VisualAcuity {vcd}R Documentation

Visual Acuity in Left and Right Eyes

Description

Data from Kendall & Stuart (1961) on unaided vision among 3,242 men and 7,477 women, all aged 30-39 and employed in the U.K. Royal Ordnance factories 1943-1946.

Usage

data("VisualAcuity")

Format

A data frame with 32 observations and 4 variables.

Freq
frequency of visual acuity measurements.
right
visual acuity on right eye.
left
visual acuity on left eye.
gender
factor indicating gender of patient.

Source

M. Friendly (2000), Visualizing Categorical Data: http://euclid.psych.yorku.ca/ftp/sas/vcd/catdata/vision.sas

References

M. G. Kendall & A. Stuart (1961), The Advanced Theory of Statistics, Vol. 2. Griffin, London.

M. Friendly (2000), Visualizing Categorical Data. SAS Institute, Cary, NC.

Examples

data("VisualAcuity")
structable(~ gender + left + right, data = VisualAcuity)

[Package vcd version 1.2-7 Index]