Revisiting Precision and Recall Definition for Generative Model Evaluation

In this article we revisit the definition of Precision-Recall (PR) curves for generative models proposed by Sajjadi et al. (arXiv:1806.00035). Rather than providing a scalar for generative quality, PR curves distinguish mode-collapse (poor recall) and bad quality (poor precision). We first generalize their formulation to arbitrary measures, hence removing any restriction to finite support. We also expose a bridge between PR curves and type I and type II error rates of likelihood ratio classifiers on the task of discriminating between samples of the two distributions. Building upon this new perspective, we propose a novel algorithm to approximate precision-recall curves, that shares some interesting methodological properties with the hypothesis testing technique from Lopez-Paz et al (arXiv:1610.06545). We demonstrate the interest of the proposed formulation over the original approach on controlled multi-modal datasets.Comment: ICML 201

Text-to-Image Models for Counterfactual Explanations: a Black-Box Approach

This paper addresses the challenge of generating Counterfactual Explanations (CEs), involving the identification and modification of the fewest necessary features to alter a classifier's prediction for a given image. Our proposed method, Text-to-Image Models for Counterfactual Explanations (TIME), is a black-box counterfactual technique based on distillation. Unlike previous methods, this approach requires solely the image and its prediction, omitting the need for the classifier's structure, parameters, or gradients. Before generating the counterfactuals, TIME introduces two distinct biases into Stable Diffusion in the form of textual embeddings: the context bias, associated with the image's structure, and the class bias, linked to class-specific features learned by the target classifier. After learning these biases, we find the optimal latent code applying the classifier's predicted class token and regenerate the image using the target embedding as conditioning, producing the counterfactual explanation. Extensive empirical studies validate that TIME can generate explanations of comparable effectiveness even when operating within a black-box setting.Comment: WACV 2024 Camera ready + supplementary materia

Generating Private Data Surrogates for Vision Related Tasks

International audienceWith the widespread application of deep networks in industry, membership inference attacks, i.e. the ability to discern training data from a model, become more and more problematic for data privacy. Recent work suggests that generative networks may be robust against membership attacks. In this work, we build on this observation, offering a general-purpose solution to the membership privacy problem. As the primary contribution, we demonstrate how to construct surrogate datasets, using images from GAN generators, labelled with a classifier trained on the private dataset. Next, we show this surrogate data can further be used for a variety of downstream tasks (here classification and regression), while being resistant to membership attacks. We study a variety of different GANs proposed in the literature, concluding that higher quality GANs result in better surrogate data with respect to the task at hand

n-MeRCI: A new Metric to Evaluate the Correlation Between Predictive Uncertainty and True Error

International audienceAs deep learning applications are becoming more and more pervasive in robotics, the question of evaluating the reliability of inferences becomes a central question in the robotics community. This domain, known as predictive uncertainty, has come under the scrutiny of research groups developing Bayesian approaches adapted to deep learning such as Monte Carlo Dropout. Unfortunately, for the time being, the real goal of predictive uncertainty has been swept under the rug. Indeed, these approaches are solely evaluated in terms of raw performance of the network prediction, while the quality of their estimated uncertainty is not assessed. Evaluating such uncertainty prediction quality is especially important in robotics, as actions shall depend on the confidence in perceived information. In this context, the main contribution of this article is to propose a novel metric that is adapted to the evaluation of relative uncertainty assessment and directly applicable to regression with deep neural networks. To experimentally validate this metric, we evaluate it on a toy dataset and then apply it to the task of monocular depth estimation

SiF4 anomalous behaviour reassessed

The Si 1s−1, Si 2s−1, and Si 2p−1 photoelectron spectra of the SiX4 molecules with X = F, Cl, Br, CH3 were measured. From these spectra the Si 1s−1 and Si 2s−1 lifetime broadenings were determined, revealing a significantly larger value for the Si 2s−1 core hole of SiF4 than for the same core hole of the other molecules of the sequence. This finding is in line with the results of the Si 2p−1 core holes of a number of SiX4 molecules, with an exceptionally large broadening for SiF4. For the Si 2s−1 core hole of SiF4 the difference to the other SiX4 molecules can be explained in terms of Interatomic Coulomb Decay (ICD)-like processes. For the Si 2p−1 core hole of SiF4 the estimated values for the sum of the Intraatomic Auger Electron Decay (IAED) and ICD-like processes are too small to explain the observed linewidth. However, the results of the given discussion render for SiF4 significant contributions from Electron Transfer Mediated Decay (ETMD)-like processes at least plausible. On the grounds of our results, some more molecular systems in which similar processes can be observed are identified

Une méta-analyse qualitative de la littérature sur les déterminants de l'adoption de l'activity-based costing

In this paper, we implement a meta-analysis of the literature on the determinants of the adoption of Activity-Based Costing. Our corpus includes 43 papers published in scientific journals. The analysis of this corpus shows the following results. The number of ABC adoption determinants studied is very high, but the average number of estimations of the effect of each of them is low. A very heterogeneous set of statistical methods and proxies has been used. Results on the effect of each determinant on the adoption of ABC are not converging. Our results of the implementation of the vote-counting method to seven of the most commonly estimated determinants show that it is impossible to conclude on a generalized statistically significant relationship, except for top management/champion support. The study of eight moderators shows almost no effect on the relationship between determinants and ABC adoption

Electrochemical Method for Direct Deposition of Nanometric Bismuth and Its Electrochemical Properties vs Li

We report that nanometric bismuth can directly be electrodeposited at room temperature without the use of a nanoporous template. The morphology, microstructure, and purity of the as-prepared electrodeposits were characterized by scanning electron microscopy, transmission electron microscopy, and infrared spectroscopy. Typically, well-crystallized nanometer-sized particles of Bi ranging from 10 to 20 nm are obtained. The key to success of such a process lies in the electrochemical coreduction of pyrocatechol violet during the bismuth deposition, which disturbs the electrocrystallization process. As a first possible application, we show that Bi/Cu nanoarchitectured electrodes exhibit interesting rate capabilities when used as electrode material vs Li

Les occupations Michelsberg et Munzingen d’Ergersheim (Bas-Rhin) « Abbaye » dans leur contexte chrono-culturel

Le site d’Ergersheim (Bas-Rhin) « Abbaye » se trouve à une vingtaine de kilomètres à l’ouest de Strasbourg, en rive gauche de la Bruche. Une opération préventive menée en 2011 y a mis au jour une dizaine de structures domestiques du Néolithique récent. Un gobelet isolé évoque le Michelsberg ancien, tandis que l’essentiel de la céramique se rapporte à la culture de Munzingen (3900-3600 av. J.-C.). L’une de ces fosses accueillait un dépôt funéraire double et simultané. Les observations de terrain suggèrent une décomposition avancée ou complète en espace vide, suivie du prélèvement d’importants segments anatomiques. Un tel cas de figure est rare dans la région, sans toutefois être unique. Enfin, une mandibule de loup faisait partie du dépôt.The “Abbaye” site in Ergersheim (France, Bas-Rhin) is located on the west bank of the river Bruche, twenty kilometres west of Strasbourg. In 2011, a rescue excavation was made of a dozen pits in which Jungneolithikum pottery was found. While one single isolated tulip beaker can be dated to the early Michelsberg culture, most of the collection belongs to the Munzingen culture (3900-3600 BC). In one of those pits, a double and simultaneous funerary deposit was found. Field anthropologists deduced that the decomposition process occurred in an unfilled space, followed by the removal of significant body parts while the decomposition process was at an advanced or terminal stage. Such an act is rare in the area, but not unique. A wolf mandible was part of the same funerary deposit.Der Fundplatz „Abbaye“ in Ergersheim (Departement Bas-Rhin) liegt an die 20 km westlich von Straßburg am linken Ufer der Bruche. Bei einer Präventivgrabung wurden hier 2011 an die 10 jungneolithische Siedlungsstrukturen freigelegt. Ein einzelner Becher erinnert an Früh-Michelsberg, während die Keramik überwiegend Munzingen zugeordnet wird (3900-3600 v. Chr.). Eine der Gruben barg zwei gleichzeitig niedergelegte Leichendepots. Die Beobachtungen legen eine fortgeschrittene oder vollständige Verwesung in einem Hohlraum nahe, gefolgt von der Entnahme anatomischer Segmente. Obwohl solche Fälle in der Region selten sind, handelt es sich nicht um einen Einzelfall. Außerdem barg dieses Depot den Unterkiefer eines Wolfs