Likelihood-Free Inference with Generative Neural Networks via Scoring
Rule Minimization
- URL: http://arxiv.org/abs/2205.15784v1
- Date: Tue, 31 May 2022 13:32:55 GMT
- Title: Likelihood-Free Inference with Generative Neural Networks via Scoring
Rule Minimization
- Authors: Lorenzo Pacchiardi and Ritabrata Dutta
- Abstract summary: Inference methods yield posterior approximations for simulator models with intractable likelihood.
Many works trained neural networks to approximate either the intractable likelihood or the posterior directly.
Here, we propose to approximate the posterior with generative networks trained by Scoring Rule minimization.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Bayesian Likelihood-Free Inference methods yield posterior approximations for
simulator models with intractable likelihood. Recently, many works trained
neural networks to approximate either the intractable likelihood or the
posterior directly. Most proposals use normalizing flows, namely neural
networks parametrizing invertible maps used to transform samples from an
underlying base measure; the probability density of the transformed samples is
then accessible and the normalizing flow can be trained via maximum likelihood
on simulated parameter-observation pairs. A recent work [Ramesh et al., 2022]
approximated instead the posterior with generative networks, which drop the
invertibility requirement and are thus a more flexible class of distributions
scaling to high-dimensional and structured data. However, generative networks
only allow sampling from the parametrized distribution; for this reason, Ramesh
et al. [2022] follows the common solution of adversarial training, where the
generative network plays a min-max game against a "critic" network. This
procedure is unstable and can lead to a learned distribution underestimating
the uncertainty - in extreme cases collapsing to a single point. Here, we
propose to approximate the posterior with generative networks trained by
Scoring Rule minimization, an overlooked adversarial-free method enabling
smooth training and better uncertainty quantification. In simulation studies,
the Scoring Rule approach yields better performances with shorter training time
with respect to the adversarial framework.
Related papers
- Scalable Bayesian Inference in the Era of Deep Learning: From Gaussian Processes to Deep Neural Networks [0.5827521884806072]
Large neural networks trained on large datasets have become the dominant paradigm in machine learning.
This thesis develops scalable methods to equip neural networks with model uncertainty.
arXiv Detail & Related papers (2024-04-29T23:38:58Z) - Sampling weights of deep neural networks [1.2370077627846041]
We introduce a probability distribution, combined with an efficient sampling algorithm, for weights and biases of fully-connected neural networks.
In a supervised learning context, no iterative optimization or gradient computations of internal network parameters are needed.
We prove that sampled networks are universal approximators.
arXiv Detail & Related papers (2023-06-29T10:13:36Z) - Improved uncertainty quantification for neural networks with Bayesian
last layer [0.0]
Uncertainty quantification is an important task in machine learning.
We present a reformulation of the log-marginal likelihood of a NN with BLL which allows for efficient training using backpropagation.
arXiv Detail & Related papers (2023-02-21T20:23:56Z) - An unfolding method based on conditional Invertible Neural Networks
(cINN) using iterative training [0.0]
Generative networks like invertible neural networks(INN) enable a probabilistic unfolding.
We introduce the iterative conditional INN(IcINN) for unfolding that adjusts for deviations between simulated training samples and data.
arXiv Detail & Related papers (2022-12-16T19:00:05Z) - GFlowOut: Dropout with Generative Flow Networks [76.59535235717631]
Monte Carlo Dropout has been widely used as a relatively cheap way for approximate Inference.
Recent works show that the dropout mask can be viewed as a latent variable, which can be inferred with variational inference.
GFlowOutleverages the recently proposed probabilistic framework of Generative Flow Networks (GFlowNets) to learn the posterior distribution over dropout masks.
arXiv Detail & Related papers (2022-10-24T03:00:01Z) - Implicit Bias in Leaky ReLU Networks Trained on High-Dimensional Data [63.34506218832164]
In this work, we investigate the implicit bias of gradient flow and gradient descent in two-layer fully-connected neural networks with ReLU activations.
For gradient flow, we leverage recent work on the implicit bias for homogeneous neural networks to show that leakyally, gradient flow produces a neural network with rank at most two.
For gradient descent, provided the random variance is small enough, we show that a single step of gradient descent suffices to drastically reduce the rank of the network, and that the rank remains small throughout training.
arXiv Detail & Related papers (2022-10-13T15:09:54Z) - Layer Ensembles [95.42181254494287]
We introduce a method for uncertainty estimation that considers a set of independent categorical distributions for each layer of the network.
We show that the method can be further improved by ranking samples, resulting in models that require less memory and time to run.
arXiv Detail & Related papers (2022-10-10T17:52:47Z) - Bayesian Nested Neural Networks for Uncertainty Calibration and Adaptive
Compression [40.35734017517066]
Nested networks or slimmable networks are neural networks whose architectures can be adjusted instantly during testing time.
Recent studies have focused on a "nested dropout" layer, which is able to order the nodes of a layer by importance during training.
arXiv Detail & Related papers (2021-01-27T12:34:58Z) - A Bayesian Perspective on Training Speed and Model Selection [51.15664724311443]
We show that a measure of a model's training speed can be used to estimate its marginal likelihood.
We verify our results in model selection tasks for linear models and for the infinite-width limit of deep neural networks.
Our results suggest a promising new direction towards explaining why neural networks trained with gradient descent are biased towards functions that generalize well.
arXiv Detail & Related papers (2020-10-27T17:56:14Z) - Compressive sensing with un-trained neural networks: Gradient descent
finds the smoothest approximation [60.80172153614544]
Un-trained convolutional neural networks have emerged as highly successful tools for image recovery and restoration.
We show that an un-trained convolutional neural network can approximately reconstruct signals and images that are sufficiently structured, from a near minimal number of random measurements.
arXiv Detail & Related papers (2020-05-07T15:57:25Z) - MSE-Optimal Neural Network Initialization via Layer Fusion [68.72356718879428]
Deep neural networks achieve state-of-the-art performance for a range of classification and inference tasks.
The use of gradient combined nonvolutionity renders learning susceptible to novel problems.
We propose fusing neighboring layers of deeper networks that are trained with random variables.
arXiv Detail & Related papers (2020-01-28T18:25:15Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.