Department of Environmental & Aquatic Animal Health - Research Programs & Projects

Environmental Toxicology and Risk Assessment

Chesapeake Short Course Series. Summer 2002.

Short course: Practical Statistics for Environmental Measurement

Course Objective

To present practical methods for the analysis of environmental data and to apply them with PC-based software. Emphasis is placed on the practicality and soundness of techniques.

Course Structure

Morning lectures outline methods and practical aspects of their implementation. Example data sets will be analyzed using commonly available PC-based software during the afternoon sessions.

Course Outline

Regions of Quantitation

• Relative Measurement Uncertainty
• Limits of Detection, Quantitation, Linearity and Reporting.
• Types of Detection Limits

What to do with Nondetects?

• Definitions
• Reporting of Detection Limit
• Estimation of Mean and Standard Deviation for Censored Data
• Winsorization
• Distributional Methods
• Robust Methods
• Methods Applied if Several Detection Limits are Present in the Data Set

• Hypothesis Testing with Censored Data

What Types of Blank should I use?

• Overview
• Estimating Effects of the Blank on the Measurement Process
• Control Charts for Blanks
• Types of Blanks and their Use

Bias (Accuracy) and Precision

• Estimation of Accuracy
• Use and Sources of Reference Materials
• Estimation of Precision
• Control Charts for Accuracy and Precision
• Shewhart Charts
• Cusum Charts

Variance Structure

• Variance Structure in an Analytical Scheme
• Measurement Noise Bottlenecks
• Variance Structure in Field Sampling
• Optimizing Sampling

How Many of What Size Sample to Take?

• Reasonable Estimates
• Optimal Number of Individuals to Sample
• Optimal Weight or Volume to Sample
• Well-Mixed Materials
• Poorly-Mixed Materials
• Resampling Techniques

What to do with Outliers?

• General Rules about Outliers
• Single Suspect Observation
• Several Suspect Observations

Regression and Standard Curves

• General Regression
• Prediction by Inverse Prediction
• Nonparametric Regression
• How Good is Your Calibration Curve?

Instructors

Dr. Mike Newman spent 20 years as an environmental scientist, during which time he developed extensive expertise in the field of environmental measurement and modeling. He authored and edited several books, and is currently an editor for Environmental Toxicology & Chemistry. 

David Ownby worked for a nationally recognized environmental consulting firm as an environmental risk assessor before coming to VIMS to pursue a Ph.D. 

Application form and address

Optional Textbook

Descriptions of techniques and examples are taken from the book, Quantitative Methods in Aquatic Ecotoxicology by M.C. Newman. 1995. Lewis Publishers, Chelsea, MI., pp. 408. Although not required for this course, the textbook can be purchased during registration.

Further Information & Application To:

Dr. Michael C. Newman (Instructor)
Mr. David R. Ownby (Instructor)
The College of William and Mary
Department of Environmental Sciences
Virginia Institute of Marine Sciences
Gloucester Point, VA 23062-1346
Telephone: (804) 684-7105 or 7256
Fax: (804) 684-7186
e-mail: newman@vims.edu or downby@vims.edu