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| GaltonFamilies   | R Documentation   |
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Galton's data on the heights of parents and their children, by family
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Description
~~~~~~~~~~~

This data set lists the individual observations for 934 children in 205
families on which Galton (1886) based his cross-tabulation.

Usage
~~~~~

::

    data(GaltonFamilies)

Format
~~~~~~

A data frame with 934 observations on the following 8 variables.

``family``
    family ID, a factor with levels ``001``-``204``

``father``
    height of father

``mother``
    height of mother

``midparentHeight``
    mid-parent height, calculated as ``(father + 1.08*mother)/2``

``children``
    number of children in this family

``childNum``
    number of this child within family. Children are listed in
    decreasing order of height for boys followed by girls

``gender``
    child gender, a factor with levels ``female`` ``male``

``childHeight``
    height of child

Details
~~~~~~~

Galton's notebook lists 963 children in 205 families ranging from 1-15
adult children children. Of these, 29 had non-numeric heights recorded
and are not included here.

Families are largely listed in decending order of fathers and mothers
height.

Source
~~~~~~

Galton's notebook,
`http://www.medicine.mcgill.ca/epidemiology/hanley/galton/notebook/ <http://www.medicine.mcgill.ca/epidemiology/hanley/galton/notebook/>`_,
transcribed by Beverley Shipley in 2001.

References
~~~~~~~~~~

Galton, F. (1886). Regression Towards Mediocrity in Hereditary Stature
*Journal of the Anthropological Institute*, 15, 246-263

Hanley, J. A. (2004). "Transmuting" Women into Men: Galton's Family Data
on Human Stature. *The American Statistician*, 58, 237-243. See:
`http://www.medicine.mcgill.ca/epidemiology/hanley/galton/ <http://www.medicine.mcgill.ca/epidemiology/hanley/galton/>`_
for source materials.

See Also
~~~~~~~~

``Galton``, ``PearsonLee``

Examples
~~~~~~~~

::

    data(GaltonFamilies)
    str(GaltonFamilies)

    ## reproduce Fig 2 in Hanley (2004)
    library(car)
    scatterplot(childHeight ~ midparentHeight | gender, data=GaltonFamilies, 
        ellipse=TRUE, levels=0.68, legend.coords=list(x=64, y=78))

    # multiply daughters' heights by 1.08
    GF1 <- within(GaltonFamilies, {childHeight <- ifelse (gender=="female", 1.08*childHeight, childHeight)} )
    scatterplot(childHeight ~ midparentHeight | gender, data=GF1, 
        ellipse=TRUE, levels=0.68, legend.coords=list(x=64, y=78))

    # add 5.2 to daughters' heights 
    GF2 <- within(GaltonFamilies, {childHeight <- ifelse (gender=="female", childHeight+5.2, childHeight)} )
    scatterplot(childHeight ~ midparentHeight | gender, data=GF2, 
        ellipse=TRUE, levels=0.68, legend.coords=list(x=64, y=78))

