Semiconductor {SASmixed}R Documentation

Semiconductor split-plot experiment

Description

The Semiconductor data frame has 48 rows and 5 columns.

Format

This data frame contains the following columns:

resistance
a numeric vector
ET
a factor with levels 1 to 4 representing etch time.
Wafer
a factor with levels 1 to 3
position
a factor with levels 1 to 4
Grp
an ordered factor with levels 1/1 < 1/2 < 1/3 < 2/1 < 2/2 < 2/3 < 3/1 < 3/2 < 3/3 < 4/1 < 4/2 < 4/3

Details

Source

Littel, R. C., Milliken, G. A., Stroup, W. W., and Wolfinger, R. D. (1996), SAS System for Mixed Models, SAS Institute (Data Set 2.2(b)).

Examples

str(Semiconductor)
if (require("lme4", quietly = TRUE, character = TRUE)) {
  options(contrasts = c(unordered = "contr.SAS", ordered = "contr.poly"))
  print(fm1Semi <- lmer(resistance ~ ET * position + (1|Grp), Semiconductor))
  print(anova(fm1Semi))
  print((fm2Semi <- lmer(resistance ~ ET + position + (1|Grp), Semiconductor)))
  print(anova(fm2Semi))
}

[Package SASmixed version 0.4-2 Index]