…(Xu, 1998a; Xu et al., 1995), as well as normalized RBF nets (Moody & Darken, 1989; Nowlan, 1990; Xu et al., 1994) and its extensions (Xu, 1998a), but also new adaptive algorithms for learning and new criteria for deciding the number of hidden units, experts, and basis functions (Xu, 1998a, 2001b).