APPLICATION OF NON-PARAMETRIC STATISTICS TO EVALUATE THE COMPARABILITY OF ANALYTICAL DATA FROM TWO U. S. GEOLOGICAL SURVEY WATER-QUALITY LABORATORIES.

Dale B. Peart; Linda C. Friedman

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APPLICATION OF NON-PARAMETRIC STATISTICS TO EVALUATE THE COMPARABILITY OF ANALYTICAL DATA FROM TWO U. S. GEOLOGICAL SURVEY WATER-QUALITY LABORATORIES.

Dale B. Peart·Linda C. Friedman

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Abstract

The U. S. Geological Survey operates two water-quality laboratories. The quality of data produced by each laboratory is judged primarily from an evaluation of the data obtained from the analysis of reference samples. Quality-assurance reports that contain an analysis of the results obtained from chemical analysis of these reference materials by the two laboratories are prepared quarterly, and annual summaries of the data are published. The procedures that are used to determine whether a laboratory shows an overall lack of precision or bias involve the application of binomial distributions to the data.

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Dale B. Peart, Linda C. Friedman. 1984. APPLICATION OF NON-PARAMETRIC STATISTICS TO EVALUATE THE COMPARABILITY OF ANALYTICAL DATA FROM TWO U. S. GEOLOGICAL SURVEY WATER-QUALITY LABORATORIES.. https://pubs.usgs.gov/publication/70014065

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