Drawing on innovation and family business literature, this study examines the largely overlooked family effect in exploratory and exploitative...     

Open innovation and quality management: the moderating role of interorganisational IT infrastructure and complementary learning styles

This study seeks to explain the influence of quality management on the relationship between open innovation and performance. We propose that, to contribute to open innovation performance, an organisation’s commitment to quality improvement must rely on the combination of its own resources and capabilities and its open innovation partners’ resources and capabilities. Specifically, we examine the moderating role of an interorganisational IT infrastructure and the complementarity of learning styles among an organisation committed to quality improvement and its supply network. Using data from 270 managers of European firms, our results show that the negative effects of quality management on open innovation performance can be overcome by complementing the organisation’s learning style with that of its open innovation partner, particularly, its supply network, and, most importantly, obtaining information technologies compatible with those of its supply network members.     

Examining coping strategies used by Spanish female social work students: evidence for the importance of social problem-solving abilities

The present study examined the role of social problem-solving abilities in the coping strategies used by 310 female social work students from Spain. Results from comparative analyses of the coping strategies, used by students to deal with stressful situations, indicated the greater use of functional forms of coping (eg problem solving and cognitive restructuring), compared to dysfunctional forms of coping (eg problem avoidance and wishful thinking). Moreover, results from regression analyses indicated that constructive social problem-solving abilities, namely, positive problem orientation and rational problem solving, predicted the use of functional coping strategies (eg problem solving, cognitive restructuring, and express emotions). Alternatively, one damaging social problem-solving ability, namely, negative problem orientation, predicted the use of dysfunctional coping strategies (eg problem avoidance, wishful thinking, self criticism, and social withdrawal). Taken together, these findings provide an important first step for understanding what and how social problem-solving abilities might inform how social work students cope with stressful situations as they arise. Some implications for social work education and training are discussed.     

Career Planning in Spain: Do Fixed-term Contracts Delay Marriage and Parenthood?

The aim of this paper is to find an empirical connection between the striking increase in the use of fixed-term contracts in Spain and the observed delay in the age at marriage and maternity. Using the eight waves of individual information from the European Household Panel for Spain, we find that for men, the decision whether to get married is strongly negatively affected by holding unstable contracts or not working, relative to when an indefinite contract is held. However, for women, results suggest that holding fixed-term contracts is not a deterrent for the decision whether to get married. With respect to the decision of whether to enter into parenthood, results indicate that for all childless women, either with no partner, holding fixed-term contracts delays entry into motherhood relative to the holding of indefinite contracts. The discouragement effect is stronger for women with no partner, though.JEL classification: D1, J1     

Semiparametric quasi-likelihood estimation with missing data

Abstract

This article develops quasi-likelihood estimation for generalized varying coefficient partially linear models when the response is not always observable. This article considers two estimation methods and shows that under the assumption of selection on the observables the resulting estimators are asymptotically normal. As an application of these results this article proposes a new estimator for the average treatment effect parameter. A simulation study illustrates the finite sample properties of the proposed estimators.     

Survival Estimation with Missing Censoring Times for the Generalized Koziol–Green Model

ABSTRACT

When analyzing time-to-event data, there are various situations in which right censoring times for unfailed units are missing. In that context, by taking a supplementary sample of a convenient percentage of unfailed units, we propose a semi-parametric method for estimating a survival function under the natural extension of the Koziol–Green model to double random censoring. Some large sample properties of this estimator are derived. We prove uniform strong consistency and asymptotic weak convergence to a Gaussian process. A simulation study is also presented in order to analyze the behavior of the proposed estimator.     

Convergence in the Innovative Performance of the European Union Countries

The aim of this work is to study whether a process of convergence in innovation in the European countries has occurred or not, by analysing the relative changes in the innovative position of the European countries during the period 2002–2006. Special attention is paid to the relative changes that have occurred in the recently acceded countries and to the poorest countries of the EU-15. The data used in this research come from the fourth and fifth wave of the Community Innovation Survey elaborated by EUROSTAT and collected in different Member States of the European Union. The statistical technique used is the multiple factorial analysis. The study has been carried out on two different sets of firms. On the one hand, it has considered all manufacturing firms (innovative and non-innovative firms) and, on the other, only the innovative manufacturing firms. The results show a moderate convergence process in innovation in the manufacturing as a whole, but not in the innovative firms.