Aggregation of isotropic autoregressive fields

This note constitutes a corrigendum to the article of Azomahou [2009, Memory properties and aggregation of spatial autoregressive models. J. Statist. Plann. Inference, 139, 2581-2597]. The aggregation of isotropic four nearest neighbors autoregressive models on the lattice Z², with random coefficient, is investigated. The spectral density of the resulting random field is studied in details for a large class of law of the AR coefficient. Depending on this law, the aggregated field may exhibit short memory or isotropic long memory.     

On the Validity of the Bootstrap in Non‐Parametric Functional Regression

Abstract. We consider the functional non‐parametric regression model Y= r( χ )+?, where the response Y is univariate, χ is a functional covariate (i.e. valued in some infinite‐dimensional space), and the error ? satisfies E(? | χ ) = 0. For this model, the pointwise asymptotic normality of a kernel estimator of r (·) has been proved in the literature. To use this result for building pointwise confidence intervals for r (·), the asymptotic variance and bias of need to be estimated. However, the functional covariate setting makes this task very hard. To circumvent the estimation of these quantities, we propose to use a bootstrap procedure to approximate the distribution of . Both a naive and a wild bootstrap procedure are studied, and their asymptotic validity is proved. The obtained consistency results are discussed from a practical point of view via a simulation study. Finally, the wild bootstrap procedure is applied to a food industry quality problem to compute pointwise confidence intervals.     

Experiments with truth. A sociological variation on William James's Varieties of Religious Experience

William James's Varieties of Religious Experience is a classic psycho‐philosophical study of the experience of the sacred and of its practical effects on the ordinary life of extraordinary persons. In a pragmatic variation of Kant's proof of god's existence, James uses personal accounts of converts to empirically demonstrate that there's “something” that has causal effects on the well‐being of the person. While the article is largely sympathetic to James explorations of the mystical, it offers a sociological variation on the Varieties that foregrounds the social, cultural and political aspects of religion.     

Inequality decomposition values: the trade-off between marginality and efficiency

This paper presents a general procedure for decomposing income inequality measures by income sources. The methods of decomposition proposed are based on the Shapley value and extensions of the Shapley value of transferable utility cooperative games. In particular, we find that Owen’s value can find an interesting application in this context.We show that the axiomatization by the potential of Hart and Mas-Colell remains valid in the presence of the domain restriction of inequality indices. We also examine the properties of these decomposition rules and perform a comparison with Shorrocks’ decomposition rule properties.     

Comment vendre un produit incertain ? Activités de détachement et d’attachement d’une firme d’agrofourniture

This article examines the sales practices of a French agricultural supplies company whose products have uncertain qualities and contested effects. We show that this characteristic leads the sales technicians responsible for selling these products to develop arguments that make extensive use of a rhetoric aiming to detach the clients from their competitors. Given how difficult it is to establish an objective assessment of products’ intrinsic qualities, we also show how attachments are built around a broad-ranging solution that in particular includes providing consulting services for farmers. More generally, in the analysis of sales work, the commerce of these uncertain products invites one to think of processes of attachment and detachment in symmetrical terms.     

How do actors shape social networks during the process of new product development?

Recent studies on new-idea generation and development have highlighted the role played by network structure in the genesis of new combinations or the process of selecting ideas. However, less attention has been paid to the factors that entice actors to shape social networks during the process of the development of new ideas.This research was conducted in an R&D facility of a semi-conductor company. We analysed the generation of five creative projects and their development over a four-year period. We used a longitudinal approach and collected data through interviews and observations to identify the creative contributions and the actors who were involved at different time periods for each project. We mapped the relationships between actors who contributed to the development of each idea through creative thinking and/or helped it to become accepted both internally and externally over three-year windows. This method generated data on network evolution.We also carried out a qualitative analysis and identified four main factors explaining why actors turn to others during the idea-development process: (1) to gain access to information; (2) to enhance credibility; (3) to exercise one’s influence; and (4) to gain access to knowledge through people or objects. We demonstrate that different types of ties or network structures are relied upon to reap different kinds of benefits. This may partially explain network evolution as an idea progresses through different development stages.     

WOMEN PREFER LARGER GOVERNMENTS: GROWTH,STRUCTURAL TRANSFORMATION,AND GOVERNMENT SIZE

The increase in income per capita is accompanied, in virtually all countries, by two changes in economic structure: the increase in the share of government spending in gross domestic product (GDP), and the increase in female labor force participation. We argue that these two changes are causally related. We develop a growth model based on Galor and Weil (1996) where female participation in market activities, fertility, and government size, in addition to consumption and saving, is endogenously determined. Rising incomes lead to a rise in female labor force participation as the opportunity cost of staying at home and caring for the children increases. In our model, higher government spending decreases the cost of performing household chores, including, but not limited to, child rearing and child care, as in Rosen (1996) . We also use a wide cross‐section of data for developed and developing countries and show that higher market participation by women is positively and robustly associated with government size. We then investigate the causal link between participation and government size using a novel unique data set that allows the use of the relative price of productive home appliances as an instrumental variable. We find strong evidence of a causal link between female market participation and government size. This effect is robust to the country sample, time period, and a set of controls in the spirit of Rodrik (1998) . (JEL O4, E62, H11)     

Interspecies Extrapolation of Physiological Pharmacokinetic Parameter Distributions

Three methods (multiplicative, additive, and allometric) were developed to extrapolate physiological model parameter distributions across species, specifically from rats to humans. In the multiplicative approach, the rat model parameters are multiplied by the ratio of the mean values between humans and rats. Additive scaling of the distributions is denned by adding the difference between the average human value and the average rat value to each rat value. Finally, allometric scaling relies on established extrapolation relationships using power functions of body weight. A physiologically-based pharmacokinetic model was fitted independently to rat and human benzene disposition data. Human model parameters obtained by extrapolation and by fitting were used to predict the total bone marrow exposure to benzene and the quantity of metabolites produced in bone marrow. We found that extrapolations poorly predict the human data relative to the human model. In addition, the prediction performance depends largely on the quantity of interest. The extrapolated models underpredict bone marrow exposure to benzene relative to the human model. Yet, predictions of the quantity of metabolite produced in bone marrow are closer to the human model predictions. These results indicate that the multiplicative and allometric techniques were able to extrapolate the model parameter distributions, but also that rats do not provide a good kinetic model of benzene disposition in humans.     

Modeling Benzene Pharmacokinetics Across Three Sets of Animal Data: Parametric Sensitivity and Risk Implications

Typically, the uncertainty affecting the parameters of physiologically based pharmacokinetic (PBPK) models is ignored because it is not currently practical to adjust their values using classical parameter estimation techniques. This issue of parametric variability in a physiological model of benzene pharmacokinetics is addressed in this paper. Monte Carlo simulations were used to study the effects on the model output arising from variability in its parameters. The output was classified into two categories, depending on whether the output of the model on a particular run was judged to be generally consistent with published experimental data. Statistical techniques were used to examine sensitivity and interaction in the parameter space. The model was evaluated against the data from three different experiments in order to test for the structural adequacy of the model and the consistency of the experimental results. The regions of the parameter space associated with various inhalation and gavage experiments are distinct, and the model as presently structured cannot adequately represent the outcomes of all experiments. Our results suggest that further effort is required to discern between the structural adequacy of the model and the consistency of the experimental results. The impact of our results on the risk assessment process for benzene is also examined.