test.MAKurt {mnt} | R Documentation |
Test of normality based on multivariate kurtosis in the sense of Malkovich and Afifi
Description
Computes the multivariate normality test based on the invariant measure of multivariate sample kurtosis due to Malkovich and Afifi (1973).
Usage
test.MAKurt(data, MC.rep = 10000, alpha = 0.05, num.points = 1000)
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 |
num.points |
number of points distributed uniformly over the sphere for approximation of the maximum on the sphere. |
Details
Multivariate sample skewness due to Malkovich and Afifi (1973) is defined by
b_{n,d,M}^{(1)}=\max_{u\in \{x\in\mathbf{R}^d:\|x\|=1\}}\frac{\left(\frac{1}{n}\sum_{j=1}^n(u^\top X_j-u^\top \overline{X}_n )^3\right)^2}{(u^\top S_n u)^3},
where \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.
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.
$param
number of points used in approximation.
$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
Malkovich, J.F., and Afifi, A.A. (1973), On tests for multivariate normality, J. Amer. Statist. Ass., 68:176-179.
Henze, N. (2002), Invariant tests for multivariate normality: a critical review, Statistical Papers, 43:467-506.
See Also
Examples
test.MAKurt(MASS::mvrnorm(10,c(0,1),diag(1,2)),MC.rep=100)