Artificial Neural Network

1). What would happen if Artificial Neural Networks (ANN) did not have any bias (fixed input)? For instance, suppose that 'y' must be 5 when all inputs are 0.

2). What are the main similarities and differences between the functions 'logsig' and 'tanh'?

3). Indicate whether the next statements are true or false and explain:

• When the neutrons of an artificial neural network (ANN) use the LOGSIG function, the output values of the network cannot exceed a value of one no matter what input is applied tot he network. A value outside the range [0 1] is impossible to attain at the output of the ANN. If the required range is bigger than zero to one, then the output signal must be scaled appropriately.
• When the neutrons of an artificial neural network (ANN) use the TANH function, it is very important to note that the output signal is limited to the range from -1 to 1. The 'tanh' function has a shape very similar to the shape of the 'logsig' function. However, the lower range for the 'logsig' function is zero when compared with the lower range of the 'tanh' which is -1.