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.
A measured sample of 275 males. Pronotum width (body) and cephalic horn length (horn) were measured in units of mm/100 from digital images using the procedures detailed below. This sample of horn lengths is used to illustrate fitting the mixture of two facing gamma probability distributions.
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