version      date  description
1.0      01/16/12  The first version on CRAN
1.1	 02/12/12  Plot function for descriptive analysis and bug fixes
1.2	 02/25/12  The option to extract the support parameter is added
1.3      01/24/13  The hierarchical model option is added
1.3.1    02/05/13  Bug fix (hierarchical model without covariates)
1.4.0    04/28/13  Add the varying-lambda hierarchical model