org.statcato.statistics.inferential

Class CIOnePopVar

java.lang.Object

org.statcato.statistics.inferential.CIOnePopVar

public class CIOnePopVar
extends java.lang.Object

Confidence interval class for one population variance.

Since:

1.0

Constructor Summary

Constructors

Constructor and Description
CIOnePopVar(double confidenceLevel, int n, double variance) Constructor.

Method Summary

Modifier and Type	Method and Description
double	lowerLimit() Returns the lower limit of the confidence interval.
java.lang.String	stdevCI() Returns a string representing the confidence interval of the standard deviation (lower limit, upper limit);
java.lang.String	toString() Returns a string representing the confidence interval of the variance (lower limit, upper limit).
double	upperLimit() Returns the upper limit of the confidence interval.

Methods inherited from class java.lang.Object

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

Constructor Detail

CIOnePopVar

public CIOnePopVar(double confidenceLevel,
                   int n,
                   double variance)

Constructor.

Parameters:

confidenceLevel - confidence level, between 0 and 1

n - sample size

variance - sample variance

Method Detail

lowerLimit

public double lowerLimit()

Returns the lower limit of the confidence interval. (n-1)*s^2 / XR^2, where XR is the inverse cumulative probability of the chi-square distribution at 1 - alpha/2 (alpha is the signifiance level).

Returns:

lower limit

upperLimit

public double upperLimit()

Returns the upper limit of the confidence interval. (n-1)*s^2 / XL^2, where XL is the inverse cumulative probability of the chi-square distribution at alpha/2 (alpha is the significance level).

Returns:

upper limit

toString

public java.lang.String toString()

Returns a string representing the confidence interval of the variance (lower limit, upper limit).

Overrides:

toString in class java.lang.Object

Returns:

string

stdevCI

public java.lang.String stdevCI()

Returns a string representing the confidence interval of the standard deviation (lower limit, upper limit);

Returns:

string