arXiv research

This work analyzes two methods for combining multiple binary labels in bipartite ranking.

The study analyzes a model for aggregate losses with dependent and overdispersed inter-losses times.

In classification, the de facto method for aggregating individual losses is the average loss. When the actual metric of interest is 0-1 loss, it is common to minimize the average surrogate loss for some well-behaved (e.g. convex) surrogate. Recently, several other aggregate losses such as the maximal loss and average t…

This paper compares two loss functions for learning from aggregated responses and introduces an interpolating estimator.

New aggregation strategy handles unbounded losses with regret bounds.

Introduces SoRR for aggregating losses in supervised learning.

We formalize how markets aggregate via arbitrage and quantify liquidity loss.

Using Monte Carlo simulation to calculate the Value at Risk (VaR) as a possible risk measure requires adequate techniques. One of these techniques is the application of a compound distribution for the aggregates in a portfolio. In this paper, we consider the aggregated loss of Gamma distributed severities and estimate …

A new method for forming learning objectives using the sum of ranked range.

In this paper, we address the aggregation of dependent stop loss reinsurance risks where the dependence among the ceding insurer(s) risks is governed by the Sarmanov distribution and each individual risk belongs to the class of Erlang mixtures. We investigate the effects of the ceding insurer(s) risk dependencies on th…

Estimation of the operational risk capital under the Loss Distribution Approach requires evaluation of aggregate (compound) loss distributions which is one of the classic problems in risk theory. Closed-form solutions are not available for the distributions typically used in operational risk. However with modern comput…

We address the problem of aggregating an ensemble of predictors with known loss bounds in a semi-supervised binary classification setting, to minimize prediction loss incurred on the unlabeled data. We find the minimax optimal predictions for a very general class of loss functions including all convex and many non-conv…

This paper explores methods for combining predictions in multilabel classification.

Let $\cF$ be a set of $M$ classification procedures with values in $[-1,1]$. Given a loss function, we want to construct a procedure which mimics at the best possible rate the best procedure in $\cF$. This fastest rate is called optimal rate of aggregation. Considering a continuous scale of loss functions with various …

The paper examines how small positive dependence can lead to correlated tail risks.

Label aggregation makes learning robust to noisy labels.

Extends graph similarity theory to improve MPNNs' generalization abilities.

AEW estimator achieves optimal risk in expectation for large enough temperatures.

Study online learning in MDPs with aggregate bandit feedback, achieving low regret in both stochastic and adversarial settings.

The paper introduces a new loss function to prevent overfitting in semi-supervised graph networks.

Algorithm for online decision making with unknown dynamics and aggregate feedback.

In this work, we introduce the {\em average top-$k$} (\atk) loss as a new aggregate loss for supervised learning, which is the average over the $k$ largest individual losses over a training dataset. We show that the \atk loss is a natural generalization of the two widely used aggregate losses, namely the average loss a…

Log-Loss scores expose membership privacy breaches.

In this paper we extend the setting of the online prediction with expert advice to function-valued forecasts. At each step of the online game several experts predict a function, and the learner has to efficiently aggregate these functional forecasts into a single forecast. We adapt basic mixable (and exponentially conc…

This research develops a new model for cyber risk and insurance pricing.

MANA-Net improves market predictions by dynamically weighting news sentiments.

New method improves transductive learning predictions with multiplicative oracle inequalities.

Paper introduces DCoVaR for aggregate risk models, outperforming existing methods.

Mixability of a loss is known to characterise when constant regret bounds are achievable in games of prediction with expert advice through the use of Vovk's aggregating algorithm. We provide a new interpretation of mixability via convex analysis that highlights the role of the Kullback-Leibler divergence in its definit…

New method preserves privacy by aggregating feature-vectors with weighted sums, ensuring label differential privacy.

We introduce a new recursive aggregation procedure called Bernstein Online Aggregation (BOA). The exponential weights include an accuracy term and a second order term that is a proxy of the quadratic variation as in Hazan and Kale (2010). This second term stabilizes the procedure that is optimal in different senses. We…

Aggregated hold-out (Agghoo) is a method which averages learning rules selected by hold-out (that is, cross-validation with a single split). We provide the first theoretical guarantees on Agghoo, ensuring that it can be used safely: Agghoo performs at worst like the hold-out when the risk is convex. The same holds true…

Proposes a new risk model using stable laws to manage company-wide losses.

How, and to what extent, does an interconnected financial system endogenously amplify external shocks? This paper attempts to reconcile some apparently different views emerged after the 2008 crisis regarding the nature and the relevance of contagion in financial networks. We develop a common framework encompassing seve…

The paper compares aggregated data labels in curated and random bags for machine learning models.

New method improves CATE model selection with optimal regret rates.

Adaptive Bayesian learning aggregates experts to improve performance.

This study addresses the issue of predicting the glaucomatous visual field loss from patient disease datasets. Our goal is to accurately predict the progress of the disease in individual patients. As very few measurements are available for each patient, it is difficult to produce good predictors for individuals. A rece…

The goal of online prediction with expert advice is to find a decision strategy which will perform almost as well as the best expert in a given pool of experts, on any sequence of outcomes. This problem has been widely studied and $O(\sqrt{T})$ and $O(\log{T})$ regret bounds can be achieved for convex losses (\cite{zin…

New federated learning algorithms improve model aggregation robustness.

We decompose the squared price-of-risk premium into three components: intervention-stable premium, confounding wedge, and information loss.

We study cross-country GDP losses due to financial crises in terms of frequency (number of loss events per period) and severity (loss per occurrence). We perform the Loss Distribution Approach (LDA) to estimate a multi-country aggregate GDP loss probability density function and the percentiles associated to extreme eve…

PEARL combines multiple representation learning methods to enhance model performance.

We consider the problem of learning convex aggregation of models, that is as good as the best convex aggregation, for the binary classification problem. Working in the stream based active learning setting, where the active learner has to make a decision on-the-fly, if it wants to query for the label of the point curren…

Proposes a probabilistic framework for smart contract risk quantification.

The paper presents a method for generating well-calibrated prediction intervals using quality-driven deep ensembles.

Data aggregation improves HAC for resource-constrained systems.

Regulatory requirements dictate that financial institutions must calculate risk capital (funds that must be retained to cover future losses) at least annually. Procedures for doing this have been well-established for many years, but recent developments in the treatment of conduct risk (the risk of loss due to the relat…