Research
On-device research index

arXiv research

A locally-built, LLM-digested index of recent arXiv papers in quant finance, geometry/topology, and statistical ML — keyword search served straight from SQLite on this machine.

168,657 papers · 148 categories

Trend · papers per month

4998147196 · Jun 202019922001200920172026
48 results for improper priors

Bayesian evidence computation revisited for model selection with improper priors.

problem Model selection with improper priors and their impact on Bayesian evidence computation.
method Employing improper priors in model selection problems, distinguishing between Bayesian evidence and fake evidences.
result Diffuse priors asymptotically to infinity do not recover the area under the likelihood.

Proposes a new SPVM model for RVM with more flexible priors.

problem Improper priors on multiple penalty parameters in RVM lead to improper posteriors.
method Introduces a single penalty approach (SPRVM) and a semi-Bayesian fitting method.
result SPRVM allows for more flexible priors and has proven conditions for posterior propriety.

The paper discusses the impact of prior densities on Bayesian model selection.

problem The sensitivity of marginal likelihood to prior choice in Bayesian model selection.
method Analyzes the role of prior densities in model selection, discusses improper priors, and proposes solutions.
result Marginal likelihood can be sensitive to prior choice, but improper priors can still be used with caution.

The study classifies singularities in discrete improper affine spheres.

problem Classifying singularities in discrete improper affine spheres.
method Analysis of discrete improper affine spheres based on asymptotic nets, distinguishing singular edges and vertices.
result First step in classifying singularities of discrete nets.

In this paper we consider convex improper affine maps of the 3-dimensional affine space and classify their singularities. The main tool developed is a generating family with properties that closely resembles the area function for non-convex improper affine maps.

2012-04-17abs ↗pdf ↗

Dropout, a stochastic regularisation technique for training of neural networks, has recently been reinterpreted as a specific type of approximate inference algorithm for Bayesian neural networks. The main contribution of the reinterpretation is in providing a theoretical framework useful for analysing and extending the…

2018-07-05abs ↗pdf ↗

We construct a new representation formula for indefinite improper affine spheres in terms of two para-holomorphic functions and study singularities which appear in this representation formula. As a result, it follows that cuspidal cross caps never appear as the singularities on indefinite improper affine spheres and so…

2008-01-31abs ↗pdf ↗

The study classifies certain types of incomplete surfaces with low curvature.

problem Classifying incomplete affine spheres with specific curvature constraints.
method Analyzing total curvature and asymptotic behavior of surfaces.
result New examples of incomplete affine spheres with positive genus found.

There are exactly two different types of bi-dimensional improper affine spheres: the non-convex ones can be modeled by the center-chord transform of a pair of planar curves while the convex ones can be modeled by a holomorphic map. In this paper, we show that both constructions can be generalized to arbitrary even dime…

2012-12-19abs ↗pdf ↗

Framework evaluates the impact of prior knowledge in deep learning models.

problem Mitigating data-driven model shortcomings like data dependence and generalization ability.
method Model-agnostic framework inspired by interpretable machine learning, assessing data volume and estimation range effects.
result Complex relationship between data and knowledge, including dependence, synergistic, and substitution effects.

New DEC variant improves sample complexity bounds in decision making.

problem Understanding sample-efficient learning guarantees in decision making.
method Introducing a new Constrained Decision-Estimation Coefficient (DEC) and using it to derive improved lower bounds.
result New lower bounds improve upon prior work in three aspects: expectation, global applicability, and improper reference models.

We give the best possible upper bound for the number of exceptional values of the Lagrangian Gauss map of complete improper affine fronts in the affine three-space. We also obtain the sharp estimate for weakly complete case. As an application of this result, we provide a new and simple proof of the parametric affine Be…

2010-04-09abs ↗pdf ↗

We study the Automatic Relevance Determination procedure applied to deep neural networks. We show that ARD applied to Bayesian DNNs with Gaussian approximate posterior distributions leads to a variational bound similar to that of variational dropout, and in the case of a fixed dropout rate, objectives are exactly the s…

2018-11-01abs ↗pdf ↗

In this paper, we derive a Bayesian model order selection rule by using the exponentially embedded family method, termed Bayesian EEF. Unlike many other Bayesian model selection methods, the Bayesian EEF can use vague proper priors and improper noninformative priors to be objective in the elicitation of parameter prior…

2017-03-30abs ↗pdf ↗

New algorithm reduces online logistic regression regret without exponential constant.

problem Improper learning in online logistic regression with logarithmic regret.
method Regularized empirical risk minimization with surrogate losses.
result Regret scaling as O(B log(Bn)) with low computational complexity.

The area distance to a convex plane curve is an important concept in computer vision. In this paper we describe a strong link between area distances and improper affine spheres. This link makes possible a better understanding of both theories. The concepts of the theory of affine spheres lead to a new definition of an …

2007-10-09abs ↗pdf ↗

Variational dropout (VD) is a generalization of Gaussian dropout, which aims at inferring the posterior of network weights based on a log-uniform prior on them to learn these weights as well as dropout rate simultaneously. The log-uniform prior not only interprets the regularization capacity of Gaussian dropout in netw…

2018-11-19abs ↗pdf ↗

We study the question of learning an adversarially robust predictor. We show that any hypothesis class H\mathcal{H} with finite VC dimension is robustly PAC learnable with an improper learning rule. The requirement of being improper is necessary as we exhibit examples of hypothesis classes H\mathcal{H} with finite VC…

2019-02-12abs ↗pdf ↗

Study shows improper learning can outperform proper learning in misspecified models.

problem Misspecification in probabilistic prediction models.
method Investigates the performance of proper and improper learning strategies in misspecified models.
result Improper learning can achieve lower regret compared to proper learning, especially in high-dimensional settings.

New active learning framework for multiclass classification beyond realizability assumption.

problem Active learning in non-realizable settings with convex model classes.
method Surrogate risk minimization, epoch-based fitting, aggregation of models.
result Achieves label and sample complexity comparable to prior work in non-realizable settings.

Given a Lagrangian submanifold LL of the affine symplectic 2n2n-space, one can canonically and uniquely define a center-chord and a special improper affine sphere of dimension 2n2n, both of whose sets of singularities contain LL. Although these improper affine spheres (IAS) always present other singularities away fro…

2019-06-07abs ↗pdf ↗

We revisit the question of reducing online learning to approximate optimization of the offline problem. In this setting, we give two algorithms with near-optimal performance in the full information setting: they guarantee optimal regret and require only poly-logarithmically many calls to the approximation oracle per it…

2018-04-20abs ↗pdf ↗

Two machine learning models detect anomalies in ER claims, saving up to 40% in improper payments.

problem Improper health insurance payments from fraud and upcoding.
method Two machine learning models: an upcoding model based on severity code distributions and a random forest model for claim sorting.
result Random forest model saved 12% to 40% in improper payments compared to a baseline approach.

Bornological metrics on groups are studied, showing equivalence classes and constructing non-equivalent improper metrics.

problem Characterizing and constructing left-invariant metrics on groups that are not proper.
method Introducing bornological metrics and studying their equivalence classes, constructing non-equivalent improper metrics.
result Each coarse equivalence class of bornological metrics is determined by a bornology, and every class contains a canonical left-invariant representative.

Study shows memory needs grow with task sequence length in continual learning.

problem Challenges in retaining aptitude for multiple learning tasks sequentially.
method Complexity-theoretic study using communication complexity and multiplicative weights update.
result Memory needs grow linearly with task sequence length, suggesting intractability.

Study shows inefficiency of sparse linear regression learning with fewer than Ω(k^2) samples.

problem Efficiency of sparse linear regression learning with minimal samples.
method Reduction to sparse PCA problems and lower bounds.
result Efficient algorithms for sparse linear regression require at least Ω(k^2) samples.

Learning linear predictors with the logistic loss---both in stochastic and online settings---is a fundamental task in machine learning and statistics, with direct connections to classification and boosting. Existing "fast rates" for this setting exhibit exponential dependence on the predictor norm, and Hazan et al. (20…

2018-03-25abs ↗pdf ↗

Efficiently learns complex Boolean functions under Gaussian distributions.

problem Learning complex Boolean functions of halfspaces under Gaussian marginals.
method First efficient proper agnostic learning algorithm for arbitrary Boolean functions of K halfspaces.
result Matches the best known improper learning algorithm's run-time dependence on dimension.

Author presents the second variational formula for statistical biharmonic maps.

problem Developing a formula for statistical biharmonic maps.
method Introduced the second variational formula for the statistical bi-energy functional.
result The second variational formula can be represented using Hessian curvature in Hessian manifolds.

Paper explores rate-preserving reductions between Blackwell approachability and no-regret learning.

problem Tackles rate-preserving reductions between Blackwell approachability and no-regret learning.
method Studies fine-grained reductions and optimal rates of convergence.
result Shows that rate-preserving reductions do not always hold, but provides conditions for when they do.

The paper studies a new class of affine maximal surfaces with singularities.

problem Understanding the properties of affine maximal surfaces with singularities.
method Defining a new subclass of affine maximal surfaces and applying Euclidean minimal surface theory.
result Affine maxfaces satisfy an Osserman-type inequality and do not contain non-trivial improper affine fronts.

The nonzero level sets in nn-dimensional flat affine space of a translationally homogeneous function are improper affine spheres if and only if the Hessian determinant of the function is equal to a nonzero constant multiple of the nnth power of the function. The exponentials of the characteristic polynomials of certa…

2017-07-26abs ↗pdf ↗

We study the problem of learning influence functions under incomplete observations of node activations. Incomplete observations are a major concern as most (online and real-world) social networks are not fully observable. We establish both proper and improper PAC learnability of influence functions under randomly missi…

2016-11-07abs ↗pdf ↗

We present a representation formula for discrete indefinite affine spheres via loop group factorizations. This formula is derived from the Birkhoff decomposition of loop groups associated with discrete indefinite affine spheres. In particular we show that a discrete indefinite improper affine sphere can be constructed …

2020-01-22abs ↗pdf ↗

One-Shot Neural Architecture Search (NAS) is a promising method to significantly reduce search time without any separate training. It can be treated as a Network Compression problem on the architecture parameters from an over-parameterized network. However, there are two issues associated with most one-shot NAS methods…

2019-05-13abs ↗pdf ↗