Test of Structure of a Covariance Matrix given by Nagao 1973

Test of Structure of a Covariance Matrix given by Nagao 1973

Nagao1973(x, Sigma = "identity", ...)

Arguments

x	data
Sigma	Population covariance matrix
...	other options passed to covTest method

Value

A list with class "htest" containing the following components:

statistic	the value of equality of covariance test statistic
parameter	the degrees of freedom for the chi-squared statistic
p.value	the p=value for the test
estimate	the estimated covariances if less than 5 dimensions
null.value	the specified hypothesized value of the covariance difference
alternative	a character string describing the alternative hyposthesis
method	a character string indicating what type of equality of covariance test was performed

Details

The structureCovariances function is a wrapper function that formats the data for the specific covTest functions.

References

Nagao, H. (1973). On Some Test Criteria for Covariance Matrix. The Annals of Statistics, 1(4), 700-709

Examples

Nagao1973(as.matrix(iris[1:50, 1:3]))
#> 
#> 	Nagao 1973 Test of Covariance Matrix Structure
#> 
#> data:  
#> Chi Squared = 61.532, df = 6, p-value = 2.197e-11
#> alternative hypothesis: true difference between the Sample Covariance Matrix and the Null Covariance Matrix Structure is not equal to 0
#> sample estimates:
#>              Sepal.Length Sepal.Width Petal.Length
#> Sepal.Length   0.12424898  0.09921633   0.01635510
#> Sepal.Width    0.09921633  0.14368980   0.01169796
#> Petal.Length   0.01635510  0.01169796   0.03015918
#>