The Political Economy of Social Change and Nation-Building During the Progressive Era

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Dishonesty in Developing Countries - What Did We Learn From Experiments?

International audienceThis chapter reviews the recent literature on cheating and corruption to demonstrate the value that experimental methods hold for studying dishonesty in developing countries. Emphasizing the diversity of experimental methods, the chapter highlights the contributions of laboratory and field experiments to the measurement of cross-country differences and to the identification of the causes of corruption and cheating. This body of literature has provided evidence of the causal effect of social norms, institutions, group identity, and social status concerns. Moreover, the existing research has also delivered practical policy recommendations to ethics-related development problems

Growth of the sandy isthmus of tyre and ensuing relocation of its harbors

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L’olympisme au secours du Water-Polo

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Random Forest based Qantile Oriented Sensitivity Analysis indices estimation

International audienceWe propose a random forest based estimation procedure for Quantile-Oriented Sensitivity Analysis—QOSA. In order to be efficient, a cross-validation step on the leaf size of trees is required. Our full estimation procedure is tested on both simulated data and a real dataset. Our estimators use either the bootstrap samples or the original sample in the estimation. Also, they are either based on a quantile plug-in procedure (the R-estimators) or on a direct minimization (the Q-estimators). This leads to 8 different estimators which are compared on simulations. From these simulations, it seems that the estimation method based on a direct minimization is better than the one plugging the quantile. This is a significant result because the method with direct minimization requires only one sample and could therefore be preferred

Pointwise and correlation bounds on Dedekind sums over small subgroups

International audienceWe obtain new bounds, pointwisely and on average, for Dedekind sums $\mathsf{s}(λ,p)$ modulo a prime $p$ with $λ$ of small multiplicative order $d$ modulo $p$. Assuming the infinitude of Mersenne primes, the range of our results is optimal. Moreover, we relate high moments of $L(1,χ)$ over subgroups of characters to some correlations of Dedekind sums and use our recent results to study these correlations

A Study on Hierarchical Text Classification as a Seq2seq Task

International audienceWith the progress of generative neural models, Hierarchical Text Classification (HTC) can be cast as a generative task. In this case, given an input text, the model generates the sequence of predicted class labels taken from a label tree of arbitrary width and depth. Treating HTC as a generative task introduces multiple modeling choices. These choices vary from choosing the order for visiting the class tree and therefore defining the order of generating tokens, choosing either to constrain the decoding to labels that respect the previous level predictions, up to choosing the pre-trained Language Model itself. Each HTC model therefore differs from the others from an architectural standpoint, but also from the modeling choices that were made. Prior contributions lack transparent modeling choices and open implementations, hindering the assessment of whether model performance stems from architectural or modeling decisions. For these reasons, we propose with this paper an analysis of the impact of different modeling choices along with common model errors and successes for this task. This analysis is based on an open framework coming along this paper that can facilitate the development of future contributions in the field by providing datasets, metrics, error analysis toolkit and the capability to readily test various modeling choices for one given model

A variational principle for Gaussian lattice sums

62 pages, 11 figures, 81 referencesWe consider a two-dimensional analogue of Jacobi theta functions and prove that, among all lattices $\Lambda \subset \mathbb{R}^2$ with fixed density, the minimal value is maximized by the hexagonal lattice. This result can be interpreted as the dual of a 1988 result of Montgomery who proved that the hexagonal lattice minimizes the maximal values. Our inequality resolves a conjecture of Strohmer and Beaver about the operator norm of a certain type of frame in $L^2(\mathbb{R})$. It has implications for minimal energies of ionic crystals studied by Born, the geometry of completely monotone functions and a connection to the elusive Landau constant

Doubly nonlinear diffusive PDEs: new existence results via generalized Wasserstein gradient flows

We prove an existence result for a large class of PDEs with a nonlinear Wasserstein gradient flow structure. We use the classical theory of Wasserstein gradient flow to derive an EDI formulation of our PDE and prove that under some integrability assumptions on the initial condition the PDE is satisfied in the sense of distributions