WMMS implies EFX for two agents

Dependencies:

  1. Fair division
  2. Maximin share allocations
  3. EFX
  4. WMMS-sat and envious of everyone implies EFX-sat

Consider a fair division instance $([2], [m], V, w)$ of indivisible items (where each agent $i$ has entitlement $w_i$). Suppose an allocation $A$ is WMMS-fair to agent 1. Then $A$ is also EFX-fair to agent 1 if one of these conditions hold:

  1. The items are goods to agent 1.
  2. $v_1$ is additive and $w_1 ≤ w_2$.

Proof

If agent 1 doesn't envy agent 2, she is EFX-satisfied. Otherwise, she is EFX-satisfied because of mms-and-all-envy.html.

Dependency for:

  1. MMS implies MXS

Info:

Transitive dependencies:

  1. /sets-and-relations/countable-set
  2. /analysis/sup-inf
  3. σ-algebra
  4. Set function
  5. Fair division
  6. Envy-freeness
  7. Maximin share of a set function
  8. Maximin share allocations
  9. Submodular function
  10. EFX
  11. WMMS-sat and envious of everyone implies EFX-sat