# Data-Driven Models of Selfish Routing: Why Price of Anarchy Does Depend on Network Topology

@article{Benita2020DataDrivenMO, title={Data-Driven Models of Selfish Routing: Why Price of Anarchy Does Depend on Network Topology}, author={Francisco Benita and Vittorio Bil{\`o} and Barnab{\'e} Monnot and Georgios Piliouras and Cosimo Vinci}, journal={ArXiv}, year={2020}, volume={abs/2009.12871} }

We investigate traffic routing both from the perspective of real world data as well as theory. First, we reveal through data analytics a natural but previously uncaptured regularity of real world routing behavior. Agents only consider, in their strategy sets, paths whose free-flow costs (informally their lengths) are within a small multiplicative $(1+\theta)$ constant of the optimal free-flow cost path connecting their source and destination where $\theta\geq0$. In the case of Singapore…

## 5 Citations

### Routing Games in the Wild: Efficiency, Equilibration, Regret, and a Price of Anarchy Bound via Long Division

- Computer ScienceACM Trans. Economics and Comput.
- 2022

A new metric, the Free-flow Index (FFI), is introduced, which reflects the inefficiency resulting from system congestion and is the first model-free computation of an upper bound to the price of anarchy utilizing only real world measurements of traffic data.

### The Impact of Selfish Behavior in Load Balancing Games

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This work investigates whether better performance are possible when restricting to load balancing games in which players can only choose among single resources, and proves that, under mild assumptions on the latency functions, improvements on the performance of approximate pure Nash equilibria are possible for load balancinggames with weighted and symmetric players.

### Nash Social Welfare in Selfish and Online Load Balancing

- Computer ScienceICTCS
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This work provides tight bounds on the price of anarchy of pure Nash equilibria and on the competitive ratio of the greedy algorithm under very general latency functions, including polynomial ones and proves that the greedy strategy is optimal, as it matches the performance of any possible online algorithm.

### General Opinion Formation Games with Social Group Membership

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Modeling how agents form their opinions is of paramount importance for designing marketing and electoral campaigns. In this work, we present a new framework for opinion formation which generalizes…

### Weighted Stackelberg Algorithms for Road Traffic Optimization

- Computer ScienceSIGSPATIAL/GIS
- 2021

A weighted version of the Stackelberg routing problem in which the delay experienced by non-users of the platform is discounted by some parameter β < 1, and natural algorithms for this problem are studied and provable guarantees in the form of constant approximation ratios are provided.

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