# gasurv3

Calculates max likelihood estimates using a genetic algorithm

## Contents

## Syntax

[q, info, endPop, bPop, traceInfo] = **gasurv3**(func, p, t, x, y, Z)

## Description

Calculates max likelihood estimates using a genetic algorithm for trivariate data

Input

- func: string with name of user-defined function

f = func (p, t, x, y) with p: np-vector; t: nt-vector; x: nx-vector; y: ny-vector f: (nt,nx*ny)-matrix with model-predictions for surviving numbers

- p: (np,2) matrix with

p(:,1) initial guesses for parameter values p(:,2) binaries with yes or no iteration (optional)

- t: (nt,1)-vector with first independent variable (time)
- x: (nx,1)-vector with second independent variable
- y: (ny,1)-vector with third independent variable
- Z: (nt,nx*ny)-matrix with surviving numbers

Output

- q: matrix like p, but with ml-estimates
- info: 1 if convergence has been successful; 0 otherwise
- endPop: the final population; individual in each row; last column is minus weighted sum of squares
- bPop: a trace of the best population
- traceInfo: a matrix of best and means of the ga for each generation

## Remarks

Set options with **garegr_options**. Similar to **scsurv3**, but slower and a larger bassin of attraction.

Modified from gaot package version 1996/02/02: C.R. Houck, J.Joines, and M.Kay. A genetic algorithm for function optimization: A Matlab implementation. ACM Transactions on Mathmatical Software, Submitted 1996; binary and order options removed gasurv calls for: User-defined function: 'func'

Crossover Operators: simplexover heuristicxover arithxover Mutation Operators: boundarymutation multinonunifmutation nonunifmutation unifmutation Selection Functions: normgeomselect roulette tournselect Utility functions: cat Option setting: garegr_options