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Cake day: June 11th, 2023

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  • zaphod@feddit.detoData Is Beautiful@lemmy.ml*Permanently Deleted*
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    1 year ago

    Weird selection of cities. Very U.S. centric considering they claim “geographical diversity”.

    To better understand urban spatial order and city street network entropy, we analyze 100 large cities across North America, South America, Europe, Africa, Asia, and Oceania. Our sampling strategy emulates Louf and Barthelemy’s (2014) to select cities through a balance of high population, regional significance, and some stratification to ensure geographical diversity within regions.


  • Just read the study? They modelled street networks as undirected graphs, one-way streets are treated like all other streets, as their directionality isn’t considered.

    Street networks are typically modeled as graphs where nodes represent intersections and dead-ends, and edges represent the street segments that link them (Barthelemy and Flammini 2008; Cardillo et al. 2006; Lin and Ban 2013; Marshall et al. 2018; Porta et al. 2006). These edges are spatially embedded and have both a length and a compass bearing (Barthelemy 2011). The present study models urban street networks as undirected nonplanar multigraphs with possible self-loops. While directed graphs most-faithfully represent constraints on flows (such as vehicular traffic on a one-way street), undirected graphs better model urban form by corresponding 1:1 with street segments (i.e., the linear sides of city blocks). While many street networks are approximately planar (having relatively few overpasses or underpasses), nonplanar graphs provide more accurate models by accommodating those bridges and tunnels that do often exist (Boeing 2018c; Eppstein and Goodrich 2008).