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Upper Midwest Environmental Sciences Center

The Upper Mississippi River Restoration Program

Long Term Resource Monitoring

LTRM Sampling Design and Statistics

Upper Mississippi River Restoration - Environmental Management Program U. S. Army Corps of Enineers

Aquatic Vegetation
Water Quality


The Long Term Resource Monitoring (LTRM) sampling design and statistics web pages describe LTRM sampling designs and present design-based methods for estimating status and trends from LTRM monitoring data. Design-based estimation methods rely on properties of the sampling design, and therefore are typically viewed as less subjective than estimates from statistical models. The following link leads to web pages that provide technical guidance for estimating means and temporal trends using LTRM data:

The following links provide background information on LTRM sampling designs and analyses that may be helpful when estimating means and temporal trends:

The following links cover statistical topics not strictly associated with design-based estimation:


Contact: Questions or comments may be directed to Brian Gray, LTRM statistician, Upper Midwest Environmental Sciences Center, La Crosse, Wisconsin, at

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Page Last Modified: June 21, 2016