The update gate helps to decide what information from the previous time step, , can be taken forward to the next time step, . It is basically a combination of an input gate and a forget gate, which we learned about in LSTM cells. Similar to the gates about the LSTM cell, the update gate is also regulated by the sigmoid function.
The update gate, , at time step is expressed as follows:
Here, the following applies:
- is the input-to-hidden ...