Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the Use and Misuse of Absorbing States in Multi-agent Reinforcement
  Learning   The creation and destruction of agents in cooperative multi-agent
reinforcement learning (MARL) is a critically under-explored area of research.
Current MARL algorithms often assume that the number of agents within a group
remains fixed throughout an experiment. However, in many practical problems, an
agent may terminate before their teammates. This early termination issue
presents a challenge: the terminated agent must learn from the group's success
or failure which occurs beyond its own existence. We refer to propagating value
from rewards earned by remaining teammates to terminated agents as the
Posthumous Credit Assignment problem. Current MARL methods handle this problem
by placing these agents in an absorbing state until the entire group of agents
reaches a termination condition. Although absorbing states enable existing
algorithms and APIs to handle terminated agents without modification, practical
training efficiency and resource use problems exist.
  In this work, we first demonstrate that sample complexity increases with the
quantity of absorbing states in a toy supervised learning task for a fully
connected network, while attention is more robust to variable size input. Then,
we present a novel architecture for an existing state-of-the-art MARL algorithm
which uses attention instead of a fully connected layer with absorbing states.
Finally, we demonstrate that this novel architecture significantly outperforms
the standard architecture on tasks in which agents are created or destroyed
within episodes as well as standard multi-agent coordination tasks.

8
The categories of this paper are: hep-ex
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
9
The categories of this paper are: nlin