skulls {HSAUR} | R Documentation

## Egyptian Skulls

### Description

Measurements made on Egyptian skulls from five epochs.

### Usage

    data("skulls")

### Format

A data frame with 150 observations on the following 5 variables.

`epoch`
  the epoch the skull as assigned to, a factor with levels `c4000BC` `c3300BC`, `c1850BC`, `c200BC`, and `cAD150`, where the years are only given approximately, of course.
`mb`
  maximum breaths of the skull.
`bh`
  basibregmatic heights of the skull.
`bl`
  basialiveolar length of the skull.
`nh`
  nasal heights of the skull.

### Details

The question is whether the measurements change over time. Non-constant measurements of the skulls over time would indicate interbreeding with immigrant populations.

### Source

D. J. Hand, F. Daly, A. D. Lunn, K. J. McConway and E. Ostrowski (1994). A Handbook of Small Datasets, Chapman and Hall/CRC, London.

### Examples

      data("skulls", package = "HSAUR")
      means <- tapply(1:nrow(skulls), skulls$epoch, function(i)
                   apply(skulls[i,colnames(skulls)[-1]], 2, mean))
      means <- matrix(unlist(means), nrow = length(means), byrow = TRUE)
      colnames(means) <- colnames(skulls)[-1]
      rownames(means) <- levels(skulls$epoch)
      pairs(means,
          panel = function(x, y) {
              text(x, y, levels(skulls$epoch))
          })

[Package HSAUR version 1.2-3 Index]