stab: Stability of a chemical product

In EngrExpt: Data sets from "Introductory Statistics for Engineering Experimentation"

Description

Stability of a chemical product

Format

A data frame with 12 observations on the following 4 variables.

temp

a numeric factor at two levels

humidity

a numeric factor at two levels

time

a numeric factor at three levels

y

a numeric vector

Details

The stability of the active ingredient is critical. This study looks at the impact of temperature and humidity on the stability of the active ingredient over time.

References

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

Examples

str(stab)

Example output

Loading required package: lattice
'data.frame':	12 obs. of  4 variables:
 $ temp    : int  23 23 23 23 23 23 35 35 35 35 ...
 $ humidity: int  0 0 0 85 85 85 0 0 0 85 ...
 $ time    : int  1 4 8 1 4 8 1 4 8 1 ...
 $ y       : num  19.4 19.3 19.5 15.9 15.4 15.2 19.2 15.4 14.9 12.3 ...

EngrExpt documentation built on May 1, 2019, 9:15 p.m.