2.13.2.6 vartest1(Pro)

1 Brief Information
2 Additional Information
3 Command Line Usage
4 X-Function Execution Options
5 Variables
6 Description
7 Examples
8 Algorithm
9 References
10 Related X-Functions

Brief Information

Chi-squared variance test

Additional Information

This feature is for OriginPro only.

Minimum Origin Version Required: 8.0 SR4

Command Line Usage

1. vartest1 irng:=Col(A);

2. vartest1 irng:=Col(A) var:=2.0 tail:=2;

3. vartest1 irng:=Col(A) var:=2.0 alpha:=0.05;

4. vartest1 irng:=Col(A) var:=2.0 prob:=p;

X-Function Execution Options

Please refer to the page for additional option switches when accessing the x-function from script

Variables

Display Name	Variable Name	I/O and Type	Default Value	Description
Input	irng	Input Range	<active>	Specify the input data range
Test Variance	var	Input double	1	The hypothetical variance value
Tail	tail	Input int	two	Alternative hypothesis specified by the tail. (Suppose S is the test variance.) Option list two:Two Tailed H0: Variance <> S Tow tailed test to determine if the sample variance is different from the given hypothetical variance upper:Upper Tailed H0: Variance > S Upper tailed test to determine if the sample variance is larger than the given hypothetical variance lower:Lower Tailed H0: Variance < S Lower tailed test to determine if the sample variance is less than the given hypothetical variance
Significance Level	alpha	Input double	0.05	Set the significance level of the test
Statistics	stat	Output double	<unassigned>	Value of the F-test statistic
Degrees of Freedom	df	Output double	<unassigned>	Degrees of freedom of the F-test
P-value	prob	Output double	<unassigned>	Associated p-value of the test. If the p-value is less than the value of alpha, the null hypothesis should be rejected
Lower Confidence Limit	lcl	Output double	<unassigned>	Lower confidence limit of sample variance
Upper Confidence Limit	ucl	Output double	<unassigned>	Upper confidence limit of sample variance

Description

This function performs a chi-squared variance test, to determine whether or not the sample from a normal distribution could have a given hypothetical variance value.

This function is script accessing only, and the test is the same as One Sample Test for Variance on the menu.

Examples

1. Import vartest1.dat on the \Sample\Statistics\ folder.

2. Use the default setting, type:

vartest1 irng:=Col(A)

3. If you want to know if the variance of the data is equal to a specified value, e.g. 0.015, you can use the command:

vartest1 irng:=Col(A) var:=0.015

Algorithm

This function is used to perform one sample test for variance from LabTalk Script. Please refer to Algorithm of One-Sample Test for Variance for the detail algorithms.

References

Snedecor, George W. and Cochran, William G. (1989), Statistical Methods, Eighth Edition, Iowa State University Press.

Related X-Functions

vartest2, ttest2, ttest1