1. A method for determining spatial coincidence between a primary object and a secondary object, the method comprising the steps of, receiving a primary object covariance matrix, receiving a secondary object covariance matrix, receiving a primary object position vector, receiving a secondary object position vector, extending by one dimension the primary object covariance matrix into an extended primary object covariance matrix, inverting the secondary object covariance matrix into an inverted secondary object covariance matrix, subtracting the primary object position vector from the secondary position vector for providing a relative position vector, extending the secondary object inverted covariance matrix by the difference position vector into an extended object B covariance matrix, multiplying the extended secondary object covariance matrix by the extended primary object covariance matrix for providing a product covariance matrix, computing eigenvalues of the product covariance matrix, examining the eigenvalues for indicating the spatial coincidence of primary object and the secondary object, and acting upon the determination of the determining step.