10 Year. Morningstar rated the Global Technology Fund among 196, 196, 186 and 144 Technology funds for the overall rating and the 3-, 5-, and 10-year periods (as applicable) ending 02/28/2017, respectively.
Geometrically an eigenvector, corresponding to a real nonzero eigenvalue, points in a direction that is stretched by the transformation and the eigenvalue is the factor by which it is stretched. If the eigenvalue is negative, the direction is reversed.
Hence the multivariate normal distribution is an example of the class of elliptical distributions. The directions of the principal axes of the ellipsoids are given by the eigenvectors of the covariance matrix Ï. The squared relative lengths of the principal axes are given by the corresponding eigenvalues.