Computes the multivariate normality test based on the invariant measure of multivariate sample kurtosis due to Koziol (1989).
test.KKurt(data, MC.rep = 10000, alpha = 0.05)
a n x d matrix of d dimensional data vectors.
number of repetitions for the Monte Carlo simulation of the critical value
level of significance of the test
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.
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.
Koziol, J.A. (1989), A note on measures of multivariate kurtosis, Biom. J., 31:619-624.
# NOT RUN {
test.KKurt(MASS::mvrnorm(50,c(0,1),diag(1,2)),MC.rep=500)
# }
Run the code above in your browser using DataLab