“…In order to deliver satisfactory results, finding a good distance metric for the problem at hand often plays a very crucial role. As such, metric learning (Xing et al, 2002) has received much attention in the research community (Baxter, 1997;Xing et al, 2002;Chang & Yeung, 2004;Weinberger et al, 2005;Davis et al, 2007;Yeung & Chang, 2007;Chen et al, 2007;Davis & Dhillon, 2008;Yeung et al, 2008;Zhan et al, 2009;Jin et al, 2009). Many metric learning methods have been proposed.…”