StatBean Name: Correlations

Purpose: Computes product-moment and rank correlation coefficients between pairs of numeric columns.

DataSource: Any.

Read/Write Properties

Name	Type	Description	Possible Values	Default Value
columnNames	String array	The names of the columns to be analyzed.	One or more strings.	{""}
computeRankCorrelations	boolean	Whether to compute rank correlations as well as product-moment correlations.	true,false	false
missingValueExclusion	String	The method for handling records which contain missing values.	"Columnwise","Casewise", "Tablewise"	"Columnwise"

Other Public Methods

Name	Description	Arguments	Return Value
double getCorrelation(int columnNumber,int rowNumber)	Returns product-moment correlation.	Column number, row number (0 origin).	Estimated correlation, or missingValueCode if n<2.
double getPValue(int columnNumber,int rowNumber)	Returns P-value for two-sided test of null hypothesis that correlation = 0.	Column number, row number (0 origin).	P-value.
double getRankCorrelation(int columnNumber,int rowNumber)	Returns Spearman rank correlation.	Column number, row number (0 origin).	Estimated correlation, or missingValueCode if n<2.
double getRankPValue(int columnNumber,int rowNumber)	Returns P-value for two-sided test of null hypothesis that rank correlation = 0.	Column number, row number (0 origin).	P-value.
int getNumberOfVariables()	Returns number of columns.	None.	Number of columns (and rows).
int getSampleSize(int columnNumber,int rowNumber)	Returns number of pairs of data values used to calculate correlation.	Column number, row number (0 origin).	n

Code Sample

//create a filedatasource bean
FileDataSource fileDataSource1 = new FileDataSource();

//set the file name
fileDataSource1.setFileName("c:\\statbeans\\samples\\cardata.txt");

//create a calculation bean
Correlations correlations1 = new Correlations();

//set missing value handling
correlations1.setMissingValueExclusion("Columnwise");

//set the column names
String[] temp = new String[5];
temp[0] = new String("mpg");
temp[1] = new String("weight");
temp[2] = new String("horsepower");
temp[3] = new String("displace");
temp[4] = new String("price");
correlations1.setColumnNames(temp);

//create a table bean
CorrelationsTable correlationsTable1 = new CorrelationsTable();

//set table size
correlationsTable1.setScaleRowsToFit(false);
correlationsTable1.setScaleColumnsToFit(false);
correlationsTable1.setNumberOfRowsInDisplay(15);
correlationsTable1.setNumberOfColumnsInDisplay(5);

//prevent some rows and columns from scrolling
correlationsTable1.setHoldRows(3);
correlationsTable1.setHoldColumns(1);

//add the table to the display panel
add(correlationsTable1);

//register the calculation StatBean as a listener to the datasource
fileDataSource1.addDataChangeListener(correlations1.listenerForDataChange);

//register the table StatBean as a listener to the calculation StatBean
correlations1.addDataChangeListener(correlationsTable1.listenerForDataChange);

//read the file
fileDataSource1.readData();

//notify all listeners
fileDataSource1.updateListeners();