Why VNEs?

While adding VPEs improved the quality of directed NE in terms of link-prediction accuracy, the accuracy gain was larger when VNEs were added instead. Adding VPEs in addition to VNEs resulted in marginal additional gains. The results show that VNEs provide information more useful to directed NE methods than VPEs; furthermore, we suspect that the information inherent in VNEs is more difficult for directed NE methods to utilize (than that in VPEs) unless it is explicitly provided in the form of VEs.