Award Date

1-1-2002

Degree Type

Thesis

Degree Name

Master of Science (MS)

Department

Mathematics

First Committee Member

Ashok Singh

Number of Pages

151

Abstract

Remediation decisions at contaminated sites are determined by comparing the Upper Confidence Limit (UCL) of the mean contaminant to a site-specific action level. The Environmental Protection Agency (EPA) has established methods for computing this UCL, also called the Exposure Point Concentration (EPC) term; The UCL formula depends upon the distribution of the contaminant concentrations, which are often positively skewed. The EPA frequently recommends the Lognormal distribution to model such data. However, that assumption often causes the UCL to be unreliable. What is the role of skewness in computing UCL statistics over different distributions? Computer simulation is used to test a range of skewness values over three similarly shaped distributions: Lognormal, Gamma, and Weibull. Three statistical tests will also be evaluated: Student's t-Statistic, Chebychev's Inequality, and Land's H-Statistic to compute the UCL. By modeling skewness effectively, we can determine the most appropriate distribution and statistical method to use in computing UCLs.

Keywords

Comparison; Confidence; Distribution; Limits; Skewed; Upper

Controlled Subject

Mathematics

File Format

pdf

File Size

3717.12 KB

Degree Grantor

University of Nevada, Las Vegas

Language

English

Permissions

If you are the rightful copyright holder of this dissertation or thesis and wish to have the full text removed from Digital Scholarship@UNLV, please submit a request to digitalscholarship@unlv.edu and include clear identification of the work, preferably with URL.

Identifier

https://doi.org/10.25669/qsxx-dv5e


Share

COinS