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Sparsity Inducing Prior Distributions for Correlation Matrices of Longitudinal Data
| Content Provider | Scilit |
|---|---|
| Author | Gaskins, J. T. Daniels, M. J. Marcus, B. H. |
| Copyright Year | 2014 |
| Description | For longitudinal data, the modeling of a correlation matrix R can be a difficult statistical task due to both the positive definite and the unit diagonal constraints. Because the number of parameters increases quadratically in the dimension, it is often useful to consider a sparse parameterization. We introduce a pair of prior distributions on the set of correlation matrices for longitudinal data through the partial autocorrelations (PACs), which vary independently over (−1,1). The first prior shrinks each of the PACs toward zero with increasingly aggressive shrinkage in lag. The second prior (a selection prior) is a mixture of a zero point mass and a continuous component for each PAC, allowing for a sparse representation. The structure implied under our priors is readily interpretable for time-ordered responses because each zero PAC implies a conditional independence relationship in the distribution of the data. Selection priors on the PACs provide a computationally attractive alternative to selection on the elements of R or $R^{− 1}$ for ordered data. These priors allow for data-dependent shrinkage/selection under an intuitive parameterization in an unconstrained setting. The proposed priors are compared to standard methods through a simulation study and illustrated using a multivariate probit data example. Supplemental materials for this article (appendix, data, and R code) are available online. |
| Related Links | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4217169/pdf |
| Ending Page | 984 |
| Page Count | 19 |
| Starting Page | 966 |
| ISSN | 10618600 |
| e-ISSN | 15372715 |
| DOI | 10.1080/10618600.2013.852553 |
| Journal | Journal of Computational and Graphical Statistics |
| Issue Number | 4 |
| Volume Number | 23 |
| Language | English |
| Publisher | Informa UK Limited |
| Publisher Date | 2014-10-02 |
| Access Restriction | Open |
| Subject Keyword | Journal: Journal of Computational and Graphical Statistics Statistics and Probability Bayesian Methods Correlation Matrix Longitudinal Data Multivariate Probit Partial Autocorrelation Selection Priors Shrinkage |
| Content Type | Text |
| Resource Type | Article |
| Subject | Statistics and Probability Discrete Mathematics and Combinatorics Statistics, Probability and Uncertainty |