Bertrand

BertrandMatrix is a repeated 2-player price-competition game implemented in masa.envs.multiagent.matrix.bertrand.

Overview

• Class: BertrandMatrix

• Metadata name: bertrand_matrix_v0

• Agents: player_0, player_1

• Actions: High=0, Low=1

• Default payoffs: T=8, R=5, S=0, P=0

The stage game is:

• High, High -> (R, R)

• High, Low -> (S, T)

• Low, High -> (T, S)

• Low, Low -> (P, P)

Safety Semantics

The environment labels Low, Low as a price war. Its label_fn emits price_war and unsafe, and the default cost_fn returns a binary cost of 1 whenever unsafe is present.

Observation Channels

Observations are binary channels representing the previous joint action and whether the last round ended in a price war:

• player_0_high

• player_0_low

• player_1_high

• player_1_low

• price_war