ID: Index of dissimilarity

In timriffe/DemoTools: Standardize, Evaluate, and Adjust Demographic Data

Index of dissimilarity

Description

Calculate the index of dissimilarity between two population structures. A returned value of zero means that the two population have identical structure. A value of 100 means that the populations have no overlap at all (not likely for populations structured only by age). This is a simple measure of distribution overlap on the absolute scale.

Usage

ID(pop1, pop2)

Arguments

pop1	numeric. Vector of counts from population 1.
pop2	numeric. Vector of counts from population 2.

Details

Input populations are assumed to be ordered in the same way prior to calling the function. It is only checked that the vectors are of the same length. The input arguments could indeed be populations structured on multiple variables (more than just age), as long as they are ordered in the same way.

Value

The value of the index ranging from 0 to infinity..

References

\insertRef

siegel2004methodsDemoTools

Examples

pop1                     <- c(7.38,14.16,14.79,17.36,15.11,10.14,8.50,7.28,5.28)
pop2                     <- c(6.48,12.27,15.25,15.10,14.66,10.80,8.95,9.28,7.21)
ID(pop1, pop2)     # 5.5 reproduces table 7.20 of Siegel & Swanson (2004)
ID(pop1, pop1)     # identical = 0
ID(pop1, pop2 * 2) # scale invariant
pop3                     <- pop4         <- pop1
pop3[1:5]                <- 0
pop4[6:length(pop4)]     <- 0
ID(pop3, pop4)     # no overlap = 100.

timriffe/DemoTools documentation built on Oct. 14, 2024, 12:53 p.m.