Mark and Recapture

Mark and recapture is a method commonly used in ecology to estimate an animal population's size. It's also can be used on development/testing teams to estimate bug population. Having two teams do individual bug audits, and throwing their values into the algorithm to recieve an estimate.

Install

npm i mark-and-recapture

Usage example

var MaR = require('mark-and-recapture');
//function is curried so you can pass it it's needed values like so...
MaR.estimate(10)(20)(6);

Should return and object...

{
  lincolnIndex: 33,
  chapmanIndex: 32,
  basyesianEstimate: 42,
  basyesianEstimateStandardDeviation: 16.345871038277526
}

What are the values am I passing in?

In the function, MaR.estimate(capInital)(capCurrent)(capIntersection) the first value capInital is the first capture (software bugs/animals/whatever...), the second value capCurrent is the second round of capturing, and finally capIntersection is the "overlap" or intersection of both rounds of capturing. Id est, what of bugs/animals/whatever in both of the previous rounds of capturing are the same.

A scenario

Team A, goes out into the forest to search for Humming birds, they capture, and tag 10 Humming Birds. Later, Team B goes out and does the same and captures 20 Humming Birds, of the 20 that they caught, 6 of them were already tagged by Team A! From this information, we can glean that, using the proper mathmatical algorithms, we can make a pretty accruate estimate of the population.