Mercury level in employee urine samples
Mercury level in employee urine samples
A data frame with 12 observations on the following 5 variables.
monthan ordered factor with levels from
January to December
person1mercury concentration in person 1's urine
person2mercury concentration in person 2's urine
person3mercury concentration in person 3's urine
person4mercury concentration in person 4's urine
Employees who work in a high risk area of a chemical plant are monitored monthly for mercury exposure.
Peter R. Nelson, Marie Coffin and Karen A. F. Copeland (2003), Introductory Statistics for Engineering Experimentation, Elsevier. (Appendix A)
str(urine)
dotplot(month ~ person1 + person2 + person3 + person4, urine,
outer = FALSE, type = c("p","l"),
auto.key = list(columns = 2, lines = TRUE, points = FALSE),
xlab = "Mercury level in urine")Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.