summation

summation is a simple Sender/Receiver game where a pair of agents is jointly trained to recognize the a^n b^n grammar. Sender is presented with non-empty sequences of form {a, aabb, abb, ...}, sends a variable-length message to Receiver. In turn, for each sequence, Receiver has to output a binary indicator if the sequence has equal number of as and bs.

Can you guess if Sender will actually count and just pass a decision to Receiver? Or will it simply reproduce the sequence and it is Receiver who answers? Or they invent some in-between code? Does it depend on the parameters?

To get an answer, you can launch the game as follows:

python -m egg.zoo.summation.train --vocab_size=20 --max_n=10  --n_epoch=5 --max_len=10 --batch_size=32 --random_seed=21 --batches_per_epoch=100 --temperature=0.50 --sender_cell=lstm --receiver_cell=lstm --random_seed=21

The game first outputs training scores and then dumps the communication protocol for both agents:

inputs sequence -> message -> Receiever's output (correct label)

In this dump a and b are encoded as 1 and 2. The training is done via Gumbel-Softmax relaxation.

The game accepts the following game-specific parameters:

• max_n -- the maximal value of n in a^nb^n. The maximal length of the input string will be 2 * n + 1
• max_len -- the maximal length of the message between Sender and Receiver
• vocab_size -- the number of unique symbols in the communication vocabulary (inluding <eos>!)
• sender_cell/receiver_cell -- the cells that are used by the agents; can be any of {rnn, gru, lstm}
• n_hidden -- the size of the hidden space for the RNN cells
• embed_dim -- the size of the hidden space for the RNN cells
• lr -- learning rate