org.statcato.statistics.inferential

Class CI2PopProp

java.lang.Object

org.statcato.statistics.inferential.ConfidenceInterval

org.statcato.statistics.inferential.CI2PopProp

public class CI2PopProp
extends ConfidenceInterval

Confidence interval class for two population proportions.

Since:

1.0

Constructor Summary

Constructors

Constructor and Description
CI2PopProp(double confidenceLevel, int n1, int n2, double p1, double p2) Constructor

Method Summary

Modifier and Type	Method and Description
double	criticalValue() Returns the critical value corresponding to the given confidence level.
double	marginOfError() Returns the margin of error.

Methods inherited from class org.statcato.statistics.inferential.ConfidenceInterval

center, lowerLimit, toString, upperLimit

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

CI2PopProp

public CI2PopProp(double confidenceLevel,
                  int n1,
                  int n2,
                  double p1,
                  double p2)

Constructor

Parameters:

confidenceLevel - confidence level, between 0 and 1

n1 - sample size 1

n2 - sample size 2

p1 - sample proportion 1

p2 - sample proportion 2

Method Detail

marginOfError

public double marginOfError()

Returns the margin of error. E = z_(alpha/2) * sqrt(p1*q1/n1 + p2*q2/n2)

Specified by:

marginOfError in class ConfidenceInterval

Returns:

margin of error

criticalValue

public double criticalValue()

Returns the critical value corresponding to the given confidence level. Uses the z distribution to find z_(alpha/2), where alpha is the significance level (1 - confidence level).

Specified by:

criticalValue in class ConfidenceInterval

Returns:

critical value