The study proposes algorithms to minimize rating discordance in missing data.
problem Missing ratings in combined rating lists.
method Optimization models and algorithms that minimize total rating discordance.
result The proposed methods outperform state-of-the-art imputation methods in accuracy.
Framework integrates financial and annual report data for better corporate credit ratings.
problem Lack of insights from non-financial data in credit rating models.
method Uses FinBERT to extract features from annual reports and combines them with financial data.
result Improves credit rating accuracy by 8-12%.
A non-trivial probability structure is evident in the binary data extracted from the up/down price movements of very high frequency data such as tick-by-tick data for USD/JPY. In this paper, we analyze the Sony bank USD/JPY rates, ignoring the small deviations from the market price. We then show there is a similar non-…
Active data collection improves convergence rates in operator learning.
problem Improving convergence rates in operator learning with linear target and stochastic input.
method Active data collection strategies with mean-zero stochastic process and continuous covariance kernels.
result Achieves arbitrarily fast error convergence rates with eigenvalue decay of covariance kernels.
This research examines how the error rate of nearest neighbor classifiers varies with dataset size.
problem The scaling of classification error rates with dataset size is not uniform.
method Theoretical analysis of nearest neighbor classifiers, focusing on early and late phases of dataset size.
result The error rate of nearest neighbor classifiers can have fine-grained rates depending on the dataset size and data distribution.
Smartphones can estimate heart rate from other sensor data.
problem Gaps in heart rate data from wearable sensors.
method Regression, SVM, and random forest algorithms to estimate heart rate from smartphone data.
result Smartphone data can improve heart rate estimation from wearable sensors.
IUS framework predicts EUR/USD exchange rate with improved accuracy.
problem Accurate forecasting of EUR/USD exchange rate.
method Combines large language models for sentiment analysis, deep learning for forecasting, and feature selection.
result Optuna-optimized Bi-LSTM model reduces MAE and RMSE by 10.69% and 9.56% respectively.
This paper uses LLMs to improve equity stock ratings by ingesting diverse financial and news data.
problem Challenges in traditional stock rating methods, including data overload, inconsistencies, and delayed reactions.
method Application of LLMs to generate multi-horizon stock ratings using various datasets.
result LLMs enhance the accuracy and consistency of stock ratings, outperforming traditional methods in forward returns.
The paper explores using set-level ratings for better user-item preference prediction in recommender systems.
problem Capturing user preferences on individual items using set-level ratings.
method Developed collaborative filtering-based methods to model user behaviors in set-level ratings.
result Collaborative filtering-based models can recover and predict user preferences on individual items using set-level ratings.
CCR-CNN uses CNN to predict corporate credit ratings from financial data.
problem Lack of data and limited model performance in predicting corporate credit ratings.
method Transform corporations into images and use CNN to analyze complex feature interactions.
result CCR-CNN outperforms state-of-the-art methods in predicting corporate credit ratings.
The paper finds active learning is helpful when it reduces error rate.
problem Understanding when active learning improves model performance.
method Empirical study on 21 datasets with logistic regression and uncertainty sampling.
result There is a strong inverse correlation between data efficiency and error rate.
Paper studies CLT rates for dependent data in Wasserstein-p distance.
problem CLT rates for multivariate dependent data in Wasserstein-p distance.
method Analyzes locally dependent sequences and geometrically ergodic Markov chains.
result Establishes optimal W1 CLT rates and Wp (p≥2) rates for dependent data. The paper models rating transitions and calibrates them to market data for XVA calculations.
problem Calibrating rating models to both historical and market data for accurate XVA calculations.
method Modeling rating transitions as a Markov chain, calibrating to historical and market data, proposing a novel calibration procedure.
result Improved XVA scheme through better calibration of rating models.
New method uses data perturbation for loss minimization with theoretical guarantees.
problem Data privacy and irrecoverability.
method Regularized loss minimization with local data perturbation.
result Theoretical guarantees of generalization and convergence rates with perturbed data.
Model captures both slow and fast time variations in financial data.
problem Analyzing high-frequency financial data with varying background rates.
method Developed a Hawkes process with a time-varying background rate using Bayesian estimation.
result Model significantly improves goodness-of-fit to financial data, especially during fluctuating background rates.
We calibrate and test various variants of field theory models of the interest rate with data from eurodollars futures. A model based on a simple psychological factor are seen to provide the best fit to the market. We make a model independent determination of the volatility function of the forward rates from market data…
Estimates rate-distortion function for large datasets using neural networks.
problem Designing lossy data compression schemes and comparing them with theoretical limits.
method Re-formulate rate-distortion objective and solve using neural networks.
result NERD accurately estimates the rate-distortion function for real-world datasets.
Rate-In dynamically adjusts dropout rates during inference to improve uncertainty estimation in neural networks.
problem Static dropout rates lead to suboptimal uncertainty estimates in neural networks.
method Rate-In dynamically adjusts dropout rates using information-theoretic principles.
result Rate-In improves calibration and sharpens uncertainty estimates compared to fixed or heuristic dropout rates.
Exact risk and learning rate curves derived for adaptive SGD on high-dimensional problems.
problem Analyzing risk and learning rate dynamics in high-dimensional optimization problems.
method Developed a framework to give exact expressions for risk and learning rate curves using ODEs.
result Exact expressions for risk and learning rate curves, with detailed analysis of two adaptive learning rates.
Paper analyzes deep learning models for credit rating prediction using text and numerical data.
problem Improving credit rating prediction using multi-modal deep learning.
method Testing different deep learning models and fusion strategies for structured and unstructured datasets.
result CNN-based multi-modal model with two fusion strategies outperformed other models.
Study shows deep linear networks can converge to flatter minima at large learning rates.
problem Understanding the implicit bias of deep linear networks at large learning rates.
method Characterization of deep linear networks for binary classification using logistic loss in the large learning rate regime.
result Gradient descent iterates converge to a flatter minimum in the catapult phase for certain data separation conditions.
We first show that there are in fact triangular arbitrage opportunities in the spot foreign exchange markets, analyzing the time dependence of the yen-dollar rate, the dollar-euro rate and the yen-euro rate. Next, we propose a model of foreign exchange rates with an interaction. The model includes effects of triangular…
Proposes a new Lasso method for high missing rate data.
problem Handling high-dimensional data with many missing values.
method Integrates mean imputed covariance to overcome estimation bias.
result Effective even with high missing rates, improving upon CoCoLasso.
Rating prediction is an important application, and a popular research topic in collaborative filtering. However, both the validity of learning algorithms, and the validity of standard testing procedures rest on the assumption that missing ratings are missing at random (MAR). In this paper we present the results of a us…
Two methods estimate rating transition probabilities, one Markov, one non-Markov, differing in default probabilities.
problem Estimating rating transition probabilities and default probabilities accurately.
method Markov and non-Markov frameworks, Fisher information matrix, self-exciting marked point processes.
result Non-Markov model yields higher default probabilities in investment grades, lower in speculative grades.
Crowdsourcing is an effective tool for human-powered computation on many tasks challenging for computers. In this paper, we provide finite-sample exponential bounds on the error rate (in probability and in expectation) of hyperplane binary labeling rules under the Dawid-Skene crowdsourcing model. The bounds can be appl…
AdaOja improves Oja's algorithm for streaming PCA with adaptive learning rates.
problem Lack of standardized learning rates in Oja's algorithm for streaming PCA.
method Proposes AdaOja, a novel learning rate scheme for Oja's method.
result AdaOja outperforms common learning rate choices and performs comparably to state-of-the-art algorithms.
Data interpolation can achieve optimal rates in nonparametric regression and prediction.
problem Achieving optimal rates in nonparametric regression and prediction.
method Interpolating the training data to achieve optimal rates.
result Interpolating the training data can achieve optimal rates for nonparametric regression and prediction.
We introduce an autoregressive-type model with self-modulation effects for a foreign exchange rate by separating the foreign exchange rate into a moving average rate and an uncorrelated noise. From this model we indicate that traders are mainly using strategies with weighted feedbacks of the past rates in the exchange …
Study expands multiclass classification models with new rates and partial concept classes.
problem Multiclass classification with a bounded number of labels under various conditions.
method Extends traditional PAC model to distribution-dependent and data-dependent learning rates, characterizes optimal rates for universal and partial concept classes.
result Characterizes three types of learning rates (exponential, linear, arbitrarily slow) for fixed distributions and complexity measures for partial concept classes.
We prove new fast learning rates for the one-vs-all multiclass plug-in classifiers trained either from exponentially strongly mixing data or from data generated by a converging drifting distribution. These are two typical scenarios where training data are not iid. The learning rates are obtained under a multiclass vers…
MOB-dS uses permutation to correct for dependency in discrete survival data.
problem Identifying subgroups in discrete event time data with potential spurious results.
method Model-based recursive partitioning (MOB) with modified data matrix and permutation test.
result MOB-dS controls type I error rate better than standard MOB for discrete survival data.
Analyzes Indian commercial dynamism using time series data.
problem Understanding commercial dynamism in India.
method Time series analysis of various economic indicators.
result Detailed insights into growth rate, trade balance, etc.
Paper improves classification rates for private data.
problem Classifying data with privacy constraints and relaxed assumptions.
method Introduced a novel approach for classification under privacy constraints, relaxing the strong density assumption.
result Achieved minimax optimal convergence rates without strong density assumption.
New research shows unlabeled data is equally valuable as labeled data in certain semi-supervised learning scenarios.
problem Improving learning performance with limited labeled data.
method Statistical models with continuous parameters, showing equal utility of unlabeled data under specific conditions.
result The learning rate of semi-supervised learning scales similarly to supervised learning when unlabeled data is abundant.
Study examines how data augmentation impacts optimization in linear regression.
problem Understanding how data augmentation schedules affect optimization in linear regression.
method Analyzed the effect of augmentation on optimization in linear regression with MSE loss, using classical convex optimization and recent work on implicit bias.
result Proved that under certain joint schedules for learning rate and augmentation scheme, augmented gradient descent converges and characterized the resulting minimum.
Paper analyzes faster convergence rates for reinforcement learning from offline data.
problem Analyzing faster convergence rates for reinforcement learning from offline data.
method Fine analysis of reinforcement learning from offline data, providing fast rates for regret convergence.
result The paper provides fast rates for the regret convergence, showing that the level of exponentiation depends on the noise in the decision-making problem.
A new model reduces rating transition matrix estimation errors for small portfolios.
problem Estimating rating transition matrices for small portfolios leads to unreliable and unstable predictions.
method A sparse structural model with three parameters that assumes an autoregressive mean-reverting ability-to-pay process.
result The model produces well-behaved transition probabilities, reducing statistical degrees of freedom and improving reliability.
Entropy rate of sequential data-streams naturally quantifies the complexity of the generative process. Thus entropy rate fluctuations could be used as a tool to recognize dynamical perturbations in signal sources, and could potentially be carried out without explicit background noise characterization. However, state of…
In this paper, we investigate the statistical convergence rate of a Bayesian low-rank tensor estimator. Our problem setting is the regression problem where a tensor structure underlying the data is estimated. This problem setting occurs in many practical applications, such as collaborative filtering, multi-task learnin…
Paper proposes a distributed method to estimate principal eigenvector from high-rate streaming data.
problem Estimating principal eigenvector from high streaming data rate.
method Distributed Krasulina (D-Krasulina) and mini-batch extension (DM-Krasulina) methods.
result Achieves optimal estimation error rates under high streaming conditions.
Large learning rates cause oscillations in NN weights that improve generalization.
problem Improving generalization of neural networks trained with large learning rates.
method Theoretical analysis and feature-noise data generation model.
result Oscillating SGD with large learning rates benefits NN generalization by effectively learning weak features.
New guarantees for ERM with adaptively collected data.
problem Failure of ERM guarantees with adaptively collected data.
method Importance sampling weighted ERM algorithm with maximal inequality.
result First generalization guarantees and fast convergence rates for adaptively collected data.
SGD converges to zero loss for separable data with fixed learning rate.
problem Optimizing homogeneous linear classifiers with SGD on linearly separable data.
method Proved convergence of SGD with fixed learning rate for separable data.
result SGD converges to zero loss for separable data with fixed learning rate.
Classifies and clusters event time data using non-homogeneous Poisson process models.
problem Classifying and clustering event time data from multiple observations.
method Modeling rate functions using spline basis expansion, estimating coefficients using maximum likelihood, and assigning observations to groups based on likelihood.
result The classification and clustering approaches perform well on both synthetic and real-world data.
Efficiently estimates Weingarten maps and curvatures from manifold data.
problem Estimating Weingarten maps and curvatures from manifold data.
method Statistical model for Weingarten map estimation; convergence rate analysis.
result Convergence rate of the estimator as sample size increases.
Two privacy-preserving rating collection methods for recommender systems.
problem Collecting user ratings while maintaining privacy.
method Modified Laplace mechanism and randomized response.
result Both mechanisms are differentially private and preserve data utility.
New algorithms for learning from sensor data in networks with limited communication.
problem Learning from high-rate data streams in networked systems with limited communication.
method Distributed stochastic approximation mirror descent (D-SAMD) and accelerated distributed stochastic approximation mirror descent (AD-SAMD) algorithms.
result Order-optimum convergence of distributed learning schemes even with small communication rates in well-connected networks.