Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A global take on congestion in urban areas   We analyze the congestion data collected by a GPS device company (TomTom) for
almost 300 urban areas in the world. Using simple scaling arguments and data
fitting we show that congestion during peak hours in large cities grows
essentially as the square root of the population density. This result, at odds
with previous publications showing that gasoline consumption decreases with
density, confirms that density is indeed an important determinant of
congestion, but also that we need urgently a better theoretical understanding
of this phenomena. This incomplete view at the urban level leads thus to the
idea that thinking about density by itself could be very misleading in
congestion studies, and that it is probably more useful to focus on the spatial
redistribution of activities and residences.

18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
17
The categories of this paper are: q-fin
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
26
The categories of this paper are: bayes-an
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an