GA4Stratification (version 1.0)

GA4StratificationP4m: The mutation operation in genetic algorithm for the determination of stratum boundaries and sample sizes of each stratum in stratified sampling

Description

This is the mutation operation in the Genetic Algorithm approach for the determination of the stratum boundaries and sample sizes in each stratum in stratified sampling with an GA Sample Allocation Scheme.

Usage

GA4StratificationP4m(mutationGeneration, numberOfStrata, mutationRate, it)

Arguments

mutationGeneration

The generation that will be crossovered and transfered to the next generation.

numberOfStrata

An integer: The number of strata.

mutationRate

A numeric: The mutation rate in the Genetic Algorithm process. Mutation rate must be in between 0 and 1, inclusive. Small levels of mutation rate is preferable in Genetic Algorithm approach.

it

An integer: The number of the iteration

References

http://ideas.repec.org/a/eee/csdana/v52y2007i1p53-67.html

http://www.sciencedirect.com/science/article/B6V8V-4NHM520-1/2/a21e0295aa1616ff56da1ddf2c0ba1ac

See Also

GA4StratificationP4 GA4StratificationP4fit GA4StratificationP4fitt GA4StratificationP4x

GA4StratificationSelection randomnumGenerator

Examples

## The function is currently defined as
function(mutationGeneration,numberOfStrata,mutationRate,it)
   {

   	rowOfMutationGeneration=nrow(mutationGeneration)
   	colOfMutationGeneration=ncol(mutationGeneration)
	c=colOfMutationGeneration-numberOfStrata
   	for ( i in 1:rowOfMutationGeneration)
   	{
    	   if ( runif(1,0,1) < mutationRate )
 	   {
		for ( k in 1:2 )
  		{
	         if ( runif(1,0,1) < 0.35 )
		   {
			if ( it<100 )
			{
	               ones=which(mutationGeneration[i,1:c]==1,arr.ind=TRUE)
      	         zeros=which(mutationGeneration[i,1:c]==0,arr.ind=TRUE)
            	   mutationPoint=ones[sample(1:(length(ones)-1),1)]
	               mutationPoint1=zeros[sample(1:length(zeros),1)]
	               mutationGeneration[i,mutationPoint]=0
	               mutationGeneration[i,mutationPoint1]=1
            	} else
			{ 
	               ones=which(mutationGeneration[i,1:c]==1,arr.ind=TRUE)
            	   mutationPoint=ones[sample(1:(length(ones)-1),1)]
                     if ( runif(1,0,1)<0.51 )
		         {
				if ( mutationGeneration[i,(mutationPoint+1)]==0 )
				{
					mutationGeneration[i,mutationPoint]=0
		    			mutationGeneration[i,(mutationPoint+1)]=1
              		}
			   } else if ( mutationPoint>1)
			   {
				if ( mutationGeneration[i,(mutationPoint-1)]==0 ) 
				{
				      mutationGeneration[i,mutationPoint]=0
				      mutationGeneration[i,mutationPoint-1]=1    
				}
			   }
			}
    		} else
		{
		   mutationPoint=sample((c+1):(c+numberOfStrata),1)
		   mutationPoint1=sample((c+1):(c+numberOfStrata),1)

	         while  ( mutationPoint == mutationPoint1 )
		   {
			mutationPoint=sample((c+1):(c+numberOfStrata),1)
		   	mutationPoint1=sample((c+1):(c+numberOfStrata),1)
		   }
     
               if (mutationGeneration[i,mutationPoint]>2 & mutationGeneration[i,mutationPoint1]>2)
		   {
			if (runif(1,0,1)< 0.51)
			{
				mutationGeneration[i,mutationPoint]=mutationGeneration[i,mutationPoint]-1
		      	mutationGeneration[i,mutationPoint1]=mutationGeneration[i,mutationPoint1]+1

           		} else
			{
		            mutationGeneration[i,mutationPoint]=mutationGeneration[i,mutationPoint]+1
		            mutationGeneration[i,mutationPoint1]=mutationGeneration[i,mutationPoint1]-1           
			}

 		   } else if (mutationGeneration[i,mutationPoint]==2 & mutationGeneration[i,mutationPoint1]>2)
		   {
			mutationGeneration[i,mutationPoint]=mutationGeneration[i,mutationPoint]+1
           		mutationGeneration[i,mutationPoint1]=mutationGeneration[i,mutationPoint1]-1

          	   } else (mutationGeneration[i,mutationPoint]>2 & mutationGeneration[i,mutationPoint1]==2)

	            mutationGeneration[i,mutationPoint]=mutationGeneration[i,mutationPoint]-1
       	      mutationGeneration[i,mutationPoint1]=mutationGeneration[i,mutationPoint1]+1
		   }
		}
	  }
	}
   return(mutationGeneration)
  }