x_gideon: Horn measurements of the rhinoceros beetle _Xylotrupes_...

In discrimARTs: Discrimination of Alternative Reproductive Tactics (ARTs).

Description

A measured sample of 177 males. Pronotum width (body) and pronotal horn length (horn) were measured in mm/10 with a slide micrometer.
This sample of horn lengths is used to illustrate fitting the mixture of two normal probability distributions.

Usage

data(x_gideon)

Format

A data frame with 177 observations on the following 2 variables.

body

Pronotum width (mm/10)

horn

Pronotal horn length (mm/10)

Details

Xylotrupes gideon:
Collection data for the measured sample of the dynastine rhinoceros beetle Xylotrupes gideon:
Lampung Province, Sumatra, Indonesia; 1999;
collected by Agusyanto Hasan.

A measured sample of 177 males was selected from the above total sample of 193. Pronotum width was measured at its greatest width.
Pronotal horn length was measured from the mid-dorsal point of the posterior margin of the pronotum to the anterior apex of the left line of the pronotal horn.

Source

Rowland, J.M. 2003. Male horn dimorphism, phylogeny and systematics of rhinoceros beetles of the genus
Xylotrupes (Scarabaeidae: Coleoptera). Aust. J. Zool., 51: 213-258.

References

Rowland JM, Qualls CR. 2005. Likelihood models for discriminating alternative phenotypes in morphologically dimorphic species.
Evolutionary Ecology Research 7: 421-434.

See Also

mix.mle, o_taurus

Examples

data(x_gideon)
## Scatter plot of horn versus body showing trait scaling
plot(x_gideon$horn, x_gideon$body)

## Plot histogram with overlaid density plot
hist(x_gideon$horn, freq=FALSE)
points( x_gideon$horn, rep(0, nrow(x_gideon)))

## Estimation of mixture of normals
fit.gideon <- mix.mle(x_gideon$horn, method='normal', 
    mix.prob=0.5, dist1.par1=100, dist1.par2=10, dist2.par1=300, dist2.par2=10)

print(fit.gideon)
plot(fit.gideon)

Example output

Loading required package: grid
Loading required package: RUnit
$method
[1] "normal"

$convergence
[1] 0

$neglogLik
[1] 2027.126

$pars.init
  mix.prob dist1.par1 dist1.par2 dist2.par1 dist2.par2 
       0.5      100.0       10.0      300.0       10.0 

$MLE.est
   mix.prob  dist1.par1  dist1.par2  dist2.par1  dist2.par2 
  0.5548266 154.8120619  31.4701818 312.5941528  47.9843940 

NULL

discrimARTs documentation built on May 2, 2019, 2:04 a.m.