Nitrogen concentrations in the Mississippi River

Description

The Mississippi data frame has 37 rows and 3 columns.

Format

This data frame contains the following columns:

influent

an ordered factor with levels 3 < 5 < 2 < 1 < 4 < 6

y

a numeric vector

Type

a factor with levels 1 2 3

Source

Littel, R. C., Milliken, G. A., Stroup, W. W., and Wolfinger, R. D. (1996), SAS System for Mixed Models, SAS Institute (Data Set 4.2).

Examples

library(SASmixed)
options(
  contrasts = c(unordered = "contr.SAS", ordered = "contr.poly"))
data(Mississippi)
formula( Mississippi )
#plot( Mississippi )
fm1Miss <- lme( y ~ 1, data = Mississippi, random = ~ 1 | influent )
summary( fm1Miss )        # compare with output 4.1, p. 142
fm1MLMiss <- update( fm1Miss, method = "ML" )
summary( fm1MLMiss )        # compare with output 4.2, p. 143
random.effects( fm1MLMiss ) # BLUP's of random effects on p. 144
random.effects( fm1MLMiss , aug = TRUE )   # including covariates
random.effects( fm1Miss )   # BLUP's of random effects on p. 142
intervals( fm1Miss )        # interval estimates of variance components
VarCorr( fm1Miss )          # compare to output 4.7, p. 148
fm2Miss <- lme( y ~ Type, data = Mississippi, random = ~ 1 | influent,
      method = "REML" )
summary( fm2Miss )         # compare to output 4.8 and 4.9, pp. 150-152
anova( fm2Miss )