Modified version of the mammal sleep data set that is included in mice.
A dataset with 62 observations of the following 11 variables:
Species of animal
Body weight (kg)
Brain weight (g)
Slow wave ("nondreaming") sleep (hrs/day)
Paradoxical ("dreaming") sleep (hrs/day)
Total sleep (hrs/day) (sum of slow wave and paradoxical sleep)
Maximum life span (years)
Gestation time (days)
Predation index (1-5), 1 = least likely to be preyed upon
Sleep exposure index (1-5), 1 = least exposed (e.g. animal sleeps in a well-protected den), 5 = most exposed
Overall danger index (1-5) based on the above two indices and other information, 1 = least danger (from other animals), 5 = most danger (from other animals)
The original dataset was from a study by Allison and Cicchetti (1976) of 62
mammal species on the interrelationship between sleep, ecological, and
constitutional variables, and was adapted in the mice-package. It
contains missing values on five variables and has been modified such that for
each row, the entries in the column tuples (sws,ps) and
(mls,gt) are either pairwiseNA or pairwise non-NA.