Hi Simon, thanks for replying back. The condition can be put forth as follows. Suppose that I have a neural network called DNN (short for decision neural network). Now, if for data point x, the output of DNN, i.e. the quantity DNN(x) is positive, then I decide to use NN1 (short for neural network 1), while if DNN(x) is negative, I decide to use NN2.