Simulated classical tests in multinomial probit models

This paper compares the application of different versions of the simulated counterparts of the Wald test, the score test, and the likelihood ratio test in one- and multiperiod multinomial probit models. Monte Carlo experiments show that the use of the simple form of the simulated likelihood ratio test delivers relatively robust results regarding the testing of several multinomial probit model specifications. In contrast, the inclusion of the Hessian matrix of the simulated loglikelihood function into the simulated score test and (in the multiperiod multinomial probit model) particularly the inclusion of the quasi-maximum likelihood theory into the simulated likelihood ratio test leads to substantial computational problems. The combined application of the quasi-maximum likelihood theory with the simulated Wald test or the simulated score test is not systematically superior to the application of the other versions of these two simulated classical tests either. Neither an increase in the number of observations nor in the number of random draws in the incorporated Geweke-Hajivassiliou-Keane simulator systematically lead to more precise conformities between the frequencies of type I errors and the basic significance levels. An increase in the number of observations only decreases the frequencies of type II errors, particularly regarding the simulated classical testing of multiperiod multinomial probit model specifications.     

Time with Children: Do Fathers and Mothers Replace Each Other When One Parent is Unemployed?

This article aims to study the substitution of parental time between the mother and the father. Taking the “experience” of unemployment as a release from the time constraint, we analyse time transfers between partners in such a situation. A bivariate Tobit model is applied on the French time-use data. It shows that parents quite rarely substitute the time devoted to children between each other, except for child transportation and childcare. Parents do not want to relinquish their parental activities, a fact which reflects their desire to contribute to the children’s education, and the contribution of parental time to the balance of power between spouses. Exchanges remain asymmetric: non-employed fathers release less their partner from parental tasks than unemployed mothers do, which reflects the weight of gender social norms.     

A Parallel between Regret Theory and Outranking Methods for Multicriteria Decision Making Under Imprecise Information

Incorporation of the behavioral issues of the decision maker (DM) is among the aspects that each Multicriteria Decision Making (MCDM) method implicitly or explicitly takes into account. As postulated by regret theory, the feelings of regret and rejoice are among the behavioral issues associated with the entire decision making process. Within the context of MCDM, the DM may feel regret, when the chosen alternative is compared with another one having at least one better criterion value. PROMETHEE II is a widely known MCDM method that makes no explicit incorporation of regret attitude of the DM. In this paper, we elaborate on the applicability of regret theory to MCDM context. In particular, we investigate the findings of regret theory and explore the parallel between regret theory and PROMETHEE II method. Relying on the concepts of regret theory, we demonstrate how a decision that is made using a PROMETHEE II based outranking method conforms to the regret attitude of the DM.     

Limited Access: Disparities in Flexible Work Schedules and Work-at-home

This research tests predictions regarding potential disparities among the employed by personal characteristics in the ability to vary the starting and ending times of their workday and engage in work from home. Women and African-Americans possess less access to flexible work schedules, even when controlling for most job characteristics. Married men have more access, but only if they are parents, and mothers only if they have pre-school-age children. Workers with part-time or long hours gain far greater access. Work-at-home is more common among women, the married and parents-thus, relatively more reflective of family demands. The results suggest where public and organizational policies could be focused to spread flexible work arrangements more toward those who both most value it and lack it.     

Nonconglomerative coherent conditional probabilities in statistical inference

Noteworthy connections among conglomerability, countable additivity and coherence are discussed in detail, reaching the conclusion that nonconglomerable conditional probabilities must not be doomed and play a significant role in statistical inference. Extended and updated version of a contributed paper presented at the International Conference on “Information Processing and Management of Uncertainty in knowledge-based systems”, IPMU 2004, Perugia, Italy.     

Inference in hybrid Bayesian networks using dynamic discretization

We consider approximate inference in hybrid Bayesian Networks (BNs) and present a new iterative algorithm that efficiently combines dynamic discretization with robust propagation algorithms on junction trees. Our approach offers a significant extension to Bayesian Network theory and practice by offering a flexible way of modeling continuous nodes in BNs conditioned on complex configurations of evidence and intermixed with discrete nodes as both parents and children of continuous nodes. Our algorithm is implemented in a commercial Bayesian Network software package, AgenaRisk, which allows model construction and testing to be carried out easily. The results from the empirical trials clearly show how our software can deal effectively with different type of hybrid models containing elements of expert judgment as well as statistical inference. In particular, we show how the rapid convergence of the algorithm towards zones of high probability density, make robust inference analysis possible even in situations where, due to the lack of information in both prior and data, robust sampling becomes unfeasible.     

Statistical consulting at German universities: Results of a survey

The article presents the results of a survey on statistical consulting at German universities, where the survey focused on obtaining information on when, where and to whom statistical consulting is provided. We investigate the financial frame of the activity and question the advantages and disadvantages from a consultant’s point of view.     

Some preservation results of NBUC aging property with applications

This paper develops a new characterization of NBUC aging property, and investigates its preservation properties both under monotonic anti-star-shaped transformations and under the non-homogeneous Poisson shock models.     

Cognitive Risk Factors to the Development of Anxiety and Depressive Disorders in Adolescents

This exploratory study examines cognitive risk factors, anxiety sensitivity, and positive and negative affect, as related to the development of anxiety and depression. In a mailed survey, adolescents completed the Child Anxiety Sensitivity Index and the Positive and Negative Affectivity Scale. Previous research utilized the broad and unified variable of anxiety sensitivity as a predictor of anxiety. In this study, we separate and examine the four specific factors of anxiety sensitivity: mental incapacitation concerns, social concerns, disease concerns, and unsteady concerns, and relate it to specific anxiety disorders and depression. Results indicate good convergent validity and improved divergent validity when utilizing the four factors of anxiety sensitivity as compared to using it as one construct. Results also suggest: (1) OCD and GAD share numerous similarities and (2) the importance of the role of negative affectivity in anxiety and depression. Being aware of the components of anxiety sensitivity and how they relate to specific anxiety disorders can help a social worker when rendering a diagnosis. Part of the data presented in this article was from David A. Dia’s doctoral dissertation.     

Fengshui theory in urban landscape planning

The spatial configuration of urban landscapes results from cumulative interactions between human activities and the physical environment. Traditional philosophies and cultural legacies have had important influences on urban development and planning in East Asia. In Seoul, traditional land use practices based on ‘Fengshui’ have significantly contributed to human-mediated patterns of landscape changes, in addition to the role of the socio-economic background (development) and other human activities. The concept of Fengshui was originally founded upon people’s empirical cognition of natural landscape patterns. Recently, however, advanced economic development, westernization and urbanization have been rapidly altering the old traditions of the holistic landscape systems through changing urban planning practices. Since the type, scale, frequency, distribution and spreading pattern of environmental and human disturbances have been changed, a new paradigm for urban landscape planning is necessary to maintain the ecological and cultural integrity of landscapes in Korea. In this paper, we discuss recent concepts and methods of landscape ecology and urban planning from the viewpoint of Fengshui, the traditional land use patterns in Seoul, whose application has so far been restricted only to traditional land evaluation. We conclude that, to maintain the sustainability of the urban landscape, it is necessary to develop a new urban planning framework for the region that is based on the integration between landscape ecology principles with the traditional concepts of Fengshui.