asymmetry: The Slide-Vector Model for Multidimensional Scaling of Asymmetric Data
The slide-vector model is provided in this package together with functions for the analysis and graphical display of asymmetry. The slide vector model is a scaling model for asymmetric data. A distance model is fitted to the symmetric part of the data whereas the asymmetric part of the data is represented by projections of the coordinates onto the slide-vector. The slide-vector points in the direction of large asymmetries in the data. The distance is modified in such a way that the distance between two points that are parallel to the slide-vector is larger in the direction of this vector. The distance is smaller in the opposite direction. If the line connecting two points is perpendicular to the slide-vector the difference between the two projections is zero. In this case the distance between the two points is symmetric. The algorithm for fitting this model is derived from the majorization approach to multidimensional scaling.