Strategic, sincere, and heuristic voting under four election rules: an experimental study

We report on laboratory experiments on voting. In a setting where subjects have single-peaked preferences, we find that the rational choice theory provides very good predictions of actual individual behavior in one-round and approval voting elections but fares poorly in explaining vote choice under two-round elections. We conclude that voters behave strategically as far as strategic computations are not too demanding, in which case they rely on simple heuristics (under two-round voting) or they just vote sincerely (under single transferable vote).     

Does any mother’s body odor stimulate interest in mother’s face in 4‐month‐old infants?

Little is known about the effects of olfaction on visual processing during infancy. We investigated whether and how an infant's own mother's body odor or another mother's body odor affects 4‐month‐old infants’ looking at their mother's face when it is paired with a stranger's face. In Experiment 1, infants were exposed to their mother's body odor or to a control odor, while in Experiment 2, infants were exposed to a stranger mother's body odor while their visual preferences were recorded. Results revealed that infants looked more at the stranger's female face in presence of the control odor but that they looked more at their mother's face in the context of any mother's body odors. This effect was due to a reduction of looking at the stranger's face. These findings suggest that infants react similarly to the body odor of any mother and add to the growing body of evidence indicating that olfactory stimulation represents a pervasive aspect of infant multisensory perception.     

Immigration and Natives’ Attitudes towards the Welfare State: Evidence from the European Social Survey

Does immigration reduce natives’ support for the welfare state? Evidence from the European Social Survey (2002/2003) suggests a more qualified relation. For Europe as a whole, there is only weak evidence of a negative association between the perceived presence of immigrants and natives’ support for the welfare state. However, this weak average relationship masks considerable heterogeneity across countries. We distinguish two channels through which immigration could affect natives’ support for the welfare state: a pure dislike of immigrants and concerns about the economic consequences of immigration. We find that natives who hold both negative views react much more negatively to a given perceived share of immigrants than natives who hold neither view. However, there is no clear pattern concerning the relative importance of the two channels. Finally, we find that natives who hold either of these negative views of immigrants tend to be less supportive of the welfare state independently of the perceived presence of immigrants.     

High-dimensional VAR with low-rank transition

Statistics and Computing - We propose a vector auto-regressive model with a low-rank constraint on the transition matrix. This model is well suited to predict high-dimensional series that are...     

LASSO-type estimators for semiparametric nonlinear mixed-effects models estimation

Parametric nonlinear mixed effects models (NLMEs) are now widely used in biometrical studies, especially in pharmacokinetics research and HIV dynamics models, due to, among other aspects, the computational advances achieved during the last years. However, this kind of models may not be flexible enough for complex longitudinal data analysis. Semiparametric NLMEs (SNMMs) have been proposed as an extension of NLMEs. These models are a good compromise and retain nice features of both parametric and nonparametric models resulting in more flexible models than standard parametric NLMEs. However, SNMMs are complex models for which estimation still remains a challenge. Previous estimation procedures are based on a combination of log-likelihood approximation methods for parametric estimation and smoothing splines techniques for nonparametric estimation. In this work, we propose new estimation strategies in SNMMs. On the one hand, we use the Stochastic Approximation version of EM algorithm (SAEM) to obtain exact ML and REML estimates of the fixed effects and variance components. On the other hand, we propose a LASSO-type method to estimate the unknown nonlinear function. We derive oracle inequalities for this nonparametric estimator. We combine the two approaches in a general estimation procedure that we illustrate with simulations and through the analysis of a real data set of price evolution in on-line auctions.