Quantitative Risk Assessment of FMD Virus Transmission via Water

Foot-and-mouth disease (FMD) is a viral disease of domesticated and wild cloven-hoofed animals. FMD virus is known to spread by direct contact between infected and susceptible animals, by animal products such as meat and milk, by the airborne route, and mechanical transfer on people, wild animals, birds, and by vehicles. During the outbreak of 2001 in the Netherlands, milk from dairy cattle was illegally discharged into the sewerage as a consequence of transport prohibition. This may lead to contaminated discharges of biologically treated and raw sewage in surface water that is given to cattle to drink. The objective of the present study was to assess the probability of infecting dairy cows that were drinking FMD virus contaminated surface water due to illegal discharges of contaminated milk. So, the following data were collected from literature: FMD virus inactivation in aqueous environments, FMD virus concentrations in milk, dilution in sewage water, virus removal by sewage treatment, dilution in surface water, water consumption of cows, size of a herd in a meadow, and dose-response data for ingested FMD virus by cattle. In the case of 1.6 x 10(2) FMD virus per milliliter in milk and discharge of treated sewage in surface water, the probability of infecting a herd of cows was estimated to be 3.3 x 10(-7) to 8.5 x 10(-5), dependent on dilution in the receiving surface water. In the case of discharge of raw sewage, all probabilities of infection were 100 times higher. In the case of little dilution in small rivers, the high level of 8.5 x 10(-3) is reached. For 10(4) times higher FMD virus concentrations in milk, the probabilities of infecting a herd of cows are high in the case of discharge of treated sewage (3.3 x 10(-3) to 5.7 x 10(-1)) and very high in the case of discharge of raw sewage (0.28-1.0). It can be concluded that illegal and uncontrolled discharges of contaminated milk into the sewerage system may lead to high risks to other cattle farms at 6-50 km distance of the location of discharge within one day. This clearly underlines current measures that prohibit such discharges, and also asks for strict control. This risk assessment clearly demonstrated the potential significance of FMD virus transmission via water, and the results will be useful on an international scale, and could also serve as a basis for other FMD risk-assessment models.     

A robust prediction error criterion for pareto modelling of upper tails

Estimation of the Pareto tail index from extreme order statistics is an important problem in many settings. The upper tail of the distribution, where data are sparse, is typically fitted with a model, such as the Pareto model, from which quantities such as probabilities associated with extreme events are deduced. The success of this procedure relies heavily not only on the choice of the estimator for the Pareto tail index but also on the procedure used to determine the number k of extreme order statistics that are used for the estimation. The authors develop a robust prediction error criterion for choosing k and estimating the Pareto index. A Monte Carlo study shows the good performance of the new estimator and the analysis of real data sets illustrates that a robust procedure for selection, and not just for estimation, is needed.     

Fertility and economic activity of women in Guatemala city, 1964

Data from a five percent census sample reveal that in Guatemala City in 1964 economically active women, especially domestic servants, had lower cumulative fertility than inactive women, partly because larger proportions of them had never married and were childless. However, even among ever married mothers there was a substantial differential, which was not due to differences in age at first birth. With respect to all women, cross tabulation and regression analysis show that age, marital status and educational attainment were more strongly associated with fertility than was activity status, but the latter also had a significant net association. Selection for sterility was not likely. Being contrary to expectations expressed in the literature, the very low fertility of the domestics received further attention. Live-in domestics had considerably lower fertility than those who lived out, which was also the case in the United States in 1960. These data and other evidence strongly suggest that this differential is due to a widespread employer preference for single or childless women. The concept of role incompatibility is therefore inapplicable to domestic servants. These findings add to the considerable evidence showing lower fertility among economically active women in large urban places in Latin America.     

Housing tenure,structure, and crowding among Latino households

This article examines the effect of federal housing and public assistance programs on the housing quality of different Latino households. The research tests models of crowding and housing tenure and structure for Latino households. The data for this research are from the 1990 Latino National Political Survey-Panel Study of Income Dynamics (LNPS-PSID). Findings reveal that housing and public assistance programs do help alleviate crowding among the Latino population, but they do not help Latino households achieve ownership of a single-family home. All the demographic variables in the model contribute to the explanation of crowding, and a majority also significantly explain housing tenure and structure. Significant differences are found among Latino subgroups in the explanatory variables for crowding, tenure, and structure. She is also the director of the Center for the Study of Aging at Illinois State. Her research interests include housing of minority households and congregate housing for the elderly. She received her Ph.D. from Iowa State University. Her research interests include housing needs of Latino households, resource management of female-headed Puerto Rican households, fertility decisions of Puerto Rican women, and student labor force participation. She received her Ph.D. from the University of Illinois.     

Effort Observability,Incentive Systems,and Organizational Forms

This paper analyses the choice between a centralized and a decentralized organizational structure focusing on the relationship existing between the allocation of decision rights, the degree of observability of effort and the use of different compensation systems. Profitable production is realized thanks to good information being available during the project selection stage and hard work being performed in the implementation stage. Selection of projects may be made by the principal (hierarchy) or by the agent (delegation). Under the hierarchical system, the principal's participation in the design of projects allows her to gather useful information for the design of a more accurate compensation system. Therefore, we analyse the trade‐off between optimal use of available information and accuracy of incentive systems, which emerges in the choice of organizational form.     

English perceptions of elder abuse

The purpose of this exploratory study was to investigate an English sample's perceptions on elder abuse, inflicted by adult children against their aging parents. Fifty participants (14 males, 46 females) provided examples of extreme, moderate, and mild elder abuse. As examples of extreme abuse, most participants mentioned neglect and physical aggression. Various forms of neglect and psychological abuse were their most common examples of moderate and mild abuse. References to physical aggression appeared most often as examples of extreme abuse rather than of moderate or mild abuse. Within these main categories, the specific subtypes most frequently mentioned by the sample included physical neglect, psychological neglect, verbal abuse, and deprivation. More females than males provided examples of financial abuse and physical neglect. Females were also more likely than males to list psychological neglect as an extreme form of abuse and disrespect as a form of mild abuse. At the moderate level, males referred to abuse relating to power more often than females. A positive relationship was found between age and the number of examples of physical neglect given at the moderate level and the number of examples of emotional abuse given at the mild level.     

Measuring Kurtosis by Right and Left Inequality Orders

The question of how to measure kurtosis in both symmetric and asymmetric distributions is addressed using the kurtosis diagram of Zenga (2006 Zenga , M. ( 2006 ). Kurtosis . In : Kotz , S. , Read , C. B. , Balakrishnan , N. , Vidakovic , B. , eds. Encyclopedia of Statistical Sciences. 2nd ed . New York : John Wiley and Sons . [Google Scholar]). Kurtosis is related to inequality at either side of the median, and we establish a hierarchy of kurtosis orderings in which the kurtosis diagram stands at the weakest level. A sufficient condition for constructing kurtosis measures compatible with such ordering is provided. The merits of the proposed approach in both clarifying and formalizing the idea of kurtosis are evaluated and examples are discussed throughout.