Weighted averaging,Jeffrey conditioning and invariance

Jeffrey conditioning tells an agent how to update her priors so as to grant a given probability to a particular event. Weighted averaging tells an agent how to update her priors on the basis of testimonial evidence, by changing to a weighted arithmetic mean of her priors and another agent’s priors. We show that, in their respective settings, these two seemingly so different updating rules are axiomatized by essentially the same invariance condition. As a by-product, this sheds new light on the question how weighted averaging should be extended to deal with cases when the other agent reveals only parts of her probability distribution. The combination of weighted averaging (for the events whose probability the other agent reveals) and Jeffrey conditioning (for the events whose probability the other agent does not reveal) is a comprehensive updating rule to deal with such cases, which is again axiomatized by invariance under embedding. We conclude that, even though one may dislike Jeffrey conditioning or weighted averaging, the two make a natural pair when a policy for partial testimonial evidence is needed.     

Mobile Air Monitoring: Measuring Change in Air Quality in the City of Hamilton, 2005–2010

This paper examines the change in air pollutant concentrations between 2005 and 2010 occurring in the City of Hamilton, Ontario, Canada. After analysis of stationary air pollutant concentration data, we analyze mobile air pollutant concentration data. Air pollutants included in the analysis are CO, PM_2.5, SO₂, NO, NO₂, and NO_X. Stationary monitoring indicates a continuous reduction in air pollutant concentrations. Stationary monitors only cover a small spatial extent of Hamilton. Mobile monitoring of air pollutant concentrations, averaged over census tract boundaries, indicates both improvement and decline in air quality. These improvements and declines in air quality are spatially clustered throughout Hamilton. Mobile data indicated significant decline in median pollutant concentration for CO, SO₂, PM_2.5, and NO₂; but significant increase for NO and NO_X. Air quality change in Hamilton is spatially heterogeneous, and is not captured based on the current stationary monitoring network. Coupling of mobile and stationary air pollutant concentration monitoring provides a more accurate spatial assessment of local air quality.     

Prevention of musculoskeletal disorders (MSDs) in office work: a case study

Twelve recently built office work stations, where jobs imply continued use of information and communication technologies, were analyzed for ergonomic risk factors. Based on a literature review of ergonomic recommendations for computer and general office work, a checklist was devised for assistance in identifying inadequate ergonomic situations, a process that was informed by pain complaints information. RULA (Rapid Upper Limb Assessment) was selected to estimate the risk of MSDs, considering the criteria of applicability and appropriateness to the case studied. This method was applied by an occupational health and safety technician to the most critical job observed in the workplace. Criticality was estimated through observations aided by the systematic use of a checklist tailored to the specific office scenario. Recommendations for change were provided for implementation in all workplaces in the office, in order to improve work conditions, and guide the setup of a MSD prevention training program.     

Modeling initiation into drug injection among street youth

This study aimed at examining the predictors of initiation into drug injection among street youth using social cognitive theory framework. A prospective cohort study based on semi-annual interviews was carried out. Psychosocial determinants referred to avoidance of initiation. Other potential predictors were: sociodemographic characteristics, relationships with injectors, parent's substance misuse, drug use patterns, homelessness, survival sex, sexual abuse. Independent predictors were identified using Cox proportional hazards regression models. Among the 352 participants, high control beliefs about avoidance of initiation was protective while younger age, daily alcohol consumption, heroin use, cocaine use, and survival sex all increased risk of initiation. Preventive strategies targeting street youth should both enhance youth's control beliefs and actual control over their substance use and improve their life conditions.     

Rule-Governed Behavior: Teaching a Preliminary Repertoire of Rule-Following to Children With Autism

Rule-governed behavior is generally considered an integral component of complex verbal repertoires but has rarely been the subject of empirical research. In particular, little or no previous research has attempted to establish rule-governed behavior in individuals who do not already display the repertoire. This study consists of two experiments that evaluated multiple exemplar training procedures for teaching a simple component skill, which may be necessary for developing a repertoire of rule-governed behavior. In both experiments, children with autism were taught to respond to simple rules that specified antecedents and the behaviors that should occur in their presence. In the first study, participants were taught to respond to rules containing "if/then" statements, where the antecedent was specified before the behavior. The second experiment was a replication and extension of the first. It involved a variation on the manner in which rules were presented. Both experiments eventually demonstrated generalization to novel rules for all participants; however variations to the standard procedure were required for several participants. Results suggest that rule-following can be analyzed and taught as generalized operant behavior and implications for future research are discussed.     

Prisoner Citizen: Carl Upchurch,Labeling Theory,and Symbolic Interactionism

The life of Carl Upchurch offers a personal example of labeling theory and symbolic interactionism in action. According to labeling theory, behaviors are explained by the reactions received from audiences. Three of the audiences that respond to the behavior of an individual are society at large, agents of social control, and significant others. Upchurch demonstrated how deviant behavior became normal and how being labeled deviant made normal behavior difficult. Symbolic interactionism stresses the importance of learning and social interaction and sees people as being proactive rather than reactive, active and not passive. Through his love of books, Upchurch took charge of his life and moved from being a prisoner citizen to an educator.     

Why Do Some Democratic Countries Join More Intergovernmental Organizations Than Others?*

Objective. This study investigates whether variations in democratic institutions influence foreign policy outcomes. Specifically, it examines whether democracies differ systematically in their inclination to join international organizations. Methods. The study performs negative binomial estimation analysis of the relationship between IGO membership and variations in democratic structure. Results. It finds that a more competitive party system and multiple legislative chambers, especially for wealthy and stable Western democracies, contribute to more IGO memberships. Conclusions. From our findings we infer that consensus democracies adopt a kinder, gentler foreign policy that includes more willingness to participate in multilateral, cooperative international institutions, relying on negotiation and compromise to reach mutually acceptable arrangements for dealing with common problems. This assertion fits with a fundamental Kantian thesis: that the more representative and accountable a society's political institutions are, the more peaceful that society is likely to be.     

A New Spatial Skew-Normal Random Field Model

Skewness is often present in a wide range of geostatistical problems, and modeling it in the spatial context remains a challenging problem. In this article, we propose and study a new class of spatial skew-normal random fields, defined in terms of the closed multivariate skew-normal distribution. Such fields can be written as the sum of two independent fields: one Gaussian and the other truncated Gaussian. We derive theoretical expressions for the first- and second-order moments, and use them within a method of moments based procedure to estimate the parameters of the model. Data simulated from the model are used to illustrate the methodology developed.     

Environmental pressures and marketing in the 1970s

Leadership in both private and public institutions is devoting considerable attention to the effects of rapidly increasing rates of environmental change on its areas of responsibility. To fulfill the requirements of their obligations to customers and the firm, marketing executives, particularly, must be aware of and responsive to events external to the business.The study upon which this article is based, sought to uncover the perceptions of senior marketing executives in leading U.S. industrial corporations concerning the importance of several environmental issues to their marketing strategies, tactics and operating performance expectations for the 1970s. Awareness and response tendencies of executives to the following items were investigated: (1) the role of marketing in the firm; (2) consumerism; (3) air and water pollution; (4) urban substandard housing; (5) deterioration of downtown areas; (6) consumer market changes; (7) distribution system changes; (8) civil rights movement; (9) nature and intensity of competition. The competition was completed just prior to the emergence of the energy crisis and the removal of price controls in the U.S.