chickwts {datasets} | R Documentation

## Chicken Weights by Feed Type

### Description

An experiment was conducted to measure and compare the effectiveness of various feed supplements on the growth rate of chickens.

### Usage

    chickwts

### Format

A data frame with 71 observations on 2 variables.

weight
  a numeric variable giving the chick weight.
feed
  a factor giving the feed type.

### Details

Newly hatched chicks were randomly allocated into six groups, and each group was given a different feed supplement. Their weights in grams after six weeks are given along with feed types.

### Source

Anonymous (1948) Biometrika, 35, 214.

### References

McNeil, D. R. (1977) Interactive Data Analysis. New York: Wiley.

### Examples

    require(stats)
    boxplot(weight ~ feed, data = chickwts, col = "lightgray",
        varwidth = TRUE, notch = TRUE, main = "chickwt data",
        ylab = "Weight at six weeks (gm)")
    anova(fm1 <- lm(weight ~ feed, data = chickwts))
    opar <- par(mfrow = c(2, 2), oma = c(0, 0, 1.1, 0),
                mar = c(4.1, 4.1, 2.1, 1.1))
    plot(fm1)
    par(opar)

[Package datasets version 2.3.1 Index]