483 research outputs found
Lightweight Estimation of Hand Mesh and Biomechanically Feasible Kinematic Parameters
3D hand pose estimation is a long-standing challenge in both robotics and
computer vision communities due to its implicit depth ambiguity and often
strong self-occlusion. Recently, in addition to the hand skeleton, jointly
estimating hand pose and shape has gained more attraction. State-of-the-art
methods adopt a model-free approach, estimating the vertices of the hand mesh
directly and providing superior accuracy compared to traditional model-based
methods directly regressing the parameters of the parametric hand mesh.
However, with the large number of mesh vertices to estimate, these methods are
often slow in inference. We propose an efficient variation of the previously
proposed image-to-lixel approach to efficiently estimate hand meshes from the
images. Leveraging recent developments in efficient neural architectures, we
significantly reduce the computation complexity without sacrificing the
estimation accuracy. Furthermore, we introduce an inverted kinematic(IK)
network to translate the estimated hand mesh to a biomechanically feasible set
of joint rotation parameters, which is necessary for applications that leverage
pose estimation for controlling robotic hands. Finally, an optional
post-processing module is proposed to refine the rotation and shape parameters
to compensate for the error introduced by the IK net. Our Lite I2L Mesh Net
achieves state-of-the-art joint and mesh estimation accuracy with less than
of the total computational complexity of the original I2L hand mesh
estimator. Adding the IK net and post-optimization modules can improve the
accuracy slightly at a small computation cost, but more importantly, provide
the kinematic parameters required for robotic applications
Robust High-dimensional Tuning Free Multiple Testing
A stylized feature of high-dimensional data is that many variables have heavy
tails, and robust statistical inference is critical for valid large-scale
statistical inference. Yet, the existing developments such as Winsorization,
Huberization and median of means require the bounded second moments and involve
variable-dependent tuning parameters, which hamper their fidelity in
applications to large-scale problems. To liberate these constraints, this paper
revisits the celebrated Hodges-Lehmann (HL) estimator for estimating location
parameters in both the one- and two-sample problems, from a non-asymptotic
perspective. Our study develops Berry-Esseen inequality and Cram\'{e}r type
moderate deviation for the HL estimator based on newly developed non-asymptotic
Bahadur representation, and builds data-driven confidence intervals via a
weighted bootstrap approach. These results allow us to extend the HL estimator
to large-scale studies and propose \emph{tuning-free} and \emph{moment-free}
high-dimensional inference procedures for testing global null and for
large-scale multiple testing with false discovery proportion control. It is
convincingly shown that the resulting tuning-free and moment-free methods
control false discovery proportion at a prescribed level. The simulation
studies lend further support to our developed theory.Comment: In this paper, we develop tuning-free and moment-free high
dimensional inference procedures
Communication-Efficient Distributed Estimation and Inference for Cox's Model
Motivated by multi-center biomedical studies that cannot share individual
data due to privacy and ownership concerns, we develop communication-efficient
iterative distributed algorithms for estimation and inference in the
high-dimensional sparse Cox proportional hazards model. We demonstrate that our
estimator, even with a relatively small number of iterations, achieves the same
convergence rate as the ideal full-sample estimator under very mild conditions.
To construct confidence intervals for linear combinations of high-dimensional
hazard regression coefficients, we introduce a novel debiased method, establish
central limit theorems, and provide consistent variance estimators that yield
asymptotically valid distributed confidence intervals. In addition, we provide
valid and powerful distributed hypothesis tests for any coordinate element
based on a decorrelated score test. We allow time-dependent covariates as well
as censored survival times. Extensive numerical experiments on both simulated
and real data lend further support to our theory and demonstrate that our
communication-efficient distributed estimators, confidence intervals, and
hypothesis tests improve upon alternative methods
Spectral Ranking Inferences based on General Multiway Comparisons
This paper studies the performance of the spectral method in the estimation
and uncertainty quantification of the unobserved preference scores of compared
entities in a very general and more realistic setup in which the comparison
graph consists of hyper-edges of possible heterogeneous sizes and the number of
comparisons can be as low as one for a given hyper-edge. Such a setting is
pervasive in real applications, circumventing the need to specify the graph
randomness and the restrictive homogeneous sampling assumption imposed in the
commonly-used Bradley-Terry-Luce (BTL) or Plackett-Luce (PL) models.
Furthermore, in the scenarios when the BTL or PL models are appropriate, we
unravel the relationship between the spectral estimator and the Maximum
Likelihood Estimator (MLE). We discover that a two-step spectral method, where
we apply the optimal weighting estimated from the equal weighting vanilla
spectral method, can achieve the same asymptotic efficiency as the MLE. Given
the asymptotic distributions of the estimated preference scores, we also
introduce a comprehensive framework to carry out both one-sample and two-sample
ranking inferences, applicable to both fixed and random graph settings. It is
noteworthy that it is the first time effective two-sample rank testing methods
are proposed. Finally, we substantiate our findings via comprehensive numerical
simulations and subsequently apply our developed methodologies to perform
statistical inferences on statistics journals and movie rankings
System-status-aware Adaptive Network for Online Streaming Video Understanding
Recent years have witnessed great progress in deep neural networks for
real-time applications. However, most existing works do not explicitly consider
the general case where the device's state and the available resources fluctuate
over time, and none of them investigate or address the impact of varying
computational resources for online video understanding tasks. This paper
proposes a System-status-aware Adaptive Network (SAN) that considers the
device's real-time state to provide high-quality predictions with low delay.
Usage of our agent's policy improves efficiency and robustness to fluctuations
of the system status. On two widely used video understanding tasks, SAN obtains
state-of-the-art performance while constantly keeping processing delays low.
Moreover, training such an agent on various types of hardware configurations is
not easy as the labeled training data might not be available, or can be
computationally prohibitive. To address this challenging problem, we propose a
Meta Self-supervised Adaptation (MSA) method that adapts the agent's policy to
new hardware configurations at test-time, allowing for easy deployment of the
model onto other unseen hardware platforms.Comment: Accepted to CVPR 202
Towards Integrated Fine-tuning and Inference when Generative AI meets Edge Intelligence
The high-performance generative artificial intelligence (GAI) represents the
latest evolution of computational intelligence, while the blessing of future 6G
networks also makes edge intelligence (EI) full of development potential. The
inevitable encounter between GAI and EI can unleash new opportunities, where
GAI's pre-training based on massive computing resources and large-scale
unlabeled corpora can provide strong foundational knowledge for EI, while EI
can harness fragmented computing resources to aggregate personalized knowledge
for GAI. However, the natural contradictory features pose significant
challenges to direct knowledge sharing. To address this, in this paper, we
propose the GAI-oriented synthetical network (GaisNet), a collaborative
cloud-edge-end intelligence framework that buffers contradiction leveraging
data-free knowledge relay, where the bidirectional knowledge flow enables GAI's
virtuous-cycle model fine-tuning and task inference, achieving mutualism
between GAI and EI with seamless fusion and collaborative evolution.
Experimental results demonstrate the effectiveness of the proposed mechanisms.
Finally, we discuss the future challenges and directions in the interplay
between GAI and EI.Comment: 11 pages, 8 figures, and 5 table
Learning-Based Client Selection for Federated Learning Services Over Wireless Networks with Constrained Monetary Budgets
We investigate a data quality-aware dynamic client selection problem for
multiple federated learning (FL) services in a wireless network, where each
client offers dynamic datasets for the simultaneous training of multiple FL
services, and each FL service demander has to pay for the clients under
constrained monetary budgets. The problem is formalized as a non-cooperative
Markov game over the training rounds. A multi-agent hybrid deep reinforcement
learning-based algorithm is proposed to optimize the joint client selection and
payment actions, while avoiding action conflicts. Simulation results indicate
that our proposed algorithm can significantly improve training performance.Comment: 6 pages,8 figure
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