Adaptive Estimation of Quadratic Functionals in Nonparametric
Instrumental Variable Models
- URL: http://arxiv.org/abs/2101.12282v1
- Date: Thu, 28 Jan 2021 21:14:02 GMT
- Title: Adaptive Estimation of Quadratic Functionals in Nonparametric
Instrumental Variable Models
- Authors: Christoph Breunig, Xiaohong Chen
- Abstract summary: This paper considers adaptive estimation of quadratic functionals in the nonparametric instrumental variables (NPIV) models.
We first show that a leave-one-out, sieve NPIV estimator attains a convergence rate that coincides with the lower bound.
The adaptive estimator attains the minimax optimal rate in the severely ill-posed case and in the regular, mildly ill-posed case, but up to a multiplicative $sqrtlog n$ in the irregular, mildly ill-posed case.
- Score: 1.6539154611511273
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: This paper considers adaptive estimation of quadratic functionals in the
nonparametric instrumental variables (NPIV) models. Minimax estimation of a
quadratic functional of a NPIV is an important problem in optimal estimation of
a nonlinear functional of an ill-posed inverse regression with an unknown
operator using one random sample. We first show that a leave-one-out, sieve
NPIV estimator of the quadratic functional proposed by \cite{BC2020} attains a
convergence rate that coincides with the lower bound previously derived by
\cite{ChenChristensen2017}. The minimax rate is achieved by the optimal choice
of a key tuning parameter (sieve dimension) that depends on unknown NPIV model
features. We next propose a data driven choice of the tuning parameter based on
Lepski's method. The adaptive estimator attains the minimax optimal rate in the
severely ill-posed case and in the regular, mildly ill-posed case, but up to a
multiplicative $\sqrt{\log n}$ in the irregular, mildly ill-posed case.
Related papers
- Accelerated zero-order SGD under high-order smoothness and overparameterized regime [79.85163929026146]
We present a novel gradient-free algorithm to solve convex optimization problems.
Such problems are encountered in medicine, physics, and machine learning.
We provide convergence guarantees for the proposed algorithm under both types of noise.
arXiv Detail & Related papers (2024-11-21T10:26:17Z) - Multivariate root-n-consistent smoothing parameter free matching estimators and estimators of inverse density weighted expectations [51.000851088730684]
We develop novel modifications of nearest-neighbor and matching estimators which converge at the parametric $sqrt n $-rate.
We stress that our estimators do not involve nonparametric function estimators and in particular do not rely on sample-size dependent parameters smoothing.
arXiv Detail & Related papers (2024-07-11T13:28:34Z) - Should We Learn Most Likely Functions or Parameters? [51.133793272222874]
We investigate the benefits and drawbacks of directly estimating the most likely function implied by the model and the data.
We find that function-space MAP estimation can lead to flatter minima, better generalization, and improved to overfitting.
arXiv Detail & Related papers (2023-11-27T16:39:55Z) - On High dimensional Poisson models with measurement error: hypothesis
testing for nonlinear nonconvex optimization [13.369004892264146]
We estimation and testing regression model with high dimensionals, which has wide applications in analyzing data.
We propose to estimate regression parameter through minimizing penalized consistency.
The proposed method is applied to the Alzheimer's Disease Initiative.
arXiv Detail & Related papers (2022-12-31T06:58:42Z) - Adaptive LASSO estimation for functional hidden dynamic geostatistical
model [69.10717733870575]
We propose a novel model selection algorithm based on a penalized maximum likelihood estimator (PMLE) for functional hiddenstatistical models (f-HD)
The algorithm is based on iterative optimisation and uses an adaptive least absolute shrinkage and selector operator (GMSOLAS) penalty function, wherein the weights are obtained by the unpenalised f-HD maximum-likelihood estimators.
arXiv Detail & Related papers (2022-08-10T19:17:45Z) - Adaptive estimation of a function from its Exponential Radon Transform
in presence of noise [0.0]
We propose a locally adaptive strategy for estimating a function from its Exponential Radon Transform (ERT) data.
We build a non-parametric kernel type estimator and show that for a class of functions comprising a wide Sobolev regularity scale, our proposed strategy follows the minimax optimal rate up to a $logn$ factor.
arXiv Detail & Related papers (2020-11-13T12:54:09Z) - Adaptive, Rate-Optimal Hypothesis Testing in Nonparametric IV Models [2.07706336594149]
We propose a new adaptive hypothesis test for inequality (e.g., monotonicity, convexity) and equality (e.g., parametric, semiparametric) restrictions on a structural function in a nonparametric instrumental variables (NPIV) model.
Our test adapts to the unknown smoothness of alternative functions in the presence of unknown degree of endogeneity and unknown strength of the instruments.
arXiv Detail & Related papers (2020-06-17T01:19:13Z) - SUMO: Unbiased Estimation of Log Marginal Probability for Latent
Variable Models [80.22609163316459]
We introduce an unbiased estimator of the log marginal likelihood and its gradients for latent variable models based on randomized truncation of infinite series.
We show that models trained using our estimator give better test-set likelihoods than a standard importance-sampling based approach for the same average computational cost.
arXiv Detail & Related papers (2020-04-01T11:49:30Z) - 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.