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• 31. [Article] Sub-regional detention siting : a methodology using GIS

  The Mt. Scott watershed in northern Clackamas County, Oregon is an urban watershed that lies inside the Portland metropolitan urban growth boundary. Urbanization of the watershed began in the early 1970s ...

  Citation × Citation Citation Abstract Copy Title: Sub-regional detention siting : a methodology using GIS Author: Murdock, Carol L. The Mt. Scott watershed in northern Clackamas County, Oregon is an urban watershed that lies inside the Portland metropolitan urban growth boundary. Urbanization of the watershed began in the early 1970s and has recently accelerated. A landscape level analysis of the urbanization process was combined with the results of a recently completed storm water master plan for the area. The project resulted in the identification of potential locations for combined detention and water quality facilities. It also served to further justify the recent revision of surface water management rules and regulations to include requirements for lower release rates from detention facilities and riparian and wetland buffers. Geographic Information Systems (GIS) was used extensively throughout the project to provide data input into the XPSWMM model that was used to analyze storm water flows and to identify infrastructure needs and requirements. In addition, GIS played a pivotal role in identifying factors which may be contributing to changes in stream condition in the basin. The results of this analysis project will be used by surface water managers in their continuing effort to refine current surface water management rules and regulations in the face of on-going development and continued urbanization. Title: Sub-regional detention siting : a methodology using GIS Author: Murdock, Carol L. The Mt. Scott watershed in northern Clackamas County, Oregon is an urban watershed that lies inside the Portland metropolitan urban growth boundary. Urbanization of the watershed began in the early 1970s and has recently accelerated. A landscape level analysis of the urbanization process was combined with the results of a recently completed storm water master plan for the area. The project resulted in the identification of potential locations for combined detention and water quality facilities. It also served to further justify the recent revision of surface water management rules and regulations to include requirements for lower release rates from detention facilities and riparian and wetland buffers. Geographic Information Systems (GIS) was used extensively throughout the project to provide data input into the XPSWMM model that was used to analyze storm water flows and to identify infrastructure needs and requirements. In addition, GIS played a pivotal role in identifying factors which may be contributing to changes in stream condition in the basin. The results of this analysis project will be used by surface water managers in their continuing effort to refine current surface water management rules and regulations in the face of on-going development and continued urbanization. Close

• 32. [Article] Geographic information systems : suitability to a land use planning problem

  Geographic Information Systems (GIS) is a burgeoning field with its roots in geography. It is increasingly being used by a large variety of disciplines, including land use planning, as a decision support ...

  Citation × Citation Citation Abstract Copy Title: Geographic information systems : suitability to a land use planning problem Author: Harmon, Robert C. Geographic Information Systems (GIS) is a burgeoning field with its roots in geography. It is increasingly being used by a large variety of disciplines, including land use planning, as a decision support tool to help solve complex spatial problems. At Oregon State University, researchers have developed an analog model which will assist planners in designating 'secondary' or marginal resource lands. The OSU Secondary Lands Model is translated into a series of digital algorithms and applied to a study area in north-central Lane County, Oregon with pcARC/INFO, a popular personal computer (PC) GIS program. Translation of the analog model to digital is analyzed and summarized in the conclusion. Lessons learned from this research are drawn upon to make recommendations to others who wish to use GIS in land use planning or any other multi-disciplinary environment. These include careful data preparation, avoiding the pitfalls of 'digital determinism,' keeping data broken down into their smallest components, and using appropiate data structures. Title: Geographic information systems : suitability to a land use planning problem Author: Harmon, Robert C. Geographic Information Systems (GIS) is a burgeoning field with its roots in geography. It is increasingly being used by a large variety of disciplines, including land use planning, as a decision support tool to help solve complex spatial problems. At Oregon State University, researchers have developed an analog model which will assist planners in designating 'secondary' or marginal resource lands. The OSU Secondary Lands Model is translated into a series of digital algorithms and applied to a study area in north-central Lane County, Oregon with pcARC/INFO, a popular personal computer (PC) GIS program. Translation of the analog model to digital is analyzed and summarized in the conclusion. Lessons learned from this research are drawn upon to make recommendations to others who wish to use GIS in land use planning or any other multi-disciplinary environment. These include careful data preparation, avoiding the pitfalls of 'digital determinism,' keeping data broken down into their smallest components, and using appropiate data structures. Close

• 33. [Article] Hierarchical Image Analysis and Characterization of Scaling Effects in Remote Sensing

  The effects of scale influence all aspects of spatial analysis and should be expressly considered early in research planning. Remotely sensed images provide unique landscape perspectives and possess several ...

  Citation × Citation Citation Abstract Copy Title: Hierarchical Image Analysis and Characterization of Scaling Effects in Remote Sensing Author: Ducey, Craig David Year: 2010 The effects of scale influence all aspects of spatial analysis and should be expressly considered early in research planning. Remotely sensed images provide unique landscape perspectives and possess several features amenable to dealing with scale. In particular, images can be segmented into image objects representative of landscape features and structured as nested hierarchies for evaluating landscape patterns across a range of scales. The objectives of this research are to evaluate methods for: 1) characterizing candidate image objects to inform the selection of user-supplied segmentation parameters and 2) exploring the multi-scale structure of landscape patterns for defining and describing potentially important scales for conducting subsequent geospatial and ecological investigations. I followed a recursive strategy to develop an image hierarchy using a corrected version of the normalized difference vegetation index (NDVIc) derived from a Landsat ETM+ satellite image over a complex, forested landscape at Lava Cast Forest (LCF), Oregon. At each scale level, I calculated an objective function based on within-object variance and spatial autocorrelation to distinguish between alternative image objects created with the region-merging segmentation algorithm available in the Definiens Developer 7 software. Segmentation quality was considered highest for results exhibiting the lowest overall within-object variance and between-object spatial autocorrelation. I then applied geographical variance analysis to calculate the independent contribution and relative variability of each level in the hierarchy to evaluate the scene's spatial structure across scales. My results reveal overall trends in image object spatial variance consistent with scaling theory, but suggest judging image object quality without sampling the entire range of segmentation parameters is insufficient. Statistical limitations of the spatial autocorrelation coefficient at small sample sizes constrained the number of possible hierarchy levels within the image spatial extent, preventing identification of larger-scale landscape patterns. Geographical variance analysis results show patterns in vegetation conditions at LCF possess a multi-scaled structure. Three levels exhibiting high variance relative to the entire hierarchy coincide with abrupt transitions in the slopes of within-object variance and spatial autocorrelation trends, which I interpreted as scale thresholds potentially important for relating landscape patterns and processes. These methods provide an objective, object-oriented approach for addressing scale issues within heterogeneous landscapes using remote sensing. Title: Hierarchical Image Analysis and Characterization of Scaling Effects in Remote Sensing Author: Ducey, Craig David Year: 2010 The effects of scale influence all aspects of spatial analysis and should be expressly considered early in research planning. Remotely sensed images provide unique landscape perspectives and possess several features amenable to dealing with scale. In particular, images can be segmented into image objects representative of landscape features and structured as nested hierarchies for evaluating landscape patterns across a range of scales. The objectives of this research are to evaluate methods for: 1) characterizing candidate image objects to inform the selection of user-supplied segmentation parameters and 2) exploring the multi-scale structure of landscape patterns for defining and describing potentially important scales for conducting subsequent geospatial and ecological investigations. I followed a recursive strategy to develop an image hierarchy using a corrected version of the normalized difference vegetation index (NDVIc) derived from a Landsat ETM+ satellite image over a complex, forested landscape at Lava Cast Forest (LCF), Oregon. At each scale level, I calculated an objective function based on within-object variance and spatial autocorrelation to distinguish between alternative image objects created with the region-merging segmentation algorithm available in the Definiens Developer 7 software. Segmentation quality was considered highest for results exhibiting the lowest overall within-object variance and between-object spatial autocorrelation. I then applied geographical variance analysis to calculate the independent contribution and relative variability of each level in the hierarchy to evaluate the scene's spatial structure across scales. My results reveal overall trends in image object spatial variance consistent with scaling theory, but suggest judging image object quality without sampling the entire range of segmentation parameters is insufficient. Statistical limitations of the spatial autocorrelation coefficient at small sample sizes constrained the number of possible hierarchy levels within the image spatial extent, preventing identification of larger-scale landscape patterns. Geographical variance analysis results show patterns in vegetation conditions at LCF possess a multi-scaled structure. Three levels exhibiting high variance relative to the entire hierarchy coincide with abrupt transitions in the slopes of within-object variance and spatial autocorrelation trends, which I interpreted as scale thresholds potentially important for relating landscape patterns and processes. These methods provide an objective, object-oriented approach for addressing scale issues within heterogeneous landscapes using remote sensing. Close

• 34. [Article] Geographic Data in City Planning Departments: The Volume and Use Related to Advancements in Geographic Information Systems (GIS) Technology

  Many local planning departments have acquired and put into use advanced automated geocoding and Geographic Information Systems (GIS) to store, process, map and analyze geographic data. GIS technological ...

  Citation × Citation Citation Abstract Copy Title: Geographic Data in City Planning Departments: The Volume and Use Related to Advancements in Geographic Information Systems (GIS) Technology Author: Kubbara, Fawzi Saeed Year: 1992 Many local planning departments have acquired and put into use advanced automated geocoding and Geographic Information Systems (GIS) to store, process, map and analyze geographic data. GIS technological advancements in hardware, software, and geographic databases - specifically, in geocoding methods to reference street address data to geographic locations - enable data to be integrated, mapped, and analyzed more efficiently and effectively. Also, technological advancements depend on organizational and institutional environments. The relationships between technological advancements and technical (data mapping and analysis), organizational, and institutional environments are not clear. The purpose of this study is to explain these relationships to help planning and development directors make better decisions in acquiring and using advanced geocoding and GIS technology. The findings are based on a mail survey of planning and development departments in cities with populations of 50,000 or more in the United States. The study found that planning departments with advanced geocoding and GIS technology are capable of conducting advanced geocoding applications. Data can be tabulated, aggregated, linked, and modeled for mapping and planning. Geocoding to aggregate data to small geographic areas helps by providing required and up-to-date information to solve urban problems. However, the study did not find that advanced geocoding systems enhance data quality as measured by spatial resolution and volume. Further studies are needed to explore this issue. The adoption and implementation of advanced geocoding and GIS technology are influenced by organizational and institutional environments. Large cities have more experience with hardware, software programs, computer professionals, and training programs, but they are dependent on centralized systems from an earlier computer era. Consequently, more recent entrants to using computers for geographic data processing are emerging rapidly. As technology is becoming more advanced, hardware and software costs are declining. Some of the organizational and institutional issues are eliminated while new ones are emerging. As a result, small area cities are adopting advanced geocoding and GIS technology more rapidly than they were previously, and sometimes they surpass large cities. This study improves understanding of automated street address geocoding methods and how these methods are related to advancements in GIS technology. The study also examines how technical, organizational, and institutional environments are interrelated in adopting and using geocoding and GIS technology. The challenge in the 1990s will not be how to fund and acquire a GIS, but how to integrate all of the pieces in order to make the technology work properly. Title: Geographic Data in City Planning Departments: The Volume and Use Related to Advancements in Geographic Information Systems (GIS) Technology Author: Kubbara, Fawzi Saeed Year: 1992 Many local planning departments have acquired and put into use advanced automated geocoding and Geographic Information Systems (GIS) to store, process, map and analyze geographic data. GIS technological advancements in hardware, software, and geographic databases - specifically, in geocoding methods to reference street address data to geographic locations - enable data to be integrated, mapped, and analyzed more efficiently and effectively. Also, technological advancements depend on organizational and institutional environments. The relationships between technological advancements and technical (data mapping and analysis), organizational, and institutional environments are not clear. The purpose of this study is to explain these relationships to help planning and development directors make better decisions in acquiring and using advanced geocoding and GIS technology. The findings are based on a mail survey of planning and development departments in cities with populations of 50,000 or more in the United States. The study found that planning departments with advanced geocoding and GIS technology are capable of conducting advanced geocoding applications. Data can be tabulated, aggregated, linked, and modeled for mapping and planning. Geocoding to aggregate data to small geographic areas helps by providing required and up-to-date information to solve urban problems. However, the study did not find that advanced geocoding systems enhance data quality as measured by spatial resolution and volume. Further studies are needed to explore this issue. The adoption and implementation of advanced geocoding and GIS technology are influenced by organizational and institutional environments. Large cities have more experience with hardware, software programs, computer professionals, and training programs, but they are dependent on centralized systems from an earlier computer era. Consequently, more recent entrants to using computers for geographic data processing are emerging rapidly. As technology is becoming more advanced, hardware and software costs are declining. Some of the organizational and institutional issues are eliminated while new ones are emerging. As a result, small area cities are adopting advanced geocoding and GIS technology more rapidly than they were previously, and sometimes they surpass large cities. This study improves understanding of automated street address geocoding methods and how these methods are related to advancements in GIS technology. The study also examines how technical, organizational, and institutional environments are interrelated in adopting and using geocoding and GIS technology. The challenge in the 1990s will not be how to fund and acquire a GIS, but how to integrate all of the pieces in order to make the technology work properly. Close

• 35. [Article] Collecting Commercial Vehicle Tour Data with Passive Global Positioning System Technology: Issues and Potential Applications

  The assessment of strategies designed to manage the continued growth in road-based freight and associated externalities has been hampered by a paucity of disaggregate data on commercial vehicle movements. ...

  Citation × Citation Citation Abstract Copy Title: Collecting Commercial Vehicle Tour Data with Passive Global Positioning System Technology: Issues and Potential Applications Author: Greaves, Stephen, Figliozzi, Miguel Year: 2008 The assessment of strategies designed to manage the continued growth in road-based freight and associated externalities has been hampered by a paucity of disaggregate data on commercial vehicle movements. When disaggregated data are available, the analysis of commercial vehicle route and trip chain structure can provide insightful information about urban commercial vehicle tours, travel patterns, and congestion levels. Over the past 15 years, the ability to collect detailed travel information has been expanded by developments in global positioning system (GPS) technology. In mid-2006, a GPS survey of commercial vehicles was piloted in Melbourne, Australia, to support a major update of freight data and modeling capabilities in the metropolitan region. The survey used passive GPS methods in which the truck driver's involvement in the data collection effort was minimal. The contributions of this research to the field of urban freight data collection were fourfold: (a) describing implementation issues with the data collection, (b) detailing the algorithms used to process the raw GPS data into meaningful travel and trip information, (c) presenting a discussion of pilot survey data tour results, and (d) discussing potential uses and limitations of GPS technology in urban freight modeling and planning. Despite processing challenges, GPS provides an appealing method to enrich commercial vehicle data collection and enhance our understanding of on-road behavior. Because increasing numbers of commercial vehicles become equipped with GPS receivers, only privacy concerns remain as a major barrier to gathering and using such data on a widespread basis in the future. Title: Collecting Commercial Vehicle Tour Data with Passive Global Positioning System Technology: Issues and Potential Applications Author: Greaves, Stephen, Figliozzi, Miguel Year: 2008 The assessment of strategies designed to manage the continued growth in road-based freight and associated externalities has been hampered by a paucity of disaggregate data on commercial vehicle movements. When disaggregated data are available, the analysis of commercial vehicle route and trip chain structure can provide insightful information about urban commercial vehicle tours, travel patterns, and congestion levels. Over the past 15 years, the ability to collect detailed travel information has been expanded by developments in global positioning system (GPS) technology. In mid-2006, a GPS survey of commercial vehicles was piloted in Melbourne, Australia, to support a major update of freight data and modeling capabilities in the metropolitan region. The survey used passive GPS methods in which the truck driver's involvement in the data collection effort was minimal. The contributions of this research to the field of urban freight data collection were fourfold: (a) describing implementation issues with the data collection, (b) detailing the algorithms used to process the raw GPS data into meaningful travel and trip information, (c) presenting a discussion of pilot survey data tour results, and (d) discussing potential uses and limitations of GPS technology in urban freight modeling and planning. Despite processing challenges, GPS provides an appealing method to enrich commercial vehicle data collection and enhance our understanding of on-road behavior. Because increasing numbers of commercial vehicles become equipped with GPS receivers, only privacy concerns remain as a major barrier to gathering and using such data on a widespread basis in the future. Close

• 36. [Article] Modeling gray wolf habitat in Oregon using a geographic information system

  Gray Wolves (Canis lupus) were once found throughout North America including Oregon. Wolves were extirpated from Oregon due to heavy hunting pressure in the late 19th and early 20th centuries and have ...

  Citation × Citation Citation Abstract Copy Title: Modeling gray wolf habitat in Oregon using a geographic information system Author: Larsen, Tad Gray Wolves (Canis lupus) were once found throughout North America including Oregon. Wolves were extirpated from Oregon due to heavy hunting pressure in the late 19th and early 20th centuries and have been absent for over 50 years. Successful reintroduction efforts in Idaho and the greater Yellowstone area have caused wolf populations in the Rocky Mountain region to rise dramatically, giving way to wolf dispersal into Oregon. This research used logistic regression and a Geographic Information System (GIS) to model and assess potential wolf habitat in Oregon. Models based on previous research were analyzed to find the best approximating wolf habitat model. These a priori models were formulated under the hypotheses that wolf habitat (1) will include relatively high densities of prey, (2) will be limited by human influence, (3) will include favorable landscape characteristics (e.g. forest cover, public ownership), and (4) may be influenced by some combination of these factors. The final model was tested and validated with wolf pack data from the Rocky Mountain region. The results show that a habitat model including variables of forest cover and public land can successfully predict wolf habitat in the study area. These results may assist natural resource managers in developing and implementing of a wolf management plan in Oregon. In addition, because the data used for the habitat model are consistent across state boundaries and are easily accessible, these results may extend to other western states. Title: Modeling gray wolf habitat in Oregon using a geographic information system Author: Larsen, Tad Gray Wolves (Canis lupus) were once found throughout North America including Oregon. Wolves were extirpated from Oregon due to heavy hunting pressure in the late 19th and early 20th centuries and have been absent for over 50 years. Successful reintroduction efforts in Idaho and the greater Yellowstone area have caused wolf populations in the Rocky Mountain region to rise dramatically, giving way to wolf dispersal into Oregon. This research used logistic regression and a Geographic Information System (GIS) to model and assess potential wolf habitat in Oregon. Models based on previous research were analyzed to find the best approximating wolf habitat model. These a priori models were formulated under the hypotheses that wolf habitat (1) will include relatively high densities of prey, (2) will be limited by human influence, (3) will include favorable landscape characteristics (e.g. forest cover, public ownership), and (4) may be influenced by some combination of these factors. The final model was tested and validated with wolf pack data from the Rocky Mountain region. The results show that a habitat model including variables of forest cover and public land can successfully predict wolf habitat in the study area. These results may assist natural resource managers in developing and implementing of a wolf management plan in Oregon. In addition, because the data used for the habitat model are consistent across state boundaries and are easily accessible, these results may extend to other western states. Close

• 37. [Article] Use of a geographical information system to modify pheromone trap-based predictions of Helicoverpa zea (Boddie) damage

  The GRASS (V. 4.0) geographical information system (GIS) was used to test the hypothesis that pheromone trap based predictions of Helicoverpa zea (Boddie) damage in processed sweet corn could be improved ...

  Citation × Citation Citation Abstract Copy Title: Use of a geographical information system to modify pheromone trap-based predictions of Helicoverpa zea (Boddie) damage Author: Drapek, Raymond James The GRASS (V. 4.0) geographical information system (GIS) was used to test the hypothesis that pheromone trap based predictions of Helicoverpa zea (Boddie) damage in processed sweet corn could be improved by considering spatial patterns of corn plantings and wind blocking features around the trap. Wind blocking features include: tree rows, wooded areas, large buildings close to the trap, and abrupt hillsides. Pheromone traps were monitored at 29 and 30 sites in 1990 and 1991. Corn development through the year and damage levels at harvest (percent infestation) were also recorded for these locations. Maps of all corn plantings and wind blocking features within 2.5 kilometers of the trap were created, digitized, and entered into the GIS for each site. A stepwise regression analysis considering 18 spatial and two non-spatial variables resulted in a highly significant (P<0.001) four variable regression model with an R² of 0.82. Spatial input variables used in this model included the total number of hectares of corn within 2.0 kilometers of the trap as well as the average distance to wind blocking features on the north side of the trap. The non-spatial variables used were cumulative trap catch and date of first silk. A dynamic simulation model was also created. This was designed to filter from the trap catch those moths coming from plantings outside of the trapped planting. This model functioned by creating map surfaces in the GIS showing for each day the relative contribution to catch for each location around the trap. This map surface was the product for each location of relative moth population levels and the likeliness that a moth positioned there would be captured by the trap. The modified cumulative trap catch was expected to correlate more strongly to damage levels than the unmodified trap catch, but no run of the model produced a significant improvement in the correlation. In the process of collecting data for this project, circumstantial evidence was obtained which indicated that high synchrony between valley-wide moth catch levels and valley-wide timings of silking in corn could be used as an indicator of high damage years. Title: Use of a geographical information system to modify pheromone trap-based predictions of Helicoverpa zea (Boddie) damage Author: Drapek, Raymond James The GRASS (V. 4.0) geographical information system (GIS) was used to test the hypothesis that pheromone trap based predictions of Helicoverpa zea (Boddie) damage in processed sweet corn could be improved by considering spatial patterns of corn plantings and wind blocking features around the trap. Wind blocking features include: tree rows, wooded areas, large buildings close to the trap, and abrupt hillsides. Pheromone traps were monitored at 29 and 30 sites in 1990 and 1991. Corn development through the year and damage levels at harvest (percent infestation) were also recorded for these locations. Maps of all corn plantings and wind blocking features within 2.5 kilometers of the trap were created, digitized, and entered into the GIS for each site. A stepwise regression analysis considering 18 spatial and two non-spatial variables resulted in a highly significant (P<0.001) four variable regression model with an R² of 0.82. Spatial input variables used in this model included the total number of hectares of corn within 2.0 kilometers of the trap as well as the average distance to wind blocking features on the north side of the trap. The non-spatial variables used were cumulative trap catch and date of first silk. A dynamic simulation model was also created. This was designed to filter from the trap catch those moths coming from plantings outside of the trapped planting. This model functioned by creating map surfaces in the GIS showing for each day the relative contribution to catch for each location around the trap. This map surface was the product for each location of relative moth population levels and the likeliness that a moth positioned there would be captured by the trap. The modified cumulative trap catch was expected to correlate more strongly to damage levels than the unmodified trap catch, but no run of the model produced a significant improvement in the correlation. In the process of collecting data for this project, circumstantial evidence was obtained which indicated that high synchrony between valley-wide moth catch levels and valley-wide timings of silking in corn could be used as an indicator of high damage years. Close

• 38. [Article] Measuring Food Deserts: A Comparison of Models Measuring the Spatial Accessibility of Supermarkets in Portland, Oregon

  xiii, 75 p. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.

  Citation × Citation Citation Abstract Copy Title: Measuring Food Deserts: A Comparison of Models Measuring the Spatial Accessibility of Supermarkets in Portland, Oregon Author: Sparks, Andrea Year: 2008 xiii, 75 p. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Title: Measuring Food Deserts: A Comparison of Models Measuring the Spatial Accessibility of Supermarkets in Portland, Oregon Author: Sparks, Andrea Year: 2008 xiii, 75 p. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Close

• 39. [Article] Assessing Transit Fare Equity in Utah Using a Geographic Information System

  The goal of this study is to develop and apply a new method for assessing social equity impacts of distance-based public transit fares. Shifting to a distance-based fare structure can disproportionately ...

  Citation × Citation Citation Abstract Copy Title: Assessing Transit Fare Equity in Utah Using a Geographic Information System Author: Farber, Steven, Batholomew, Keith, Li, Xiao, Paez, Antonio, Nurul Habib, Khandker M. Year: 2014 The goal of this study is to develop and apply a new method for assessing social equity impacts of distance-based public transit fares. Shifting to a distance-based fare structure can disproportionately favor or penalize different subgroups of a population based on variations in settlement patterns, travel needs, and most importantly, transit use. According to federal law, such disparities must be evaluated by the transit agency, but the area-based techniques identified by the Federal Transit Authority for assessing discrimination fail to account for disparities in distances travelled by transit users. This means that transit agencies currently lack guidelines for assessing the social equity impacts of replacing flat fare with distance-based fare structures. Our solution is to incorporate a joint ordinal-continuous model of trip generation and distance travelled into a GIS Decision Support System. The system enables a transit planner to visualize and compare estimated distances travelled and transit-cost maps for different population profiles and fare structures. We apply the method to a case study in the Wasatch Front, Utah, where the Utah Transit Authority is exploring a switch to a distance-based fare structure. The analysis reveals that overall distance-based fares benefit low-income, elderly, and non-white populations. However, the effect is geographically uneven, and may be negative for members of these groups living on the urban fringe. The research discusses a potential conflict between policies designed to promote equity and those intended to increase discretionary ridership. For example, increasing fares for longdistance discretionary riders travelling from suburban light-rail stations to the central business district may have a negative impact on ridership, despite being economically more efficient through cost-recapturing. At the same time, reducing fares for short-distance trips that are currently too expensive compared to private automobile travel may attract new riders. A full cost-benefit analysis sensitive to heterogeneous price elasticity is recommended for future research. It is also noted that the research findings are dependent on the current spatial distributions of population segments and travel patterns. The equity benefits of distance-based fares are primarily derived from residential clustering of low-income and minority groups in more compact urban areas near the center of the city. Demographic trends, such as inner-city gentrification and suburban aging-in-place, may impose increased travel demands on low income and elderly riders, nullifying future equity gains made by a transition to distance-based fares. Title: Assessing Transit Fare Equity in Utah Using a Geographic Information System Author: Farber, Steven, Batholomew, Keith, Li, Xiao, Paez, Antonio, Nurul Habib, Khandker M. Year: 2014 The goal of this study is to develop and apply a new method for assessing social equity impacts of distance-based public transit fares. Shifting to a distance-based fare structure can disproportionately favor or penalize different subgroups of a population based on variations in settlement patterns, travel needs, and most importantly, transit use. According to federal law, such disparities must be evaluated by the transit agency, but the area-based techniques identified by the Federal Transit Authority for assessing discrimination fail to account for disparities in distances travelled by transit users. This means that transit agencies currently lack guidelines for assessing the social equity impacts of replacing flat fare with distance-based fare structures. Our solution is to incorporate a joint ordinal-continuous model of trip generation and distance travelled into a GIS Decision Support System. The system enables a transit planner to visualize and compare estimated distances travelled and transit-cost maps for different population profiles and fare structures. We apply the method to a case study in the Wasatch Front, Utah, where the Utah Transit Authority is exploring a switch to a distance-based fare structure. The analysis reveals that overall distance-based fares benefit low-income, elderly, and non-white populations. However, the effect is geographically uneven, and may be negative for members of these groups living on the urban fringe. The research discusses a potential conflict between policies designed to promote equity and those intended to increase discretionary ridership. For example, increasing fares for longdistance discretionary riders travelling from suburban light-rail stations to the central business district may have a negative impact on ridership, despite being economically more efficient through cost-recapturing. At the same time, reducing fares for short-distance trips that are currently too expensive compared to private automobile travel may attract new riders. A full cost-benefit analysis sensitive to heterogeneous price elasticity is recommended for future research. It is also noted that the research findings are dependent on the current spatial distributions of population segments and travel patterns. The equity benefits of distance-based fares are primarily derived from residential clustering of low-income and minority groups in more compact urban areas near the center of the city. Demographic trends, such as inner-city gentrification and suburban aging-in-place, may impose increased travel demands on low income and elderly riders, nullifying future equity gains made by a transition to distance-based fares. Close