README
1Versions of quantreg between 3.70 and 4.75 were removed from the CRAN
2archive due to uncertainties over the licensing status of the fortran
3code in src/cholesky.f. As of 9 March 2012, original authors of cholesky.f,
4Esmond Ng and Barry Peyton, have now, very kindly, given permission to
5use cholesky.f under an open source license. They have requested that
6their code be credited via the following two publications:
7
8 Esmond G. Ng and Barry W. Peyton, "Block sparse Cholesky algorithms
9 on advanced uniprocessor computers". SIAM J. Sci. Stat. Comput.
10 14 (1993), pp. 1034-1056.
11
12 John R. Gilbert, Esmond G. Ng, and Barry W. Peyton, "An efficient
13 algorithm to compute row and column counts for sparse Cholesky
14 factorization". SIAM J. Matrix Anal. Appl. 15 (1994), pp. 1075-1091.
15
16Use of the sparse Cholesky code in cholesky.f in quantreg is limited to calls
17to rqss() or to rq with method = "sfn".
18
19In the event that readers wish to access the intermediate versions of quantreg
20that have been removed from CRAN, they will be available at:
21
22 http://www.econ.uiuc.edu/~roger/research/rq/quantreg
23
24Current versions are best accessed from CRAN and its many mirrors.
25
26