Optimal iterative thresholding algorithms improve upon hard and soft thresholding.
problem Optimizing sparsity or rank constraints in optimization problems.
method Developed the notion of relative concavity for thresholding operators, finding a new class of operators that are optimal.
result A new class of thresholding operators, including ℓq thresholding and reciprocal thresholding, achieves the strongest convergence guarantee. Paper proposes a method to identify optimal threshold for stock market networks.
problem Challenges in identifying the optimal threshold for reliable stock network construction.
method Dynamic consistence between threshold network and stock market, optimal threshold maximized by consistence function.
result Optimal threshold value of 0.28 for stocks in S&P 500 Index.
Optimality of threshold strategies proven for Lévy models with discounting.
problem Proving optimality of threshold strategies in Lévy models with discounting.
method Average problem approach to prove optimality of threshold strategies for Lévy models with continuous additive functional discounting.
result Simpler and neater proofs for qualitative properties of optimal thresholds in recursive optimal stopping problems.
LSA minimizes aggregate regret in thresholding bandit with optimal performance.
problem Finding arms with mean rewards above a threshold within a fixed budget.
method LSA, a simple and anytime algorithm aiming to minimize aggregate regret.
result LSA is instance-wise asymptotically optimal in minimizing aggregate regret.
Optimal method detects jumps in jump-diffusion processes.
problem Detecting jumps in jump-diffusion processes with improved finite-sample performance.
method Iterative threshold-kernel method to optimally select threshold parameter.
result Approximate optimal threshold depends on spot volatility, jump intensity, and jump density.
Optimizes search times by resetting agents when a threshold is reached.
problem Improving search efficiency in systems with thresholds.
method Develops a framework for correlated stochastic processes with threshold resetting.
result Optimal resetting can prevent larger losses and is applicable to various stochastic systems.
New method trains neural networks with threshold activation functions efficiently.
problem Training neural networks with threshold activation functions is challenging due to zero gradients.
method We study weight decay regularized training problems of deep neural networks with threshold activations, showing they can be formulated as convex optimization problems.
result Regularized deep threshold network training problems can be formulated as standard convex optimization problems, paralleling the LASSO method.
Optimizes waiting thresholds for node health states in Azure.
problem Minimizing downtime when nodes transition to unhealthy states.
method Customized organic recovery model using node features and gradient descent.
result Optimal thresholds can be found for multiple states in a state machine.
A fast Bayesian optimization method using threshold-guided marginal likelihood maximization.
problem Efficiently optimizing models with Gaussian process regression.
method Guided marginal likelihood maximization with a pre-defined threshold to reduce model selection steps.
result Significantly reduces execution time without compromising optimization quality.
The paper considers an investment timing problem appearing in real options theory. Present values from an investment project are modeled by general diffusion process. We prove necessary and sufficient conditions under which an optimal investment time is induced by threshold strategy. We study also the conditions of opt…
Optimizes threshold selection for variance estimation in financial models.
problem Estimating integrated variance in financial models with jumps.
method Optimizes threshold selection using mean and conditional mean square error criteria.
result Proposes a novel method to approximate the optimal threshold.
Noise makes learning linear thresholds hard, but algorithms can still learn near-optimal thresholds.
problem Learning linear thresholds in noisy data.
method Exploiting natural assumptions on data-generating process.
result Efficient learning of near-optimal linear thresholds is still possible with small data even in the presence of noise.
Optimal thresholds ensure curves remain embedded in flows.
problem Preserving the embeddedness of elastic flows of curves.
method Variational characterization and minimization of bending energy.
result Optimal thresholds for preserving embeddedness are found.
Optimal threshold resetting reduces search time for multiple diffusive searchers.
problem Optimizing search time for multiple diffusive searchers in a one-dimensional space.
method Threshold resetting (TR) is introduced as an event-driven optimization strategy, coupling resetting to the internal dynamics of searchers.
result Optimal threshold distance u significantly reduces mean first-passage time for N≥2 searchers, with a minimum at Nopt(u). Paper develops DLTF to learn optimized dictionaries for efficient thresholded feature recovery.
problem Efficiently recover sparse code support from time-consuming sparse coding.
method Formulates DLTF model to learn optimized dictionary for thresholded feature, derives log-linear time proximal operator.
result DLTF model demonstrates remarkable efficiency, effectiveness, and robustness in various tasks.
Optimal algorithm for identifying best arm in stochastic linear bandits with fixed confidence.
problem Identifying the best arm in stochastic linear bandits with fixed confidence.
method Extending an algorithm designed for Best Arm Identification to the ε-Thresholding Bandit Problem (TBP). result Asymptotically optimal algorithm for TBP.
New RGraSP framework for efficient non-convex optimization.
problem Large-scale non-convex sparsity-constrained optimization problems.
method Relaxed gradient support pursuit with semi-stochastic gradient hard thresholding.
result Our algorithms converge faster with lower per-iteration cost.
A RL algorithm learns optimal multi-threshold policies for MDPs.
problem Overcoming the curse of dimensionality in MDPs.
method Structure-aware RL algorithm exploiting multi-threshold optimal policies.
result The algorithm converges to the optimal policy asymptotically.
This study optimizes multi-modal learning thresholds and algorithms in high dimensions.
problem Optimizing multi-modal learning performance in high-dimensional data.
method Analytical quantification and derivation of AMP algorithm with state evolution analysis.
result Bayes-optimal performance and recovery thresholds derived for multi-modal data.
Iterative shrinkage/thresholding algorithm (ISTA) is a well-studied method for finding sparse solutions to ill-posed inverse problems. In this letter, we present a data-driven scheme for learning optimal thresholding functions for ISTA. The proposed scheme is obtained by relating iterations of ISTA to layers of a simpl…
Study uses SGD to learn optimal thresholds for buying and selling stocks.
problem Optimizing investment strategies in fluctuating stock prices.
method Applying Kiefer--Wolfowitz Stochastic Gradient method to threshold strategies.
result Algorithm converges to log-optimal solution for threshold strategies.
Paper finds a fast method for a matrix norm proximal operator.
problem Optimizing mixed ℓ1,∞ matrix norms efficiently. method Closed-form computation using soft-thresholding, iterative algorithm for thresholds.
result Mixed ℓ1,∞ prox can be computed in closed form. Automatically tunes distance threshold in metric learning.
problem Manual tuning of distance threshold in ITML-based methods is sensitive and time-consuming.
method Optimized metric learning algorithm using Dykstra algorithm to solve nonlinear equation efficiently.
result The proposed metric learning algorithm automatically tunes the distance threshold and achieves comparable accuracy.
STAT-SVD method reduces high-dimensional data sparsity, achieving optimal estimation.
problem Sparse tensor singular value decomposition for high-dimensional data.
method STAT-SVD method with double projection & thresholding scheme.
result STAT-SVD provides sharp thresholding criterion and minimax rate-optimal estimation.
Optimal purchasing policy for mean-reverting items with a finite deadline.
problem Minimizing cost of purchasing and holding mean-reverting items within a fixed time.
method Proved optimal policy as a time-variant threshold function, constructed with dynamic programming.
result Explicit equations for crossing time probability and overshoot expectation.
Investing in declining tech boosts profits, study finds.
problem Optimal decision-making in declining profit streams.
method Modeling profit stream as Brownian motion with negative drift, analyzing thresholds for investment and exit.
result Investment threshold decreases in volatility when profit boost is large.
Sparse reconstruction approaches using the re-weighted l1-penalty have been shown, both empirically and theoretically, to provide a significant improvement in recovering sparse signals in comparison to the l1-relaxation. However, numerical optimization of such penalties involves solving problems with l1-norms in the ob…
Investment and consumption models show a threshold for optimal policies that converge to a steady state.
problem Optimal investment and consumption policies in financial models.
method Analytical and numerical methods to find and validate the turnpike property and convergence rate.
result Threshold value determines the turnpike property for investment policies, independent of specific utility functions.
LinearAPT optimizes decision-making under resource constraints for a linear threshold problem.
problem Optimizing sequential decisions with a linear threshold under resource limitations.
method LinearAPT, an adaptive algorithm for fixed-budget TLB problem.
result LinearAPT achieves theoretical upper bounds and robust performance on various datasets.
Study analyzes FIT schemes under market and regulatory uncertainty.
problem Tackles uncertainty in feed-in tariffs and their impact on investment thresholds.
method Uses semi-analytical real options framework to model and compare FIT schemes.
result Increasing regulatory uncertainty lowers investment thresholds for FIT schemes.
Optimizes SSVEP-based BCI performance by automating threshold selection.
problem Improving classification accuracy of SSVEP-based brain-computer interfaces.
method Formalizes ITR maximization, derives a general formula, and automates threshold selection.
result Achieved ITR of 62 bit/min, outperforming previous methods by a factor of 2.
New RL algorithm learns optimal policies for MDPs using known structure.
problem Overcoming curse of dimensionality and modeling in MDPs.
method Structure-aware online learning algorithm exploiting known threshold policy.
result Proposed algorithm converges to optimal policy with significant speed improvements.
Paper improves gas species identification in complex mixtures using neural networks.
problem Identifying gas species in multi-gas mixtures with high accuracy.
method Multi-label neural networks with optimal thresholding for IR spectroscopy.
result Optimal thresholding improves classification performance over conventional methods.
Paper proves fair classification can be done via simple thresholding.
problem Achieving fair binary classification subject to group fairness constraints.
method Proves Bayes optimal fair learning rule is a group-wise thresholding rule over the Bayes regressor with randomization.
result Proposes an efficient unconstrained optimization algorithm for post-processing fair classification.
MTSSL optimizes threshold τ for better semi-supervised learning performance.
problem Optimizing the threshold τ for effective semi-supervised learning.
method Meta-Thresholding approach to optimize τ during training.
result Optimal values of τ are not necessary for achieving similar performance.
New algorithm resists contamination in high-dimensional regression with optimal performance.
problem Adversarial and measurement errors in high-dimensional data.
method Adversarial Contamination-resistant Iterative Hard Thresholding (AC-IHT) algorithm.
result Achieves minimax near-optimal estimation and signal-adaptive support recovery.
We consider the problem of the optimal trading strategy in the presence of linear costs, and with a strict cap on the allowed position in the market. Using Bellman's backward recursion method, we show that the optimal strategy is to switch between the maximum allowed long position and the maximum allowed short position…
Optimizes risk assessment tools using mixed-integer programming.
problem Challenges in healthcare risk assessment due to label scarcity and asymmetric misclassification costs.
method Jointly optimizes scoring weights and category thresholds via mixed-integer programming (MIP).
result Prevents label-scarce category collapse and achieves more accurate risk categorization.
Study lenient regret and good-action identification in Gaussian process bandits.
problem Optimizing function values above a certain threshold in Gaussian process bandits.
method Study lenient regret notions and introduce algorithms for finding good actions.
result Upper and lower bounds on lenient regret for GP-UCB and elimination algorithms.
Iterative thresholding algorithms are well-suited for high-dimensional problems in sparse recovery and compressive sensing. The performance of this class of algorithms depends heavily on the tuning of certain threshold parameters. In particular, both the final reconstruction error and the convergence rate of the algori…
PCA can detect a low-rank signal in spiked random matrix models, but not always optimally.
problem Understanding when PCA can detect a low-rank signal in the presence of noise.
method Le Cam's notion of contiguity, analysis of spiked Wishart ensemble, and non-spectral tests.
result PCA is sub-optimal for detection in non-Gaussian Wigner ensembles and certain negative spikes in Gaussian Wishart ensemble.
A new method for optimizing non-decomposable metrics with constraints.
problem Optimizing complex machine learning objectives with thresholded constraints.
method Formulate rate-constrained optimization using the Implicit Function theorem and solve with gradient-based methods.
result Demonstrated effectiveness over existing methods on benchmark datasets.
Improved iterative hard thresholding for faster, sparser solutions.
problem Finding sparser solutions without sacrificing runtime.
method Adaptive regularization framework applied to iterative hard thresholding.
result Returns solutions with sparsity O(sκ), improving over existing methods. A learning-based algorithm optimizes admission control in a queuing system.
problem Optimizing admission decisions in a queuing system with unknown parameters.
method Proposes a learning-based dispatching algorithm to minimize regret compared to optimal policies.
result Achieves optimal regret bounds for different scenarios of unknown parameters.
The MBO scheme for data clustering is analyzed in the large data limit, proving convergence to optimal partition problems.
problem Analyzing the MBO scheme for data clustering in the large data limit.
method Implicit gradient descent on the thresholding energy of a similarity graph.
result The MBO scheme outcomes converge to minimizers of a weighted optimal partition problem.
New method simplifies Graphical Lasso for chordal graphs.
problem Sparse covariance estimation for large graphs.
method Closed-form solution for chordal graphs, reducing GL to matrix completion.
result Graphical Lasso and thresholding equivalence holds for chordal structures.
New method for robust regression with near-optimal performance even with high corruption rates.
problem Robust linear regression with response variable corruptions.
method Adaptive hard thresholding for consistent estimation.
result Near-optimal consistent estimation of the true regression vector with 1−o(1) fraction of corruptions. Optimal stopping strategy for a Lévy process near its supremum.
problem Predicting optimal stopping distance for a Lévy process.
method Characterization using scale functions and threshold analysis.
result Non-trivial stopping strategy based on a threshold.