Net product entry is procyclical, which amplifies fluctuations in consumer welfare over the cycle if consumers have love for variety. Using barcode-level data covering grocery expenditures in 26 major cities, I establish that differences in city-level product entry are largely uncorrelated with local economic conditions. I provide evidence that city-level changes in product variety over the bus...

With urban population increasing dramatically worldwide, cities are playing an increasingly critical role in human societies and the sustainability of the planet. An obstacle to effective policy is the lack of meaningful urban metrics based on a quantitative understanding of cities. Typically, linear per capita indicators are used to characterize and rank cities. However, these implicitly ignor...

2205 This paper builds on a recently proposed algorithm to construct cities based on geographical features of high-quality micro data (Hernán D. Rozenfeld et al. 2008), rather than informative but somewhat arbitrary legal or administrative definitions. It allows us to take a fresh look at key quantities in urban economics, namely the population and the area of cities. We find that Zipf’s law fo...

Helping cities to function more effectively and efficiently is one of the best ways to achieve global sustainability goals. Such improvements can come from new technologies, new information, or new management practices. This paper focuses on ways that cities can benefit from collaborations involving nonmunicipal levels of government, private companies, nongovernmental organizations, and univers...

abstract the faunistic study was carried out during 2002-2003 and specimens were collected from 13 cities of the west azarbaijan province showing a normal distribution of this family. totally 22 genera and 35 species of pentatominae and podopinae subfamilies were collected and identified mainly focusing on male genitalia and some other morphological characters. 30 new species and 1 new species ...

during the safavid rule, due to the close relationship between the government and the structure of religious institution, the economic life of many religious leaders was based on the bureaucratic salaries and aids granted by the government. however, after the fall of safavids and transfer of the shia scientific and juridico-religious centres (i.e. seminaries) from iran to the holy cities of ira...