A Measurement Theory for Time Geography

Abstract

Hägerstrand's time geography is a powerful conceptual framework for understanding constraints on human activity participation in space and time. However, rigorous, analytical definitions of basic time geography entities and relationships do not exist. This limits abilities to make statements about error and uncertainty in time geographic measurement and analysis. It also compromises comparison among different time geographic analyses and the development of standard time geographic computational tools. The time geographic measurement theory in this article consists of analytical formulations for basic time geography entities and relations, specifically, the spacetime path, prism, composite path-prisms, stations, bundling, and intersections. The definitions have arbitrary spatial and temporal resolutions and are explicit with respect to informational assumptions: there are clear distinctions between measured and inferred components of each entity or relation. They are also general to n-dimensional space rather than the strict two-dimensional space of classical time geography. Algebraic solutions are available for one or two spatial dimensions, while numeric (but tractable) solutions are required for some entities and relations in higher dimensional space.

El uso del tiempo en espacios próximos. Una caracterización de la ciudad de Barcelona (2006)

“…La pregunta que entonces le surgió fue si los esfuerzos para dar realismo espacial y generalidad a los aspectos económicos se habían reflejado también en un realismo humano y generalidad a aspectos de organización espacial. La respuesta a esta pregunta era difícil de encontrar en esa época, así como señalaban lsard y Reiner en 1966, "los modelos sobre el comportamiento humano en el espacio han 6 Citado en : Miller, 2005. ciudad es 17 (2014) Dossier Monográfico estado principalmente orientados a la conducta probabilística de las masas" (Miller, 2005).…”

“…3. Trayecto espacio-temporal individual (Miller, 2005). La novedad del enfoque planteado es que permite reflejar de una forma más real el comportamiento tanto de los tiempos como de los espacios utilizados en la ciudad.…”

The relationship between opening hours and accessibility of public service delivery

“…Each ܵܶ is constrained by the compulsory trip from loc൫‫ݔ‬ ൯ at ݁ to loc൫‫ݔ‬ ାଵ ൯ at ‫ݏ‬ ାଵ . In line with time geography, we will refer to this space-time volume ܵܶ as the space-time prism (Miller, 2005).…”

A GIS toolkit for measuring and mapping space–time accessibility from a place-based perspective

“…2 and Fig. 3 -a STP is obtained from the intersection of a cone oriented forward in time and a cone oriented backward in time (Miller 2005). These cones respectively represent the condition that all parts of the STP should be reachable from the origin within the time budget and that the destination should be reachable within the time budget from each point of the STP.…”