# Achieving Target Equilibria in Network Routing Games without Knowing the Latency Functions

@article{Bhaskar2014AchievingTE, title={Achieving Target Equilibria in Network Routing Games without Knowing the Latency Functions}, author={Umang Bhaskar and Katrina Ligett and Leonard J. Schulman and Chaitanya Swamy}, journal={2014 IEEE 55th Annual Symposium on Foundations of Computer Science}, year={2014}, pages={31-40} }

The analysis of network routing games typically assumes, right at the onset, precise and detailed information about the latency functions. Such information may, however, be unavailable or difficult to obtain. Moreover, one is often primarily interested in enforcing a desirable target flow as the equilibrium by suitably influencing player behavior in the routing game. We ask whether one can achieve target flows as equilibria without knowing the underlying latency functions. Our main result gives…

## 31 Citations

### Computing Optimal Tolls in Routing Games without Knowing the Latency Functions

- Computer ScienceArXiv
- 2015

It is shown that in this model, it is impossible to obtain optimal tolls, but if the oracle is augmented so that it returns the total latency of the equilibrium flow induced by the tolls in addition to the flow itself, then the required tolls can be computed with a polynomial number of queries.

### Fundamental limits of locally-computed incentives in network routing

- Economics, Computer Science2017 American Control Conference (ACC)
- 2017

It is asked if it is possible to positively influence social behavior with no risk of unintentionally incentivizing pathological behavior, and a type of pathological network in which all locally-computed tolling functions can cause perverse incentives for heterogeneous price-sensitive user populations is exhibited.

### The benefit of perversity in taxation mechanisms for distributed routing

- Computer Science, Economics2017 IEEE 56th Annual Conference on Decision and Control (CDC)
- 2017

There is a tradeoff between perversity and efficiency: even on parallel networks, a taxation mechanism that optimizes worst-case performance does so by creating perverse incentives on some networks.

### Can Taxes Improve Congestion on All Networks?

- EconomicsIEEE Transactions on Control of Network Systems
- 2020

It is shown that if networks are sufficiently complex and populations sufficiently diverse, perverse incentives cannot be systematically avoided: Any taxation mechanism that improves outcomes on one network must necessarily degrade them on another.

### Optimal mechanisms for robust coordination in congestion games

- Economics2015 54th IEEE Conference on Decision and Control (CDC)
- 2015

This paper studies the application of taxes to a network-routing game, and it is shown that it is possible to design taxes that guarantee that network flows are arbitrarily close to optimal flows, despite the fact that agents' tax-sensitivities are unknown to us.

### Wardrop Equilibrium in Discrete-Time Selfish Routing With Time-Varying Bounded Delays

- EconomicsIEEE Transactions on Automatic Control
- 2021

A multicommodity, discrete-time, distributed, and noncooperative routing algorithm is proved to converge to an equilibrium in the presence of heterogeneous, unknown, time-varying but bounded delays.

### Inducing Approximately Optimal Flow Using Truthful Mediators

- EconomicsEC
- 2015

This work shows how to design a weak mediator such that it is an asymptotic ex-post Nash equilibrium for all players to truthfully report their types to the mediator and faithfully follow its suggestion, and that when they do, they end up playing a nearly optimal flow.

### Avoiding perverse incentives in affine congestion games

- Economics, Computer Science2016 IEEE 55th Conference on Decision and Control (CDC)
- 2016

It is proved that if some network users are unresponsive to tolls, any taxation mechanism that does not depend on network structure can create perverse incentives, and it is shown that a small amount of additional information can mitigate this negative result.

### The Robustness of Marginal-Cost Taxes in Affine Congestion Games

- Computer ScienceIEEE Transactions on Automatic Control
- 2017

This work presents a simple setting in which scaled marginal-cost tolls can be guaranteed to provide significant efficiency improvements over the un-tolled case, even if the toll-sensitivities of the users are unknown.

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