Accession Number : ADA265557


Title :   Markov Chains for Random Urinalysis II: Age-Test Model with Absorbing State


Descriptive Note : Final rept. Oct-Feb 1992


Corporate Author : NAVY PERSONNEL RESEARCH AND DEVELOPMENTCENTER SAN DIEGO CA


Personal Author(s) : Boyle, James P ; Hentschel, Douglas J ; Thompson, Theodore J


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a265557.pdf


Report Date : May 1993


Pagination or Media Count : 26


Abstract : This is the second of a series of papers on the use of Markov chains to model random urinalysis programs. Previous work introduced the age-test Markov chain. This chain was used to model random urinalysis strategies stratified by time since last tested. This paper extends the age-test model by including an absorbing state for detection of drug users. We quantify the extent to which age-test urinalysis strategies can be gamed by drug users. The theory and formula for calculating the distribution of time to absorption (e.g., detection of drug users), the mean time to absorption and the expected number of visits to intermediate states (e.g., number of tests) prior to detection are developed. This model is used to analyze three age-test strategies.... Drug urinalysis, Markov chains, Stratified random sampling, Age-test model.


Descriptors :   *DRUG USERS , *URINALYSIS , STRATEGY , BIOCHEMISTRY , THEORY , PROBABILITY , SAMPLING , PHYSIOLOGY , ABSORPTION , BIOLOGICAL DETECTION , DRUGS , GAME THEORY


Subject Categories : Anatomy and Physiology
      Medicine and Medical Research


Distribution Statement : APPROVED FOR PUBLIC RELEASE