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Pages 77-102

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From page 77... ... Since daily and weekly activity schedules vary widely by socioeconomic variables such as class, life cycle, culture, and gender roles, space-time accessibility measures are sensitive to individual differences in accessibility. Spacetime accessibility measures can support livability measures that take into account the varying access to resources and opportunities between social and demographic groups in a community. Read the entire page →
From page 81... ... MEASUREMENT AND ANALYSIS OF LIVABILITY 81 DEVELOPING PLACE-BASED INDICATORS Most place-based analyses use data reported at an aggregate level for some kind of geographic area. Examples include census tracts, census block groups, traffic assignment zones, school districts, or political units such as municipalities and counties. Read the entire page →
From page 82... ... For example, as spatial units become more elongated, point pattern statistics tend to report higher levels of clustering for the same point pattern within that unit (Fotheringham and Rogerson, 1993~. Shape relative to area can also affect the measurement of interactions (e.g., origin-destination flows) Read the entire page →
From page 83... ... Data for livability indicators are often spatially aggregated according to a defined spatial zoning system such as census tracts, census block groups, school districts, or political units such as municipalities or counties. These units can be meaningful in reality; for example, municipalities correspond Read the entire page →
From page 84... ... Problems associated with arbitrary geographic units are known as the modifiable areal unit problem (MAUP) in the spatial analysis and quantitative geography literatures. Read the entire page →
From page 85... ... This grouping creates even more dramatic change in apparent livability: 11 of the 13 towns have different classifications relative to those in Figure 3.3. Town 16 LIVABILITY LOW MEDIUM HIGH FIGURE 3.3 Hypothetical livability index mapped for the 16 towns. Read the entire page →
From page 86... ... 86 COMMUNITY AND QUALITY OF LIFE LIVABILITY I I LOW MEDIUM HIGH FIGURE 3.4 Hypothetical livability index mapped for a north-south aggregation. LIVABILITY I I LOW MEDIUM HIGH FIGURE 3.5 Hypothetical livability index mapped for an east-west aggregation. Read the entire page →
From page 87... ... We can create substantially different patterns of livability At_ :\ ,~ FIGURE 3.6 Hypothetical livability index mapped for a metropolitannonmetropolitan aggregation. Read the entire page →
From page 88... ... What can be done about the modifiable areal unit problem when measuring and analyzing livability? One strategy is to attempt to develop optimal spatial units for the particular problem being addressed. Read the entire page →
From page 89... ... A place-based strategy is to aggregate the space-time paths into spacetime units using temporal measurements taken at discrete time intervals for the spatial reporting units (Taylor and Parkes, 1975~. Examples of space-time units are census block groups with attributes measured at different representative times such as "weekday morning," "weekday evening," "weekend morning," and "weekend evening." In contrast, the standard census practice of recording attributes based on home location assumes a particular time (e.g., weekday evening) Read the entire page →
From page 90... ... If both the source and the target zones are relatively homogeneous, the method of areal weighting can be used. This method distributes the data in the source zones to the target zones based on the share of the source zone within each target zone (see Goodchild and Lam, 1980~. Read the entire page →
From page 91... ... Spatial-Temporal Data and Inferential Statistics The connectedness of livability in space and time is concerned with two other issues related to inferential statistics: namely, spatial dependence and spatial heterogeneity. We often refer to spatial dependence as spatial autocorrelation when discussing this property from a statistical perspective. Read the entire page →
From page 92... ... Problems associated with spatial dependence among observations in multivariate regression and related techniques can be resolved by including spatial autocorrelation in the dependent variable, independent variables, error terms, or some combination (Anselin, 1988, 1993~. Spatial dependence and spatial heterogeneity can tee captured simultaneously using geographically weighted regression. Read the entire page →
From page 93... ... Accessibility measures should be sensitive to the widely varying needs and resources of different social and demographic groups. The daily, weekly, and monthly activity schedules of individuals vary substantially by socioeconomic class, life cycle, culture, and gender roles (see Golledge and Stimson, 1997~. Read the entire page →
From page 94... ... . The projection of the prism to the twodimensional plane provides the potential path area (i.e., all locations in geographic space that the person can occupy during that discretionary period) Read the entire page →
From page 95... ... Space-time accessibility measures derived from time geography highlight the role of transportation technology in trading time for space but do not incorporate the role that communication and information technologies play in eliminating space for certain activities. Yet, even as these technologies permit more activities and information exchange in cyberspace, persistent inequalities in access to information technologies (often called the digital gap or divide) Read the entire page →
From page 96... ... Digital geographic data and GIS tools should be used to conduct sensitivity analyses of livability indicators with respect to changes in aggregation and zoning. Computational methods can also be used to form optimal spatial units for some measures. Read the entire page →
From page 97... ... Including space-time constraints in accessibility measures captures the influence of individuals' activity schedules and major anchor points on their access to resources, opportunities, and activities. These schedules vary substantially by social class, cultural, life cycle, and gender roles. Read the entire page →
From page 98... ... An evaluation of correction techniques for boundary effects in spatial statistical analysis: Traditional methods. Geographical Analysis 15:352-360. Read the entire page →
From page 99... ... . Geographical Analysis 31:373-399. Read the entire page →
From page 100... ... 1997. Analysis of time-space activity patterns in tourist recreation complexes: A GIS-oriented methodology. Read the entire page →
From page 102... ... National Capital, Traffic Circle, 1942, by Gluyas Williams. Courtesy of New Yorker magazine. Read the entire page →

From page 77...

... Since daily and weekly activity schedules vary widely by socioeconomic variables such as class, life cycle, culture, and gender roles, space-time accessibility measures are sensitive to individual differences in accessibility. Spacetime accessibility measures can support livability measures that take into account the varying access to resources and opportunities between social and demographic groups in a community.