rsq (version 0.6)

hcrabs: Satellites of Female Horseshoe Crabs

Description

Recorded are the numbers of male satellites, and other characteristics of 173 female horseshoe crabs.

Usage

data("hcrabs")

Format

A data frame with 173 observations on the following 5 variables.

Source

Agresti, A. (2012). An Introduction to Categorical Data Analysis, 3rd edition. Wiley: New Jersey.

Details

A nesting female horseshoe crab may have male crabs residing nearby, called satellites, besides the male crab residing in her nest. Brockmann (1996) investigated factors (including the female crab's color, spine condition, weight, and carapace width) which may influence the presence/obsence of satellite males. This data set has been discussed by Agresti (2002).

References

Brockmann, H. J. (1996). Satellite male groups in horseshoe crabs. Limulus polyphemus. Ethology, 102: 1-21.

Examples

data(hcrabs)
summary(hcrabs)
head(hcrabs)

attach(hcrabs)
y <- ifelse(num.satellites>0,1,0)
bnfit <- glm(y~color+spine+width+weight,family=binomial)
rsq(bnfit)
rsq(bnfit,adj=TRUE)
rsq.partial(bnfit)

quasips <- glm(num.satellites~color+spine+width+weight,family=quasipoisson)
rsq(quasips)
rsq(quasips,adj=TRUE)
rsq.partial(quasips)