StatBean Name: HypothesisTests

Purpose: Performs hypothesis tests for means, medians, standard deviations, proportions, and rates.

DataSource: Any.

Read/Write Properties

Name	Type	Description	Possible Values	Default Value
alpha	double	Type I Error, as a percentage.	0.0001-50.0	5.0
alternativeHypothesis	String	Type of alternative hypothesis.	"Not equal", "Less than", "Greater than"	"Not equal"
assumeEqualSigmas	boolean	Whether to assume equal sigmas if comparing 2 means.	true,false	true
class1Name	String	Name for first class to be used in title.	Any string.	""
class2Name	String	Name for second class to be used in title.	Any string.	""
missingValueExclusion	String	The method for handling records which contain missing values.	"Columnwise","Casewise", "Tablewise"	"Columnwise"
nullHypothesis	double	The value of the null hypothesis.	Any double.	1.0
parameterOfInterest	String	Parameter to be tested.	"Mean", "Median", "Sigma", "Proportion", "Rate", "Difference of Means", "Ratio of Sigmas", "Difference of Proportions", "Difference of Rates", "Difference of Medians", "Difference of Distributions"	"Mean"
sample1VariableName	String	The name of the column with data values for the first sample (if any).	Any string.	""
sample2VariableName	String	The name of the column with data values for the first sample (if any).	Any string.	""
sample1Mean	double	The mean of the first sample.	Any double.	Missing.
sample2Mean	double	The mean of the second sample.	Any double.	Missing.
sample1Proportion	double	The proportion for the first sample.	0.0-1.0	Missing.
sample2Proportion	double	The proportion for the second sample.	0.0-1.0	Missing.
sample1Rate	double	The rate for the first sample.	0+	Missing.
sample2Rate	double	The rate for the second sample.	0+	Missing.
sample1Sigma	double	The standard deviation of the first sample.	>0	Missing.
sample2Sigma	double	The standard deviation of the second sample.	>0	Missing.
sample1Size	int	The number of observations in the first sample.	1+	0
sample2Size	int	The number of observations in the second sample.	1+	0
signTest	boolean	Whether to use sign test rather than signed rank test if comparing 2 medians.	true,false	false

Other Public Methods

Name	Description	Arguments	Return Value
double getPValue()	Returns the P-Value for the test.	None	P-Value
double getTestStatistic()	Returns the value of the test statistic.	None	Test statistic

Notes

1. For tests involving means or standard deviations, the statistics may either be supplied directly through methods such as setSample1Size or calculated from the data by specifying variable names. If specifying statistics directly, call calculateStatistics(null). If providing data, make the HypothesisTests bean a listener for a StatDataSource.

2. For tests involving medians, the data must be provided.

3. For tests involving proportions or rates, the statistics must be provided and any data is ignored.

Code Sample

//create a calculation bean
HypothesisTests hypothesistests1 = new STATBEANS.HypothesisTests();

//set the parameter to be tested
hypothesistests1.setParameterOfInterest("Sigma");

//set the sample statistics
hypothesistests1.setSample1Size(30);
hypothesistests1.setSample1Sigma(8.0);

//set the hypotheses to be tested
hypothesistests1.setNullHypothesis(10.0);

//set up a table to display results
hypothesisTestsTable hypothesistestsTable1 = new STATBEANS.HypothesisTestsTable();

//add the table to the display
add(hypothesistestsTable1);

//create a plot bean
HypothesisTestsPlot hypothesistestsPlot1 = new STATBEANS.HypothesisTestsPlot();

//add the plot to the display
add(hypothesistestsPlot1);

//make the table and plot beans listeners for changes in the calculation bean
hypothesistests1.addDataChangeListener(hypothesistestsTable1.listenerForDataChange);
hypothesistests1.addDataChangeListener(hypothesistestsPlot1.listenerForDataChange);

//instruct the calculation bean to compute the probabilities
hypothesistests1.calculateStatistics(null);