an improved approximation algorithm for mms allocation

An Improved Approximation Algorithm For MMS Allocation Input Output - PowerPoint PPT Presentation

An Improved Approximation Algorithm For MMS Allocation Input Output Agents: = {1,2, , } A 3/4-Maximin Share (MMS) allocation % , & , , ' where Indivisible items: = {1, 2, , } ( )


  1. An Improved Approximation Algorithm For MMS Allocation Input Output š Agents: 𝑂 = {1,2, … , π‘œ} š A 3/4-Maximin Share (MMS) allocation 𝐡 % , 𝐡 & , … , 𝐡 ' where š Indivisible items: 𝑁 = {1, 2, … , 𝑛} ( ) 𝑁𝑁𝑇 ! (aka maximin value) 𝑀 ! (𝐡 ! ) β‰₯ ⁄ š Additive valuation functions 𝑀 ! 𝑇 = βˆ‘ "∈$ 𝑀 !" for all 𝑗 ∈ 𝑂 , 𝑇 βŠ† 𝑁 1

  2. MMS value / partition / allocation MMS allocation: 🍏 🍍 πŸ‘ 🍎 πŸ₯¦ 𝑀 ! (𝐡 ! ) β‰₯ 𝑁𝑁𝑇 ! Agents\items πŸ‘ͺ 3 1 2 5 4 πŸ‘© 4 4 5 3 2 πŸ‘ͺ 🍎πŸ₯¦ 🍍 🍍 πŸ‘© 🍍 🍏 πŸπŸ‘ πŸ‘ͺ πŸ‘© 🍏 πŸ₯¦ πŸ‘πŸŽ 🍎πŸ₯¦ 🍎πŸ₯¦ πŸπŸ‘ value 7 8 value 9 9 MMS allocation might MMS value 7 MMS value 9 not exist, but 3/4-MMS 2 allocation always exist Finding MMS value is hard!

  3. Algorithm Big Picture To show the existence of 3/4-MMS allocation: We assume MMS i is known for all 𝑗 ⟹ Scale valuations such that MMS i = 1 for all 𝑗 β‡’ 𝑀 ! 𝑁 β‰₯ π‘œ š Step 1: Valid Reductions š Exist 𝑇 βŠ† 𝑁 and 𝑗 βˆ— ∈ 𝑂 such that 𝑀 ! βˆ— (𝑇) β‰₯ ( ⁄ % (𝑁) # $ )𝑁𝑁𝑇 ! βˆ— %&' (𝑁\S) β‰₯ 𝑁𝑁𝑇 ! % (𝑁) for all 𝑗 β‰  𝑗 βˆ— š 𝑁𝑁𝑇 ! š Step 2: Generalized Bag Filling 3

  4. Results Strongly Polynomial- time Algorithm for 3/4-MMS allocation n / ) M ( v i Existence of 3/4- MMS allocation More careful analysis MMS values are known Existence of PTAS for (3/4+1/(12n))- (3/4+1/(12n))-MMS PTAS MMS allocation allocation 4 MMS values are known

Recommend


More recommend