A package to compute and tune some positive definite and sparse covariance estimators
The main functions are pdsoft, pdsoft.cv,
band.chol, and band.chol.cv.
Rothman, A. J., Levina, E., and Zhu, J. (2010). A new approach to Cholesky-based covariance regularization in high dimensions. Biometrika 97(3): 539-550.
Rothman, A. J. (2012). Positive definite estimators of large covariance matrices. Biometrika 99(3): 733-740