darwin {marg}R Documentation

Darwin's Data on Growth Rates of Plants

Description

The darwin data frame has 15 rows and 3 columns.

Charles Darwin conducted an experiment to examine the superiority of cross-fertilized plants over self-fertilized plants. 15 pairs of plants were used. Each pair consisted of one cross-fertilized plant and one self-fertilized plant which germinated at the same time and grew in the same pot. The heights of the plants were measured at a fixed time after planting. Four different pots were used.

Usage

data(darwin)

Format

This data frame contains the following columns:

cross

the heights of the cross-fertilized plants (in inches);

self

the heights of the self-fertilized plants (in inches);

pot

a factor variable for the pot number.

Source

The data were obtained from

Andrews, D. F. and Herzberg, A. M. (1985) Data: A Collection of Problems From Many Fields for the Student and Research Worker (Chapter 2). New York: Springer-Verlag.

References

Darwin, C. (1878) The Effects of Cross and Self Fertilisation in the Vegetable Kingdom (2nd ed.). London: John Murray.

Examples

data(darwin)
plot(cross - self ~ pot, data = darwin)

[Package marg version 1.2-2.1 Index]