Team and Background

Team

Background

Modern cities are extraordinarily complex centers of population that present a setting for infinite social, economic, environmental, and logistical systems to optimize. This setting makes urban planning a prime domain for the mathematical and computational problems explored in spatial optimization and systems engineering. As urbanization continues to be a global trend, approaches to urban planning in the US have led to cities that are not justly designed in that, among other factors, they are inconveniently planned for the majority of their population, primarily socially and economically marginalized groups. Accessibility to public transportation is an extremely important feature of the modern city; it can be a deciding factor when it comes to accessing employment, housing, and important resources like daycare services and groceries.

In St Louis, accessibility to public transportation is an ongoing issue. The St Louis MetroLink is a two-line, 38-stop light rail system that runs east to west from Lambert Airport and Shrewsbury to Scott Air Force base in Illinois. In addition to the current infrastructure, St Louis city is in the process of planning a 14-stop addition to the light rail lines that runs North-South.

This existing structure is based on specific points of interest like Busch Stadium, the Brentwood Promenade, or the Washington University Medical campus, rather than population centers or areas of high need. The figure below shows the distributions of public transit users by income and residential location (census tract), respectively. The income trend shows that roughly six times as many St Louisans earning less than 35,000 annually use the metro as any other class, while the location distribution shows that metro usage is spatially concentrated. Both trends are evidence of the immense impact stop placement can have on ridership.

The plans to install a new metro line present an opportunity to increase the overall accessibility of the entire city to individuals who rely on public transit. This study will demonstrate the use of three systems science methods to allocate new plans that are optimized on equity. The methods, k-means clustering, linear programming, and modularity maximization, will all generate an output of 14 latitude/longitude coordinate pairs that correspond to proposed stops. All plans, including the current proposed plans, will be evaluated through our own score function, ensemble analysis, and vector overlay analysis.