Accession Number : ADA310117

Title :   Estimating Percentiles from Environmental Samples when all Observations are Nondetectable.

Descriptive Note : Technical rept.

Corporate Author : DESMATICS INC STATE COLLEGE PA

Personal Author(s) : Smith, Dennis E. ; Burns, Kevin C.

PDF Url : ADA310117

Report Date : JUN 1996

Pagination or Media Count : 12

Abstract : Many environmental sampling problems involve some specified regulatory or contractual limit (RL). Often the interest is in estimating the percentile of the underlying contaminant concentration distribution corresponding to RL. In previous reports, we have discussed the problem of determining a lower 100(1-alpha)% confidence limit for that percentile when no observations are observable, but are all known to be less than DL, where DL is less than RL. In this report we extend those results to the situation in which more than a single detection limit is involved.

Descriptors :   *STATISTICAL SAMPLES, *CONFIDENCE LIMITS, CHEMICAL CONTAMINATION, MAXIMUM LIKELIHOOD ESTIMATION, RANDOM VARIABLES, STATISTICAL DATA, REGRESSION ANALYSIS, ENVIRONMENTAL MANAGEMENT, APPLIED MATHEMATICS, CONCENTRATION(CHEMISTRY), NORMAL DISTRIBUTION.

Subject Categories : Statistics and Probability

Distribution Statement : APPROVED FOR PUBLIC RELEASE