Feature comparison

There are several packages available for analysis of distance sampling data:

• Distance - this package! An easy interface to mrds.
• mrds - the package incorporated into the Windows application Distance (since it supports many features, the syntax can be rather tricky for beginners).
• unmarked - uses the hierarchical modelling approach of Royle et al (2004).
• Rdistance - can be used to perform CDS analyses.

This table provides a feature comparison of the packages:

Feature	Distance	Rdistance	unmarked	mrds
line transects	x	x	x	x
point transects	x		x	x
interval (binned) data	x		x	x
continuous data	x	x		x
half-normal key	x	x	x	x
hazard-rate key	x	x	x	x
uniform key	x	x	x	x
gamma key		x		x
negative exponential key			x
adjustment terms	x	x		x
AIC adjustment selection	x	x
all possible model selection	x
individual level covariates	x			x
transect level covariates	x		x	x
monotonicity constraints	x			x
objects in clusters (group data)	x	x	x	x
left truncation	x	x		x
abundance estimation	x	x	x	x
density estimation	x	x	x	x
user-defined likelihood functions		x
dsm compatability	x			x