alum dataset

Aluminum impurity amounts

As described in Nelson, Coffin and Copeland (2003), Over a 2-hour period, twenty-five 200 gm samples were drawn at randomfrom a process that recycles plastic, and the amount of aluminumimpurities in the sample in ppm was determined for each sample. 1.1

data

Format

A data frame with 25 observations on the following variable.

• ppm: amount of aluminum impurities (ppm)

References

Peter R. Nelson, Marie Coffin and Karen A. F. Copeland (2003), Introductory Statistics for Engineering Experimentation, Elsevier. (Appendix A)

Examples

str(alum)
qqmath(~ ppm, alum, xlab = "Standard normal quantiles",
       aspect = 1, ylab = "Amount of aluminum impurities (ppm)",
       type = c("g","p"))
qqmath(~ log(ppm), alum, xlab = "Standard normal quantiles",
       aspect = 1, type = c("g","p"),
       ylab = "Natural log of amount of aluminum impurities (log(ppm))")