marks {bnlearn} R Documentation

## Examination marks data set

### Description

Examination marks of 88 students on five different topics, from Mardia (1979).

### Usage

``````data(marks)
``````

### Format

The `marks` data set contains the following variables, one for each topic in the examination:

• `MECH` (mechanics)

• `VECT` (vectors)

• `ALG` (algebra)

• `ANL` (analysis)

• `STAT` (statistics)

All are measured on the same scale (0-100).

### Source

Edwards DI (2000). Introduction to Graphical Modelling. Springer, 2nd edition.

Mardia KV, Kent JT, Bibby JM (1979). Multivariate Analysis. Academic Press.

Whittaker J (1990). Graphical Models in Applied Multivariate Statistics. Wiley.

### Examples

``````# This is the undirected graphical model from Edwards (2000).
data(marks)
ug = empty.graph(names(marks))
arcs(ug, check.cycles = FALSE) = matrix(
c("MECH", "VECT", "MECH", "ALG", "VECT", "MECH", "VECT", "ALG",
"ALG",  "MECH", "ALG", "VECT", "ALG",  "ANL", "ALG",  "STAT",
"ANL",  "ALG", "ANL",  "STAT", "STAT", "ALG", "STAT", "ANL"),
ncol = 2, byrow = TRUE,
dimnames = list(c(), c("from", "to")))
## Not run: graphviz.plot(ug)
``````