EngrExpt (version 0.1-6)

sarea: Surface area of silica

Description

Measurements of the surface area ($m^2/g$) of three batches of silica as performed by four different lab technicians.

References

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

Examples

str(sarea)
xtabs(sarea ~ batch + tech, sarea)
dotplot(reorder(tech, sarea) ~ sarea, sarea,
        groups = batch, type = c("p","a"), aspect = "xy",
        ylab = "Technician",
        xlab = expression("Measured surface area " * (m^2/g) *
                          "of silica batches"),
        auto.key = list(columns = 3, lines = TRUE)
)