EngrExpt (version 0.1-6)

defoam: Height of solution with defoamer

Description

The height of a solution containing a defoamer in a 50-ml graduated cylinder after being heated to a particular temperature.

References

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

Examples

str(defoam)
dotplot(pH ~ height|conc, defoam, groups = temp, aspect = 0.3,
        xlab = "Height of solution", type = c("p","a"),
        auto.key = list(space = "right", lines = TRUE,
                        title = "Temperature"),
        strip = FALSE, strip.left = TRUE,
        ylab = "pH within concentration")
summary(fm1 <- lm(height ~ (conc + pH + temp)^2, defoam))
summary(fm2 <- lm(height ~ (pH + temp)^3, defoam))