Palm Distributions for Log Gaussian Cox Processes

This paper establishes a remarkable result regarding Palm distributions for a log Gaussian Cox process: the reduced Palm distribution for a log Gaussian Cox process is itself a log Gaussian Cox process that only differs from the original log Gaussian Cox process in the intensity function. This new result is used to study functional summaries for log Gaussian Cox processes.     

Preference intensity representation: strategic overstating in large elections

If voters vote strategically, is it useful to offer them the possibility of expressing nuanced opinions, or would they always overstate the intensity of their preferences? For additive voting rules, say that a ballot is extremal if it is neither abstention-like nor can be expressed as a mixture of the available ballots. We give a sufficient condition for strategic equivalence: if two rules share the same set of extremal ballots (up to an homothetic transformation), they are strategically equivalent in large elections. This condition is also necessary for the strategic equivalence of positional rules. These results do not hold for small electorates.     

Invisible computer for collaborative design: evaluation of a multimodal sketch-based environment

In the areas of design, especially in architectural design, collaboration has become an important challenge. The specialization of skills increase, work teams are more and more extensive and the geographic distance between them increases too. The economic and ecological stakes related to remote collaboration are an evidence. This context involves the need to support most efficiently possible remote working meetings. We present the Distributed Collaborative Digital Studio (DSDC), a tool designed to recreate, in distant situations, the context of copresence meetings. This shared environment is created in the "invisible computer" approach [11]. The idea is that the tool should disappear from user's consciousness. Indeed, creative design activities require some fluidity in their process. Therefore, any involuntary interruption created by the system can potentially brake creativity. In this perspective, we investigate specifically the "invisibility" of our environment. To do this, we propose a framework for the operationalization of the concept and a methodology to test the system invisibility. This methodology was applied through a case study consisting of a corpus of 12 hours of remote collaborative design sessions with the DSDC. We highlight the learning effects while using our system, conclude on its effectiveness and discuss our methodology.     

From needs to requirements for computer systems: the added value of ergonomics in needs analysis

It is widely recognised that ergonomists must contribute during needs analysis. However, few studies have investigated the specific contributions of ergonomists at this stage of the design process. In this study, this contribution is studied through the requirement document produced by the design team. For each requirement, the source (i.e. who formulated the requirement), justification (why the requirement is needed), type (functional, interaction, operational, physical, organizational), and scope (entire system or part thereof) were analysed. Results indicate that the various actors are complementary and work collectively to define the various dimensions of the system. With end-users, the ergonomist worked on the global aspects of the system: function, conditions of use and organizational dimension. Alone, he defined the global interaction of the system. The various functions derived from the global function were defined in collaboration with engineers. However, while engineers contributed to defining how these functions would work, as well as their technical conditions of use, the ergonomist focused on their purpose, and, with end-users, on their organizational aspects. Finally, results suggest that neither the ergonomist's specific knowledge in ergonomics, nor work analysis were sufficient to derive his requirements; both are mandatory.     

Raccoon use of the urban matrix in the Baltimore Metropolitan Area, Maryland

The raccoon is often considered a synanthropic species; however, most urban research on this species has been restricted to urban parks or green spaces. Little is known about the persistence of synanthropic characteristics in the raccoon within the urban matrix. We examined density, den selection, home range size, habitat selection, and survival for adult raccoons (Procyon lotor) during summer (June?CAugust) and autumn (September?CNovember) in two residential neighborhoods, Linthicum located inland, and Riviera Beach on a peninsula in the Potomac river, in Southern Maryland. Den site selection varied by gender (P?=?0.0002) and study site (P?=?0.052), and study site interacted with gender (P?=?0.0063), with female raccoons denning preferentially on the ground and male raccoons in human structures in Riviera Beach while in Linthicum females denned preferentially in trees and males avoided human structures. Seasonal home range size was larger for males (P?<?0.0001) than females at both sites. Habitat selection varied at different hierarchical levels, and between gender, season and site. Intersite differences in habitat selection were apparent at the second order and third order scale. Aquatic and urban habitat was ranked high and woodland consistently lowest in second order scale at Riviera Beach while urban habitat was consistently ranked lowest at Linthicum where woodland ranked highest. Between the hierarchal scales (2nd and 3rd order) a difference in habitat selection occurred at Linthicum only where urban habitats ranked lowest at 3rd order. The differences in patterns of habitat selection we observed between two urban sites at different hierarchical scales suggest that resource selection is dependent upon the specific characteristics of the site and that raccoons exhibit variable responses to changes in landscape features. Finally, male survival tended to be lower (P?=?0.079) than female survival in both study sites. Our results reveal that raccoons can continue to exhibit synanthropic characteristics within the urban matrix even in areas with little natural habitat. This ability to adjust to different levels of development allows the raccoon to occur throughout most parts of the urban landscape, which has important management implications for human-raccoon conflicts and disease management.     

Two Case Studies on Family Work with Eating Disorders and Body Image Issues

This article highlights the need for clinicians who work with eating disorders and body image problems to address the deeper family issues underlying these symptoms. The authors propose an eclectic approach including family systems, structural and experiential family therapy theory as a guide. The paper begins with an overview of family therapy theories currently used in the treatment of eating disorders, and goes into greater detail about the three theories highlighted in the eclectic model proposed. The authors present two cases with actual case dialogue, demonstrating how they used this composite model. This article has both theoretical and practical implications for clinicians working in the field.     

Non-linear regression models for Approximate Bayesian Computation

Approximate Bayesian inference on the basis of summary statistics is well-suited to complex problems for which the likelihood is either mathematically or computationally intractable. However the methods that use rejection suffer from the curse of dimensionality when the number of summary statistics is increased. Here we propose a machine-learning approach to the estimation of the posterior density by introducing two innovations. The new method fits a nonlinear conditional heteroscedastic regression of the parameter on the summary statistics, and then adaptively improves estimation using importance sampling. The new algorithm is compared to the state-of-the-art approximate Bayesian methods, and achieves considerable reduction of the computational burden in two examples of inference in statistical genetics and in a queueing model.     

Managing Corporate Knowledge Experiences with SODA and V·I·S·A

It is often said that success in today's competitive environment depends on the acquisition and application of sound, relevant knowledge. This paper introduces two management science approaches that have been used for the effective management of knowledge, towards the development of strategy, planning and decision making, in a wide range of organizational settings. Both approaches make use of computer technology to provide a flexible and interactive environment incorporating a visual representation of the problem. The paper briefly describes each approach, together with a case study illustrating its use in practice. A number of common themes relevant to the management of knowledge are identified and discussed. The themes highlight the benefits which arise through the use of computer technology alongside a number of issues relevant to the management of the group process.     

When Passion Leads to Problematic Outcomes: A Look at Gambling

Vallerand et al. (2003) have proposed that individuals can have two distinct types of passion toward an activity. Harmonious passion, an internal force leading one to choose to engage in the activity, is proposed to be associated with positive consequences. Obsessive passion, an internal pressure forcing one to engage in an activity, is posited to be associated with negative consequences. The present study sought to determine the role of the two types of passion in various cognitive and affective states associated with dependence and problems with gambling. Participants (n = 412) were recruited at the Montréal Casino and given a questionnaire measuring passion toward gambling, as well as consequences associated with dependence and problem gambling. Results showed that obsessive passion for gambling predicted poorer vitality and concentration in daily tasks, as well as increased rumination, anxiety, negative mood, guilt, and problem gambling. These relations were not found for harmonious passion for gambling. Results are discussed in light of the motivational approach to passion (Vallerand et al., 2003).