# Quadratic Discriminant Analysis for High-Dimensional Data

@article{Wu2019QuadraticDA, title={Quadratic Discriminant Analysis for High-Dimensional Data}, author={Yilei Wu and Yingli Qin and Mu Zhu}, journal={Statistica Sinica}, year={2019} }

High-dimensional classification is an important and challenging statistical problem. We develop a set of quadratic discriminant rules by simplifying the structure of the covariance matrices instead of imposing sparsity assumptions — either on the covariance matrices themselves (or their inverses), or on the standardized between-class distance. Under moderate conditions on the population covariance matrices, our specialized quadratic discriminant rules enjoy good asymptotic properties…

## 9 Citations

### Sparse quadratic classification rules via linear dimension reduction

- Computer ScienceJ. Multivar. Anal.
- 2019

### A review of quadratic discriminant analysis for high‐dimensional data

- Computer Science
- 2018

The challenges, some existing works, and possibly several future directions with regard to high‐dimensional QDA are to be discussed.

### Quadratic Discriminant Analysis under Moderate Dimension

- Mathematics
- 2018

Quadratic discriminant analysis (QDA) is a simple method to classify a subject into two populations, and was proven to perform as well as the Bayes rule when the data dimension p is fixed. The main…

### Classification in High Dimension Using the Ledoit–Wolf Shrinkage Method

- Computer ScienceMathematics
- 2022

The Stein-type shrinkage estimation of Ledoit and Wolf is employed for high-dimensional data classification and its efficiency is numerically compared to existing methods, including LDA, cross-validation, gLasso, and SVM.

### High‐dimensional covariance matrix estimation using a low‐rank and diagonal decomposition

- Mathematics, Computer ScienceCanadian Journal of Statistics
- 2019

A block‐wise coordinate descent algorithm, which iteratively updates L and D , is then proposed to obtain the estimator in practice and it is shown that the method can be applied to obtain enhanced solutions to the Markowitz portfolio selection problem.

### ST ] 2 9 A ug 2 01 8 Quadratic Discriminant Analysis under Moderate Dimension

- Mathematics
- 2018

Quadratic discriminant analysis (QDA) is a simple method to classify a subject into two populations, and was proven to perform as well as the Bayes rule when the data dimension p is fixed. The main…

### An Auto-Contouring Method for Kidney based on SVM

- Computer Science
- 2021

The experiment showed that, the automatic contour method based on support vector machine has better classification performance than most classification algorithms.

### Phase Transitions for High-Dimensional Quadratic Discriminant Analysis with Rare and Weak Signals

- Mathematics, Computer Science
- 2021

The results suggest that the quadratic term has major influence over the LDA for the classification decision and classification accuracy, especially when μk and Ωk are both known and when all the classifiers will fail.

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