import static java.lang.System.out;

import java.util.*;

import javastat.*;

import javastat.inference.twosamples.*;

import static javastat.util.Argument.*;

import static javastat.util.Output.*;

import javastat.util.*;

/**

*

* <p>Example: class TwoSampMeansZTest.</p>

*/

public class TwoSampMeansZTestExample

{

public static void main(String arg[])

{

double[] testdata1 = {30, 40, 28, 5, 28, 29, 38, 36, 23, 22, 51, 33, 35,

42, 21, 31, 44, 32, 30, 32, 30, 30, 45, 29, 35,

33, 40, 31, 37, 41, 34, 40, 29, 42, 17, 29, 34,

39};

double[] testdata2 = {60, 68, 63, 37, 57, 52, 63, 68, 47, 44, 74, 71,

83, 92, 66, 64, 62, 73, 62, 51, 77, 77, 71, 53,

72, 58, 70, 58, 72, 81, 64, 60, 60, 72, 40, 61,

58, 69};

DataManager dm = new DataManager();

TwoSampMeansZTest testclass1 =

new TwoSampMeansZTest(0.05, 0, "equal", testdata1, testdata2);

double testStatistic = testclass1.testStatistic;

double pValue = testclass1.pValue;

double lowerBound = testclass1.confidenceInterval[0];

double upperBound = testclass1.confidenceInterval[1];

TwoSampMeansZTest testclass2 = new TwoSampMeansZTest();

double[] confidenceInterval = testclass2.confidenceInterval(0.05,

testdata1, testdata2);

testStatistic = testclass2.testStatistic(0, testdata1, testdata2);

pValue = testclass2.pValue(0, "greater", testdata1, testdata2);

Hashtable argument1 = new Hashtable();

argument1.put(ALPHA, 0.05);

argument1.put(NULL_VALUE, 0);

argument1.put(SIDE, "equal");

StatisticalAnalysis testclass3 = new TwoSampMeansZTest(argument1,

testdata1, testdata2).statisticalAnalysis;

testStatistic = (Double) testclass3.output.get(TEST_STATISTIC);

pValue = (Double) testclass3.output.get(PVALUE);

confidenceInterval = (double[]) testclass3.output.get(

CONFIDENCE_INTERVAL);

lowerBound = confidenceInterval[0];

upperBound = confidenceInterval[1];

Hashtable argument2 = new Hashtable();

TwoSampMeansZTest testclass4 =

new TwoSampMeansZTest(argument2, null);

argument2.put(ALPHA, 0.05);

confidenceInterval = testclass4.

confidenceInterval(argument2, testdata1, testdata2);

argument2.put(NULL_VALUE, 0);

testStatistic = testclass4.testStatistic(argument2, testdata1, testdata2);

argument2.put(SIDE, "greater");

pValue = testclass4.pValue(argument2, testdata1, testdata2);

}

}

Results:

The test statistic based on non-null constructor = -13.402

The p-value based on non-null constructor = 0.0

The confidence interval based on non-null constructor = [-35.745 , -26.624]

{TEST_STATISTIC=-13.402, PVALUE=0.0, POINT_ESTIMATE_SE=2.327,

POINT_ESTIMATE=-31.184, CONFIDENCE_INTERVAL=[D@1bf216a}

The test statistic based on null constructor = -13.402

The p-value based on null constructor = 1.0

The confidence interval based on null constructor = [-35.745 , -26.624]

{TEST_STATISTIC=-13.402, PVALUE=1.0,

CONFIDENCE_INTERVAL=[D@12ac982}

See also:

Estimation of the Difference between the Means,

Hypothesis Test about the Difference