crabSpecies.RdA sample of 200 rock crabs (Leptograpsus variegatus) found in the southern subtropical Pacific Ocean. These are small sea crabs that grow at most to about 50 millimetres of shell width.
The data contain the sex and species of each crab as determined by the researchers (see references).
A data frame with 200 rows and 2 variables
A two level factor distinguishing the species by colour: either "blue" or "orange"
A two level factor identifying the crab's sex: either "male" or "female".
The purpose of this data set is to identify which crabs in lepto belong to each of the four groups identified here.
There are 50 of each combination of factor levels.
Data are a subset of the crabs data set from the MASS package.
Only the species and sex variables appear here and their row order here now match (row for row) the
order of the rows from the physical size measurements on the purple rock crab given in lepto.
This separation now allows clustering methods to be explored on the data set lepto and
compared to the classification by colour (Species) and sex given here.
N.A. Campbell and R.J. Mahon (1974). "A multivariate study of variation in two species of rock crab of the genus Leptograpsus." Australian Journal of Zoology 22, 417-425. <doi:10.1071/ZO9740417>
Venables, W. N. and Ripley, B. D. (2002) Modern Applied Statistics with S. Fourth edition. Springer. <doi:10.1007/978-0-387-21706-2>
R.W. Oldford