RMstudy:
Collaborative study results for metals in a reference material certification study
Description
A data frame containing reported replicate results, in mg/L, for elements reported
in an inter-laboratory certification study for a candiate drinking reference material.
Format
A data frame with 145 observations on the following 9 variables.
Lab- a factor with levels
Lab1 - Lab29 Arsenic- a numeric vector
Cadmium- a numeric vector
Chromium- a numeric vector
Copper- a numeric vector
Lead- a numeric vector
Manganese- a numeric vector
Nickel- a numeric vector
Zinc- a numeric vector
Source
LGC limited, Teddington, UK (Private communication).Details
The data set includes results for eight of a total of 23 elements studied in an
inter-laboratory study of a candidate reference material. All observations are
reported in mg/l.
Laboratories were asked to report 5 replicate observations for each element. Replicate
observations appear on separate rows. Most but not all laboratories reported five
replicates, and some laboratories reported no results for some elements. The eight
elements included in the data set are those for which no more than three laboratories
failed to report any results. Missing observations are coded NA.Laboratories were coded anonymously in order of receipt of results.