| 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)