R: Visual Acuity in Left and Right Eyes

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)
    sieve(Freq ~ left + right | gender, data = VisualAcuity, shade = TRUE)
    cotabplot(Freq ~ left + right | gender, data = VisualAcuity,
              panel = cotab_agreementplot)

[Package vcd version 1.4-4 Index]