Waze and Network Traffic
https://www.lamag.com/citythinkblog/waze-los-angeles-neighborhoods/
https://la.curbed.com/2018/10/26/18024720/waze-street-safety-traffic-short-cuts
These two articles describe the impact of the navigation app Waze in LA, a city famous for its traffic. When the Waze navigation app was first released in 2014, it shortened travel time by providing users with shortcuts through side streets, rather than using major roads to navigate LA. However, Waze’s novelty and effectiveness has declined since its release in 2014. Recent reports from LA sources state that the app has created congestion on residential streets in an attempt to divert users from major roads and cut down on travel time. Travel times have also increased as more people began to use Waze since its release. Taking these routes through residential streets also poses safety concerns with increased levels of traffic, as these roads may be too narrow, steep, or twisted to accommodate larger vehicles, speeding drivers, and higher volumes of congestion.
This situation in LA relates to our discussion of game theory and network traffic from the past few lectures, particularly relating to Nash equilibriums and Braess’s Paradox. The app is able to collect data from users all around the city and uses its algorithm to decide the fastest routes for users. This overall balances users along all possible routes in LA, allowing traffic patterns to reach a Nash equilibrium. However, this does not necessarily result in the shortest possible travel times for every individual driver. The article also relates to Braess’s Paradox, which describes that adding one or more roads to a network can increase travel time and impede overall traffic flow. In this real-world situation, more roads were not physically added to the LA, but rather the Waze app identified new paths and routes for users to take. The Waze app is popular in LA, and this effectively increased the number of roads commonly travelled in the LA traffic network. Many roads were quiet residential roads with little traffic before identified by the Waze app as time-saving shortcuts. Waze demonstrates Braess’s Paradox because as more roads were added to the network and traveled by users, and more people began to use Waze, travel time and traffic actually increased on LA roads. Although this real-world example demonstrates the power of algorithms and game theory in navigation, it also showcases their weaknesses. For example, the Waze app did not take into account construction along these roads, lower speed limits, or how narrow or steep these roads were that had been identified as “shortcuts,” resulting in unsafe conditions, congestion, and accidents. Overall, traffic in LA and the Waze app demonstrate key concepts of game theory as well as Braess’s Paradox.