UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Visualising space-time dynamics in scaling systems

Batty, M.; (2010) Visualising space-time dynamics in scaling systems. (CASA Working Papers 152). Centre for Advanced Spatial Analysis (UCL): London, UK. Green open access

[thumbnail of 19246.pdf] PDF
19246.pdf

Download (1MB)

Abstract

The signature of scaling in human systems is the well-known power law whose key characteristic is that the size distributions of the elements or objects that comprise such systems, display self-similarity in space and time. In fact, in many of the systems such as cities, firms, and high buildings which we use as examples, power laws represent an approximation to the fat or heavy tails of their rank-size distributions, appearing to be stable in time showing little sign of changes in their scaling over tens or even hundreds of years. However when we examine the detailed dynamics of how their ranks shift in time, there is considerable volatility with the objects in such distributions not often persisting for longer than about 50-100 years. To explore this kind of micro-volatility, we introduce a number of measures of rank shift over space and time and visualise size distributions using the idea of the ‘rank clock’. We use the example of changes in the populations of Italian towns between 1300 and 1861 to introduce these ideas and then compare this analysis with city-size distributions for the World from 430BCE, the US from 1790, the UK from 1901, and Israel from 1950. The morphologies of growth and change displayed by these clocks are all quite different. When we compare these to the distribution of US firms from 1955 in the Fortune 500 and to the distribution of high buildings in New York City and the World from 1909, we generate a panoply of different visual morphologies and statistics. This provides us with a rich portfolio of space-time dynamics that adds to our understanding of how different systems can display stability and regularity at the macro level with a very different dynamics at the micro.

Type: Working / discussion paper
Title: Visualising space-time dynamics in scaling systems
Open access status: An open access version is available from UCL Discovery
Publisher version: http://www.casa.ucl.ac.uk/publications/workingPape...
Language: English
UCL classification: UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of the Built Environment > Centre for Advanced Spatial Analysis
URI: https://discovery.ucl.ac.uk/id/eprint/19246
Downloads since deposit
333Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item