1. Statistics GIDP, Department of Mathematics, University of Arizona, Tucson, AZ 85721, USA
2. Department of System and Industrial Engineering, University of Arizona, Tucson, AZ 85721, USA
3. College of Nursing, University of Arizona, Tucson, AZ 85721, USA
4. Department of Electrical and Computer Engineering, University of Arizona, Tucson, AZ 85721, USA