## The Annals of Statistics

### Approximating conditional distribution functions using dimension reduction

#### Abstract

Motivated by applications to prediction and forecasting, we suggest methods for approximating the conditional distribution function of a random variable Y given a dependent random d-vector X. The idea is to estimate not the distribution of Y|X, but that of YTX, where the unit vector θ is selected so that the approximation is optimal under a least-squares criterion. We show that θ may be estimated root-n consistently. Furthermore, estimation of the conditional distribution function of Y, given θTX, has the same first-order asymptotic properties that it would enjoy if θ were known. The proposed method is illustrated using both simulated and real-data examples, showing its effectiveness for both independent datasets and data from time series. Numerical work corroborates the theoretical result that θ can be estimated particularly accurately.

#### Article information

Source
Ann. Statist., Volume 33, Number 3 (2005), 1404-1421.

Dates
First available in Project Euclid: 1 July 2005

https://projecteuclid.org/euclid.aos/1120224107

Digital Object Identifier
doi:10.1214/009053604000001282

Mathematical Reviews number (MathSciNet)
MR2195640

Zentralblatt MATH identifier
1072.62008

Subjects
Primary: 62E17: Approximations to distributions (nonasymptotic)
Secondary: 62G05: Estimation 62G20: Asymptotic properties

#### Citation

Hall, Peter; Yao, Qiwei. Approximating conditional distribution functions using dimension reduction. Ann. Statist. 33 (2005), no. 3, 1404--1421. doi:10.1214/009053604000001282. https://projecteuclid.org/euclid.aos/1120224107

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