The most influential contribution to the discussion about the relation between the urban fabric and the generation of diversity, was put forth fifty years ago by Jane Jacobs (Jacobs 1961). More specifically, she pointed out four major criteria that, according to her, were necessary for the development of diverse urban public spaces: small blocks, mix of primary uses, aged buildings and concentration of people. All these variables have since then been ubiquitous in debates on urban planning and design and have also been applied in design of concrete projects. At the same time, it is quite obvious how they all are quite vague and lack rigorous definitions, why, even though they have become popular truths, we know very little about their actual effects.
In this paper we therefore redefine Jacobs' criteria in the analytically more rigorous concepts and measures developed in space syntax research and its extensions. We interpret Jacobs’ criterion ‘small blocks’ into measures of relative distance in the street network more particularly the measurements integration and choice, applied at different radii, argued to represent analysis at different scales. The criterion ‘concentration of people’ is interpreted as urban density. More precisely, this is measured using attraction accessibility analysis of night and day populations developed in the Place Syntax Tool (Ståhle, Marcus, and Karlström 2005), once again at different radii. ‘Mix of primary functions’ is partly covered by analysis of day and night populations but here we have also added accessibility to commercial activities, furthermore, an important difference is that we focus, the degree of mix and balance between these activities and not only their size. The final criterion ‘aged buildings’ is analysed as degree of land-division into discreet plots and parcels, which in earlier studies has proven to correlate well with diversity in urban uses (Marcus 2010).
These measures are applied in an extensive empirical investigation of retail distribution in Stockholm comparing the intensity (amount of shops) and diversity (variation of shops) in both local suburban centres and between the inner city and the outer city, as a substantial test of Jacobs’ criteria in this form of space syntax interpretation. The results in general clearly support Jacobs’ argument but also give rise to further discussion. In extension, this study also contributes empirical support to the principally vital question, not least for space syntax research, about how spatial form not only play an important part in generating variations in size of co-presence throughout urban space, but also how it is part in generating variations of the constitution of co-presence, that is, the diversity of co-presence.
Sejong Unviersity Press , 2013.