/*
GeoGebra - Dynamic Mathematics for Everyone
http://www.geogebra.org
This file is part of GeoGebra.
This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation.
*/
package org.geogebra.common.kernel.statistics;
import org.apache.commons.math3.distribution.NormalDistribution;
import org.geogebra.common.kernel.Construction;
import org.geogebra.common.kernel.algos.AlgoElement;
import org.geogebra.common.kernel.commands.Commands;
import org.geogebra.common.kernel.geos.GeoElement;
import org.geogebra.common.kernel.geos.GeoList;
import org.geogebra.common.kernel.geos.GeoNumeric;
/**
*
*
* @author G. Sturr
*/
public class AlgoZProportion2Estimate extends AlgoElement {
private GeoNumeric proportion, n, proportion2, n_2, level; // input
private GeoList result; // output
private double se;
private double me;
/**
* @param cons
* @param label
* @param proportion
* @param n
* @param proportion2
* @param n_2
* @param level
*/
public AlgoZProportion2Estimate(Construction cons, String label,
GeoNumeric proportion, GeoNumeric n, GeoNumeric proportion2,
GeoNumeric n_2, GeoNumeric level) {
this(cons, proportion, n, proportion2, n_2, level);
result.setLabel(label);
}
/**
* @param cons
* @param proportion
* @param n
* @param proportion2
* @param n_2
* @param level
*/
public AlgoZProportion2Estimate(Construction cons, GeoNumeric proportion,
GeoNumeric n, GeoNumeric proportion2, GeoNumeric n_2,
GeoNumeric level) {
super(cons);
this.proportion = proportion;
this.n = n;
this.proportion2 = proportion2;
this.n_2 = n_2;
this.level = level;
result = new GeoList(cons);
setInputOutput(); // for AlgoElement
compute();
}
@Override
public Commands getClassName() {
return Commands.ZProportion2Estimate;
}
@Override
protected void setInputOutput() {
input = new GeoElement[5];
input[0] = proportion;
input[1] = n;
input[2] = proportion2;
input[3] = n_2;
input[4] = level;
setOnlyOutput(result);
setDependencies(); // done by AlgoElement
}
/**
* @return {lower confidence limit, upper confidence limit}.
*/
public GeoList getResult() {
return result;
}
/**
* @return margin of error
*/
public double getME() {
return me;
}
/**
* @return standard error
*/
public double getSE() {
return se;
}
@Override
public final void compute() {
double n1 = n.getDouble();
double phat1 = proportion.getDouble();
double n2 = n_2.getDouble();
double phat2 = proportion2.getDouble();
double cLevel = level.getDouble();
NormalDistribution normalDist = new NormalDistribution(0, 1);
double critZ = 0;
try {
critZ = normalDist.inverseCumulativeProbability((1 - cLevel) / 2);
} catch (Exception e) {
result.setUndefined();
return;
}
double stat = phat1 - phat2;
se = Math.sqrt(phat1 * (1 - phat1) / n1 + phat2 * (1 - phat2) / n2);
double z = Math.abs(critZ);
me = z * se;
// put these results into the output list
result.clear();
result.addNumber(stat - me, null);
result.addNumber(stat + me, null);
}
}