test.KKurt {mnt} | R Documentation |
Test of normality based on Koziols measure of multivariate sample kurtosis
Description
Computes the multivariate normality test based on the invariant measure of multivariate sample kurtosis due to Koziol (1989).
Usage
test.KKurt(data, MC.rep = 10000, alpha = 0.05)
Arguments
data |
a n x d matrix of d dimensional data vectors. |
MC.rep |
number of repetitions for the Monte Carlo simulation of the critical value |
alpha |
level of significance of the test |
Details
Multivariate sample kurtosis due to Koziol (1989) is defined by
\widetilde{b}_{n,d}^{(2)}=\frac{1}{n^2}\sum_{j,k=1}^n(Y_{n,j}^\top Y_{n,k})^4,
where Y_{n,j}=S_n^{-1/2}(X_j-\overline{X}_n)
, j=1,\ldots,n
, are the scaled residuals, \overline{X}_n
is the sample mean and S_n
is the sample covariance matrix of the random vectors X_1,\ldots,X_n
. To ensure that the computation works properly
n \ge d+1
is needed. If that is not the case the test returns an error. Note that for d=1
, we have a measure proportional to the squared sample kurtosis.
Value
a list containing the value of the test statistic, the approximated critical value and a test decision on the significance level alpha
:
$Test
name of the test.
$Test.value
the value of the test statistic.
$cv
the approximated critical value.
$Decision
the comparison of the critical value and the value of the test statistic.
References
Koziol, J.A. (1989), A note on measures of multivariate kurtosis, Biom. J., 31:619-624.
See Also
Examples
test.KKurt(MASS::mvrnorm(50,c(0,1),diag(1,2)),MC.rep=500)