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Going Nowhere Fast? . Roy Samaan 14 March 2011 UP 206 A. Effects of Service Reduction on Transit Quality . Roadmap. Research Basis Review of Previous Conclusions Examination of New Variables Use of New Variables to Construct Transit Quality Index Summary of Findings Conclusion
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Going Nowhere Fast? Roy Samaan 14 March 2011 UP 206 A • Effects of Service Reduction on Transit Quality
Roadmap • Research Basis • Review of Previous Conclusions • Examination of New Variables • Use of New Variables to Construct Transit Quality Index • Summary of Findings • Conclusion • Need for Refinement • Questions
Central Policy Questions • Does the elimination of METRO bus lines significantly degrade access to transit? • How is quality of transit in most transit dependent tracts affected? • Are there existing alternatives to eliminated service?
DEC 2010: Access Maintained, Quality Reduced • Only East/West Rapid Buses connecting SE LA & SW LA are eliminated & replaced with local service • Rapids connected high poverty areas with transit hubs & job centers
No Additional East/West Rapids Within 1mile of Cancelled Rapid Lines • Standard walk distance is ¼ mile • Cancelled North/South Rapids are within1 mile of existing Rapid service
Cancelled Rapid Lines Are in High Usage Corridors • Transit usage in study area high among those earning less than $65k • Indicates strong preference for public transit, if not outright transit dependency
Poverty is Useful For Predicting Need, Not Quality of Service • Quality of Service based on multiple factors: • Congestion, transit dependency factors, and speed of rapid bus relative to local bus contribute to service quality • Combining indexed Need Factors and Congestion Factors Gives a rough estimate of service quality
Generation of Need Index • Need Index = (% Poverty in tract + % under 18 + % 65 and up + Usage Intensity) • Weighted towards toward FTA-defined transit dependency variables • Intensity of use given slightly more weight than other factors
Comparison of Need Score vs. Poverty • Highest need scores do not correlate directly to highest poverty • Cancelled rapid lines covered need areas not currently covered by existing rapid service
Calculation of Congestion Index • Factors examined include: • Existing bus stop density, local line density, rapid line density, roadway density and took into account rapid line speed relative to local line speed • Densities were calculated using the following formula: • Attribute Density = (Attribute/Area)*(Population/Area) => [Attribute *population/(Area*Area)] • Spatial joins, field calculator and field geometry used to generate data • Stop density and road density weighted least; rapid density highest
How does Congestion Score Correlated to Poverty? • High poverty tracts around cancelled east/west lines are only moderately congested relative to DTLA & SFV
Combining Need Index and Congestion Index • Very few High Need areas also had high congestion • However, the higher the poverty rate, the higher the average index scores
Creating Transit Quality Index • Need Index scores were weighted slightly higher than Congestion Index scores • Calculated TQI for each census tract • It looks like this….
Countywide Transit Quality Scores • Cancelled rapid lines were an efficient way to get from one low transit quality area to another
Summary of Findings • Does the elimination of METRO bus lines significantly degrade access to transit? No. • How is quality of transit in most transit dependent tracts affected? Negatively. • Are there existing alternatives to eliminated service? Yes for north/south Rapid lines; No for east/west Rapid lines
Conclusions • Cancelled rapid lines, especially east/west lines, served high poverty riders • These lines served census tracts with high need scores and with lower congestion costs than other parts of the city • The loss of these lines reduces the transit quality in southeast and southwest Los Angeles
Necessary Refinement • Both Need and Congestion Indices only give rough estimates • Correlating high index scores with demographic data beyond poverty rates • Analysis of forthcoming and proposed (30/10) rail lines