Sequential Kernel Embedding for Mediated and Time-Varying Dose Response
Curves
- URL: http://arxiv.org/abs/2111.03950v4
- Date: Wed, 19 Jul 2023 20:46:38 GMT
- Title: Sequential Kernel Embedding for Mediated and Time-Varying Dose Response
Curves
- Authors: Rahul Singh, Liyuan Xu, Arthur Gretton
- Abstract summary: We propose simple nonparametric estimators for mediated and time-varying dose response curves based on kernel ridge regression.
Our key innovation is a reproducing kernel Hilbert space technique called sequential kernel embedding.
- Score: 26.880628841819004
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We propose simple nonparametric estimators for mediated and time-varying dose
response curves based on kernel ridge regression. By embedding Pearl's
mediation formula and Robins' g-formula with kernels, we allow treatments,
mediators, and covariates to be continuous in general spaces, and also allow
for nonlinear treatment-confounder feedback. Our key innovation is a
reproducing kernel Hilbert space technique called sequential kernel embedding,
which we use to construct simple estimators for complex causal estimands. Our
estimators preserve the generality of classic identification while also
achieving nonasymptotic uniform rates. In nonlinear simulations with many
covariates, we demonstrate strong performance. We estimate mediated and
time-varying dose response curves of the US Job Corps, and clean data that may
serve as a benchmark in future work. We extend our results to mediated and
time-varying treatment effects and counterfactual distributions, verifying
semiparametric efficiency and weak convergence.
Related papers
- Generalization in Kernel Regression Under Realistic Assumptions [41.345620270267446]
We provide rigorous bounds for common kernels and for any amount of regularization, noise, any input dimension, and any number of samples.
Our results imply benign overfitting in high input dimensions, nearly tempered overfitting in fixed dimensions, and explicit convergence rates for regularized regression.
As a by-product, we obtain time-dependent bounds for neural networks trained in the kernel regime.
arXiv Detail & Related papers (2023-12-26T10:55:20Z) - Solving Kernel Ridge Regression with Gradient Descent for a Non-Constant Kernel [1.5229257192293204]
KRR is a generalization of linear ridge regression that is non-linear in the data, but linear in the parameters.
We address the effects of changing the kernel during training, something that is investigated in this paper.
We show theoretically and empirically that using a decreasing bandwidth, we are able to achieve both zero training error in combination with good generalization, and a double descent behavior.
arXiv Detail & Related papers (2023-11-03T07:43:53Z) - Stable Nonconvex-Nonconcave Training via Linear Interpolation [51.668052890249726]
This paper presents a theoretical analysis of linearahead as a principled method for stabilizing (large-scale) neural network training.
We argue that instabilities in the optimization process are often caused by the nonmonotonicity of the loss landscape and show how linear can help by leveraging the theory of nonexpansive operators.
arXiv Detail & Related papers (2023-10-20T12:45:12Z) - Nonparametric estimation of a covariate-adjusted counterfactual
treatment regimen response curve [2.7446241148152253]
Flexible estimation of the mean outcome under a treatment regimen is a key step toward personalized medicine.
We propose an inverse probability weighted nonparametrically efficient estimator of the smoothed regimen-response curve function.
Some finite-sample properties are explored with simulations.
arXiv Detail & Related papers (2023-09-28T01:46:24Z) - Curvature-Independent Last-Iterate Convergence for Games on Riemannian
Manifolds [77.4346324549323]
We show that a step size agnostic to the curvature of the manifold achieves a curvature-independent and linear last-iterate convergence rate.
To the best of our knowledge, the possibility of curvature-independent rates and/or last-iterate convergence has not been considered before.
arXiv Detail & Related papers (2023-06-29T01:20:44Z) - Kernel-based off-policy estimation without overlap: Instance optimality
beyond semiparametric efficiency [53.90687548731265]
We study optimal procedures for estimating a linear functional based on observational data.
For any convex and symmetric function class $mathcalF$, we derive a non-asymptotic local minimax bound on the mean-squared error.
arXiv Detail & Related papers (2023-01-16T02:57:37Z) - Instance-Dependent Generalization Bounds via Optimal Transport [51.71650746285469]
Existing generalization bounds fail to explain crucial factors that drive the generalization of modern neural networks.
We derive instance-dependent generalization bounds that depend on the local Lipschitz regularity of the learned prediction function in the data space.
We empirically analyze our generalization bounds for neural networks, showing that the bound values are meaningful and capture the effect of popular regularization methods during training.
arXiv Detail & Related papers (2022-11-02T16:39:42Z) - Adversarial Estimation of Riesz Representers [21.510036777607397]
We propose an adversarial framework to estimate the Riesz representer using general function spaces.
We prove a nonasymptotic mean square rate in terms of an abstract quantity called the critical radius, then specialize it for neural networks, random forests, and reproducing kernel Hilbert spaces as leading cases.
arXiv Detail & Related papers (2020-12-30T19:46:57Z) - Kernel Methods for Causal Functions: Dose, Heterogeneous, and
Incremental Response Curves [26.880628841819004]
We prove uniform consistency with improved finite sample rates via original analysis of generalized kernel ridge regression.
We extend our main results to counterfactual distributions and to causal functions identified by front and back door criteria.
arXiv Detail & Related papers (2020-10-10T00:53:11Z) - Nonparametric Score Estimators [49.42469547970041]
Estimating the score from a set of samples generated by an unknown distribution is a fundamental task in inference and learning of probabilistic models.
We provide a unifying view of these estimators under the framework of regularized nonparametric regression.
We propose score estimators based on iterative regularization that enjoy computational benefits from curl-free kernels and fast convergence.
arXiv Detail & Related papers (2020-05-20T15:01:03Z) - Support recovery and sup-norm convergence rates for sparse pivotal
estimation [79.13844065776928]
In high dimensional sparse regression, pivotal estimators are estimators for which the optimal regularization parameter is independent of the noise level.
We show minimax sup-norm convergence rates for non smoothed and smoothed, single task and multitask square-root Lasso-type estimators.
arXiv Detail & Related papers (2020-01-15T16:11:04Z)
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.