Chem97 {mlmRev} | R Documentation

## Scores on A-level Chemistry in 1997

### Description

Scores on the 1997 A-level Chemistry examination in Britain. Students are grouped into schools within local education authories. In addition some demographic and pre-test information is provided.

### Usage

    data(Chem97)

### Format

A data frame with 31022 observations on the following 8 variables.

lea
  Local Education Authority - a factor
school
  School identifier - a factor
student
  Student identifier - a factor
score
  Point score on A-level Chemistry in 1997
gender
  Student's gender
age
  Age in month, centred at 222 months or 18.5 years
gcsescore
  Average GCSE score of individual.
gcsecnt
  Average GCSE score of individual, centered at mean.

### Details

This data set is relatively large with 31,022 individuals in 2,280 schools. Note that while this is used, illustratively, to fit Normal response models, the distribution of the response is not well described by a Normal distribution.

### Source

http://multilevel.ioe.ac.uk/softrev/chem97.html

### References

Yang, M., Fielding, A. and Goldstein, H. (2002). Multilevel ordinal models for examination grades (submitted to Statistical Modelling).

### Examples

    str(Chem97)
    summary(Chem97)
    (fm1 <- lmer(score ~ (1|school) + (1|lea), Chem97))
    (fm2 <- lmer(score ~ gcsecnt + (1|school) + (1|lea), Chem97))

[Package mlmRev version 0.995-1 Index]