Robert B Noland | Rutgers, The State University of New Jersey (original) (raw)
Papers by Robert B Noland
Transportation Research Board 88th Annual MeetingTransportation Research Board, 2009
The majority of evidence on gasoline demand elasticities is derived from models based on national... more The majority of evidence on gasoline demand elasticities is derived from models based on national data. Since the largest growth in population is now taking place in cities in the developing world it is important that we understand whether this national evidence is applicable to demand conditions at the local level. The aim of this paper is to estimate and compare gasoline per vehicle demand elasticities at the national and local levels in Mexico. National elasticities with respect to price, income, vehicle stock and metro fares are estimated using both a time series cointegration model and a panel GMM model for Mexican states. Estimates for Mexico City are derived by modifying national estimates according to mode shares as suggested by Graham and Glaister (2006), and by estimating a panel Within Groups model with data aggregated by borough. Although all models agree on the sign of the elasticities the magnitudes differ greatly. Elasticities change over time and differ between the national and local levels, with smaller price responses in Mexico City. In general, price elasticities are smaller than those reported in the gasoline demand surveys, a pattern previously found in developing countries. The fact that income and vehicle stock elasticities increase over time may suggest that vehicles are being used more intensively in recent years and that Mexico City residents are purchasing larger vehicles. Elasticities with respect to metro fares are negligible, which suggests little substitution between modes. Finally, the fact that fuel efficiency elasticities are smaller than vehicle stock elasticities suggests that vehicle stock size, rather than its composition, has a larger impact on gasoline consumption in Mexico City.
International Journal of Sustainable Transportation, 2011
ABSTRACT
Transport Policy, 2009
Time series cointegration techniques are used to estimate whether the Mexico City metro is percei... more Time series cointegration techniques are used to estimate whether the Mexico City metro is perceived as a normal or inferior good. Owing to the fact that the Mexico City metro mainly serves the low income sectors of the population, this paper attempts to separate the overall income effect into two uncorrelated components: a vehicle stock effect (used as a proxy for medium/high income) and minimum wage effect net of the influence of vehicle stock (used as a proxy for low income). The time series cointegration results show that minimum wage elasticities are positive whilst vehicle stock elasticities are negative. These results suggest that for the majority of metro users, whose salaries are based on low multiples of the minimum wage and are not potential car owners, the Mexico City metro is perceived as a normal good. However, for middle/high income earners, who can afford to buy a private vehicle when their incomes increase, the Mexico City metro is perceived as an inferior good.
Journal of Navigation, May 1, 2003
This paper describes the features of an extended Kalman filter algorithm designed to support the ... more This paper describes the features of an extended Kalman filter algorithm designed to support the navigational function of a real-time vehicle performance and emissions monitoring system currently under development. The Kalman filter is used to process global positioning system (GPS) data enhanced with dead reckoning in an integrated mode, to provide continuous positioning in built-up areas. The dynamic model and filter algorithms are discussed in detail, followed by the findings based on computer simulations as well as a limited field trial carried out in the Greater London area. The results of using the extended Kalman filter algorithm demonstrate that the integrated system employing GPS and low cost dead reckoning devices is capable of meeting the required navigation performance of the device under development.
Transportation Research Board 88th Annual MeetingTransportation Research Board, 2009
There is extensive research estimating the productivity gains from agglomeration economies, but t... more There is extensive research estimating the productivity gains from agglomeration economies, but there is a paucity of evidence on the spatial scale over which such benefits are available to firms and how they decay with distance. We show how commuting gravity-type models can be used to estimate the spatial decay of the benefits of agglomeration economies arising from labour pooling forces and perform estimation of such models using data on work trips for UK travel-to-work areas. Our findings show that the distance-decay parameter is smaller than the value commonly assumed in the empirical literature. This result suggests that the existing evidence could be underestimating the spatial scale of agglomeration externalities. In addition, we find that the size of the spatial decay gradient varies across employment areas. To investigate the variation of the distance-decay estimates we carry out a further piece of analysis by estimating a regression of the spatial decay estimates on a set of regressors thought to influence the value of the decay parameter. The results suggest that smaller distance-decay gradients are associated with more unbalanced spatial distribution of the resident population and employment, whereas it will be larger for employment areas with more diversified economic structures. On the other hand, we fail to find any significant contribution of access to transport infrastructure and attribute part of the explanation of this result to the limited ability of the measures to proxy for actual accessibility to economic activities.
Journal of Navigation, Apr 18, 2005
Map Matching (MM) algorithms are usually employed for a range of transport telematics application... more Map Matching (MM) algorithms are usually employed for a range of transport telematics applications to correctly identify the physical location of a vehicle traveling on a road network. Examples of such applications are in-car navigation systems, dynamic route guidance, fleet management, incident management, public transport management and real-time highway information provision. Two essential components for MM algorithms are (1) navigation sensors such as the Global Positioning System (GPS) and dead reckoning (DR), among others, to estimate the position of the vehicle, and (2) a digital base map for spatial referencing of the vehicle location. Previous research by the authors (Quddus et al., 2003; Ochieng et al., 2003) has developed improved MM algorithms that take account of the vehicle speed and the error sources associated with the navigation sensors and the digital map data previously ignored in conventional MM approaches. However, no validation study assessing the performance of MM algorithms has been presented in the literature. This paper describes a generic validation strategy and results for the MM algorithm previously developed in Ochieng et al (2003). The validation technique is based on a higher accuracy reference (truth) of the vehicle trajectory as determined by high precision positioning achieved by the carrierphase observable from GPS. The results show that the vehicle positions determined from the MM results are within 6m of the truth positions. The results also demonstrated the importance of the quality of the digital map data to the map matching process.
Transportation Research Record, 2004
This paper presents an analyses of pedestrian and bicycle casualties using cross-sectional time-s... more This paper presents an analyses of pedestrian and bicycle casualties using cross-sectional time-series data for the regions of Great Britain. A fixed effect negative binomial model is used which accounts for heterogeneity in the data and the distributional properties of count data. Various factors associated with those killed and seriously injured as well as slight injuries are examined. These include the average age of vehicles in the region, the road length of various road classes, the amount of vehicle ownership in the region, per capita income, per capita expenditure on alcohol, age cohorts, and various proxies for medical technology improvements. Various specifications of the models are estimated. Generally, we find that more serious pedestrian injuries are associated with lower income areas, increases in percent of local roads, increased per capita expenditure on alcohol, and total population. Statistical effects are harder to detect in models with serious injuries for bicyclists, but alcohol expenditure is strongly associated with increased injuries. This work has implications for transport policy aimed at increasing the modal share of pedestrians and bicyclists. Further research is needed to clearly understand some of the trends found in our analyses, especially the effect of changes in medical care and technology on total injuries.
Proceedings of the 17th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS 2004), Sep 24, 2004
... Y., Quddus, Mohammed A., Noland, Robert B., "Integrated Positioning Algorithms for T... more ... Y., Quddus, Mohammed A., Noland, Robert B., "Integrated Positioning Algorithms for Transport Telematics Applications," Proceedings of the 17th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS 2004), Long Beach, CA ...
Journal of Safety Research, Dec 1, 2002
Papers in Regional Science, Jun 1, 2009
Transportation Research Board 87th Annual MeetingTransportation Research Board, 2008
This paper investigates the relationship between firm formation and the availability of motorway ... more This paper investigates the relationship between firm formation and the availability of motorway and railway networks using data on Portuguese firm births for the periods 1995 and 2003. It develops an econometric model using micro level data in a geographic information system (GIS) to examine whether transport infrastructure has an impact on firm birth, to show how such impacts vary across industrial sectors, and to determine the relative magnitude of effects arising from rail and motorway networks. We conclude that the most significant factors influencing new firm birth are supply side variables and industrial economic structure. Labour costs and small firm size are strong significant locational determinants of firm births. Improvements in the railway and motorway networks do not appear to have a significant effect on new firm formation.
Transportation Research Board 89th Annual MeetingTransportation Research Board, 2010
This paper presents a model based on traffic count data to evaluate the potential effects of dist... more This paper presents a model based on traffic count data to evaluate the potential effects of distance-based road user charges in the Mexico City Metropolitan Area. The impact of marginal social cost pricing and environmental charges is assessed for both revenue raising and revenue neutral scenarios. Four user responses are allowed in the model: changes in vehicle occupancy, time switching, mode shift, and trip suppression. The model forecasts changes in traffic flows, speeds, public transport patronage and government revenue, for different area types and different times of the day. The results suggest that marginal social cost pricing would reduce traffic by about 14 percent and the revenues from the scheme would be equivalent to about 50 percent of the total Mexico City budget.
RePEc: Research Papers in Economics, Aug 1, 2003
A disaggregate spatial analysis, using enumeration district data for London was conducted with th... more A disaggregate spatial analysis, using enumeration district data for London was conducted with the aim of examining how congestion may affect traffic safety. It has been hypothesized that while congested traffic conditions may increase the number of vehicle crashes and interactions, their severity is normally lower than crashes under uncongested free flowing conditions. This is primarily due to the slower speeds of vehicles when congestion is present. Our analysis uses negative binomial count models to examine whether factors affecting casualties (fatalities, serious injuries and slight injuries) differed during congested time periods as opposed to uncongested time periods. We also controlled for congestion spatially using a number of proxy variables and estimated pedestrian casualty models since a large proportion of London casualties are pedestrians. Results are not conclusive. Our results suggest that road infrastructure effects may interact with congestion levels such that in London any spatial differences are largely mitigated. Some small differences are seen between the models for congested versus uncongested time periods, but no conclusive trends can be found. Our results lead us to suspect that congestion as a mitigator of crash severity is less likely to occur in urban conditions, but may still be a factor on higher speed roads and motorways.
A technically and economically feasible road user charging scheme should be based on quantities t... more A technically and economically feasible road user charging scheme should be based on quantities that are readily and accurately measurable, as well as being directly variable with the amount of road use and its impact on the environment and society. A key requirement for a pricing scheme is that the charging regime used should be easy for motorists to understand, but at the same time flexible enough for the operator to implement a wide range of policies to meet different aims. A set of variable road user charging indicators is identified herein by considering both the associated costs of a trip and the operational requirements for a feasible road pricing scheme. The study then focused on identifying a set of currently feasible technologies to measure these variables in real-time with high accuracy. Particular attention was paid to the need accurately to track vehicle movements and link these movements to geographical areas and road types, and the key pollutants and particulate matter, all of which have different potential effects that are in some cases dependent on location and time of emissions. Other issues, such as congestion measurement, are also discussed. (A)
RePEc: Research Papers in Economics, Aug 1, 2002
Great Britain has one of the lowest levels of traffic-related fatalities in the industrialized wo... more Great Britain has one of the lowest levels of traffic-related fatalities in the industrialized world with a current total of about 3500 fatalities per year. Large reductions have occurred over the last 20-30 years and the government has targets of achieving another 40% reduction by 2010. This paper analyzes some of the factors that have been statistically significant in helping to achieve those reductions with a focus on improvements in medical care and technology. Using a cross-sectional time-series of regional data a fixed effects negative binomial model is estimated which includes three proxies of medical care and technology changes. These are the average length of inpatient stay in the hospital, the per-capita level of National Health Service staff, and number of people per-capita waiting for hospital treatment. All are statistically significant with the expected sign showing that improvements in medical technology have reduced total fatalities with less of an impact from changes in medical care. Other variables are also found to be significant, including the percent of elderly people in the population, per-capita expenditure on alcohol, motorway capacity, and average vehicle age. The latter shows a surprisingly unexpected effect, with more older vehicles in a region leading to fewer fatalities. Models evaluating effects on serious and slight injuries are also estimated and serve to confirm the expected effects of medical care and technology.
Transportation Research Board 85th Annual MeetingTransportation Research Board, 2006
The objective of this paper is to quantify the effects of digital map quality and navigation data... more The objective of this paper is to quantify the effects of digital map quality and navigation data on the performance of map matching algorithms. Three map matching algorithms are tested with different digital maps (map scale 1:1250, 1:2500, and 1:50000) and navigation data (GPS and GPS augmented with DR) in order to quantify their performance. The algorithms are applied to different road networks of varying complexity. The performance of the algorithms is then assessed using high precision positioning data obtained from GPS carrier phase observables. The results show that there are considerable effects of digital map quality on the performance of map matching algorithms. However, the effects of navigation data are small for the test route analysed in this paper.
Transactions of Nanjing University of Aeronautics and Astronautics, Jun 1, 2005
This paper discusses a vehicle performance and emission monitoring system (VPEMS) capable of inte... more This paper discusses a vehicle performance and emission monitoring system (VPEMS) capable of interfacing with either a vehicle engine management system (EMS) or a sensor array fitted to the vehicle. It also describes the procedures used to validate the data generated by both diesel and petrol powered vehicles. These include the results of bench and field experiments using two instrumented vehicles and of experiments on a chassis dynamometer emissions test facility. The prototype VPEMS attains the specified performance levels for each of the subsystems, with aggregate mass emissions agreeing with the reference to within 11.5%, 8.1% and 17.7% for CO, CO2 and NO, respectively. The collation of these data to produce coherent spatially and temporally referenced databases of vehicle performance and the emission is demonstrated.
Transportation Research Board 87th Annual MeetingTransportation Research Board, 2008
The results from both time series and panel cointegration models are compared to estimate the eff... more The results from both time series and panel cointegration models are compared to estimate the effect that fares, income, quality of service and fuel prices have on the demand for the Mexico City metro in the period 1980-2005. Both approaches show that fares and fuel prices are not cointegrated with metro patronage, income and quality of service. The zero patronage response to fares suggests that either the vast majority of metro riders are transit dependent, or fare levels are too low relative to incomes that marginal changes do not affect patronage. The results also show that income elasticities are negative and close to unity in the long run, whilst service elasticities, measured by train kilometers operated per capita, have a positive but less than proportional effect on demand. Thus, service quality may need to improve proportionally more than income to maintain current patronage levels. Therefore, if a desired policy is to attract drivers to public transport, improvements in quality of service must be achieved rather than a reduction in fares. Likewise, if the aim is to improve the finances of the Mexico City metro, marginal fare increases may lead to higher revenue with no negative effects on patronage.
Gps Solutions, Mar 1, 2003
... Pollution, have documented these envi-ronmental impacts in terms of energy use, air ... Benef... more ... Pollution, have documented these envi-ronmental impacts in terms of energy use, air ... Benefits of integration and enhancement GIS and mapping Real-time mapping/location display. ... compared with the required navigation accuracy performance for fleet management given in ...
Transport Lessons from the Fuel Tax Protests of 2000, 2017
Transportation Research Board 88th Annual MeetingTransportation Research Board, 2009
The majority of evidence on gasoline demand elasticities is derived from models based on national... more The majority of evidence on gasoline demand elasticities is derived from models based on national data. Since the largest growth in population is now taking place in cities in the developing world it is important that we understand whether this national evidence is applicable to demand conditions at the local level. The aim of this paper is to estimate and compare gasoline per vehicle demand elasticities at the national and local levels in Mexico. National elasticities with respect to price, income, vehicle stock and metro fares are estimated using both a time series cointegration model and a panel GMM model for Mexican states. Estimates for Mexico City are derived by modifying national estimates according to mode shares as suggested by Graham and Glaister (2006), and by estimating a panel Within Groups model with data aggregated by borough. Although all models agree on the sign of the elasticities the magnitudes differ greatly. Elasticities change over time and differ between the national and local levels, with smaller price responses in Mexico City. In general, price elasticities are smaller than those reported in the gasoline demand surveys, a pattern previously found in developing countries. The fact that income and vehicle stock elasticities increase over time may suggest that vehicles are being used more intensively in recent years and that Mexico City residents are purchasing larger vehicles. Elasticities with respect to metro fares are negligible, which suggests little substitution between modes. Finally, the fact that fuel efficiency elasticities are smaller than vehicle stock elasticities suggests that vehicle stock size, rather than its composition, has a larger impact on gasoline consumption in Mexico City.
International Journal of Sustainable Transportation, 2011
ABSTRACT
Transport Policy, 2009
Time series cointegration techniques are used to estimate whether the Mexico City metro is percei... more Time series cointegration techniques are used to estimate whether the Mexico City metro is perceived as a normal or inferior good. Owing to the fact that the Mexico City metro mainly serves the low income sectors of the population, this paper attempts to separate the overall income effect into two uncorrelated components: a vehicle stock effect (used as a proxy for medium/high income) and minimum wage effect net of the influence of vehicle stock (used as a proxy for low income). The time series cointegration results show that minimum wage elasticities are positive whilst vehicle stock elasticities are negative. These results suggest that for the majority of metro users, whose salaries are based on low multiples of the minimum wage and are not potential car owners, the Mexico City metro is perceived as a normal good. However, for middle/high income earners, who can afford to buy a private vehicle when their incomes increase, the Mexico City metro is perceived as an inferior good.
Journal of Navigation, May 1, 2003
This paper describes the features of an extended Kalman filter algorithm designed to support the ... more This paper describes the features of an extended Kalman filter algorithm designed to support the navigational function of a real-time vehicle performance and emissions monitoring system currently under development. The Kalman filter is used to process global positioning system (GPS) data enhanced with dead reckoning in an integrated mode, to provide continuous positioning in built-up areas. The dynamic model and filter algorithms are discussed in detail, followed by the findings based on computer simulations as well as a limited field trial carried out in the Greater London area. The results of using the extended Kalman filter algorithm demonstrate that the integrated system employing GPS and low cost dead reckoning devices is capable of meeting the required navigation performance of the device under development.
Transportation Research Board 88th Annual MeetingTransportation Research Board, 2009
There is extensive research estimating the productivity gains from agglomeration economies, but t... more There is extensive research estimating the productivity gains from agglomeration economies, but there is a paucity of evidence on the spatial scale over which such benefits are available to firms and how they decay with distance. We show how commuting gravity-type models can be used to estimate the spatial decay of the benefits of agglomeration economies arising from labour pooling forces and perform estimation of such models using data on work trips for UK travel-to-work areas. Our findings show that the distance-decay parameter is smaller than the value commonly assumed in the empirical literature. This result suggests that the existing evidence could be underestimating the spatial scale of agglomeration externalities. In addition, we find that the size of the spatial decay gradient varies across employment areas. To investigate the variation of the distance-decay estimates we carry out a further piece of analysis by estimating a regression of the spatial decay estimates on a set of regressors thought to influence the value of the decay parameter. The results suggest that smaller distance-decay gradients are associated with more unbalanced spatial distribution of the resident population and employment, whereas it will be larger for employment areas with more diversified economic structures. On the other hand, we fail to find any significant contribution of access to transport infrastructure and attribute part of the explanation of this result to the limited ability of the measures to proxy for actual accessibility to economic activities.
Journal of Navigation, Apr 18, 2005
Map Matching (MM) algorithms are usually employed for a range of transport telematics application... more Map Matching (MM) algorithms are usually employed for a range of transport telematics applications to correctly identify the physical location of a vehicle traveling on a road network. Examples of such applications are in-car navigation systems, dynamic route guidance, fleet management, incident management, public transport management and real-time highway information provision. Two essential components for MM algorithms are (1) navigation sensors such as the Global Positioning System (GPS) and dead reckoning (DR), among others, to estimate the position of the vehicle, and (2) a digital base map for spatial referencing of the vehicle location. Previous research by the authors (Quddus et al., 2003; Ochieng et al., 2003) has developed improved MM algorithms that take account of the vehicle speed and the error sources associated with the navigation sensors and the digital map data previously ignored in conventional MM approaches. However, no validation study assessing the performance of MM algorithms has been presented in the literature. This paper describes a generic validation strategy and results for the MM algorithm previously developed in Ochieng et al (2003). The validation technique is based on a higher accuracy reference (truth) of the vehicle trajectory as determined by high precision positioning achieved by the carrierphase observable from GPS. The results show that the vehicle positions determined from the MM results are within 6m of the truth positions. The results also demonstrated the importance of the quality of the digital map data to the map matching process.
Transportation Research Record, 2004
This paper presents an analyses of pedestrian and bicycle casualties using cross-sectional time-s... more This paper presents an analyses of pedestrian and bicycle casualties using cross-sectional time-series data for the regions of Great Britain. A fixed effect negative binomial model is used which accounts for heterogeneity in the data and the distributional properties of count data. Various factors associated with those killed and seriously injured as well as slight injuries are examined. These include the average age of vehicles in the region, the road length of various road classes, the amount of vehicle ownership in the region, per capita income, per capita expenditure on alcohol, age cohorts, and various proxies for medical technology improvements. Various specifications of the models are estimated. Generally, we find that more serious pedestrian injuries are associated with lower income areas, increases in percent of local roads, increased per capita expenditure on alcohol, and total population. Statistical effects are harder to detect in models with serious injuries for bicyclists, but alcohol expenditure is strongly associated with increased injuries. This work has implications for transport policy aimed at increasing the modal share of pedestrians and bicyclists. Further research is needed to clearly understand some of the trends found in our analyses, especially the effect of changes in medical care and technology on total injuries.
Proceedings of the 17th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS 2004), Sep 24, 2004
... Y., Quddus, Mohammed A., Noland, Robert B., "Integrated Positioning Algorithms for T... more ... Y., Quddus, Mohammed A., Noland, Robert B., "Integrated Positioning Algorithms for Transport Telematics Applications," Proceedings of the 17th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS 2004), Long Beach, CA ...
Journal of Safety Research, Dec 1, 2002
Papers in Regional Science, Jun 1, 2009
Transportation Research Board 87th Annual MeetingTransportation Research Board, 2008
This paper investigates the relationship between firm formation and the availability of motorway ... more This paper investigates the relationship between firm formation and the availability of motorway and railway networks using data on Portuguese firm births for the periods 1995 and 2003. It develops an econometric model using micro level data in a geographic information system (GIS) to examine whether transport infrastructure has an impact on firm birth, to show how such impacts vary across industrial sectors, and to determine the relative magnitude of effects arising from rail and motorway networks. We conclude that the most significant factors influencing new firm birth are supply side variables and industrial economic structure. Labour costs and small firm size are strong significant locational determinants of firm births. Improvements in the railway and motorway networks do not appear to have a significant effect on new firm formation.
Transportation Research Board 89th Annual MeetingTransportation Research Board, 2010
This paper presents a model based on traffic count data to evaluate the potential effects of dist... more This paper presents a model based on traffic count data to evaluate the potential effects of distance-based road user charges in the Mexico City Metropolitan Area. The impact of marginal social cost pricing and environmental charges is assessed for both revenue raising and revenue neutral scenarios. Four user responses are allowed in the model: changes in vehicle occupancy, time switching, mode shift, and trip suppression. The model forecasts changes in traffic flows, speeds, public transport patronage and government revenue, for different area types and different times of the day. The results suggest that marginal social cost pricing would reduce traffic by about 14 percent and the revenues from the scheme would be equivalent to about 50 percent of the total Mexico City budget.
RePEc: Research Papers in Economics, Aug 1, 2003
A disaggregate spatial analysis, using enumeration district data for London was conducted with th... more A disaggregate spatial analysis, using enumeration district data for London was conducted with the aim of examining how congestion may affect traffic safety. It has been hypothesized that while congested traffic conditions may increase the number of vehicle crashes and interactions, their severity is normally lower than crashes under uncongested free flowing conditions. This is primarily due to the slower speeds of vehicles when congestion is present. Our analysis uses negative binomial count models to examine whether factors affecting casualties (fatalities, serious injuries and slight injuries) differed during congested time periods as opposed to uncongested time periods. We also controlled for congestion spatially using a number of proxy variables and estimated pedestrian casualty models since a large proportion of London casualties are pedestrians. Results are not conclusive. Our results suggest that road infrastructure effects may interact with congestion levels such that in London any spatial differences are largely mitigated. Some small differences are seen between the models for congested versus uncongested time periods, but no conclusive trends can be found. Our results lead us to suspect that congestion as a mitigator of crash severity is less likely to occur in urban conditions, but may still be a factor on higher speed roads and motorways.
A technically and economically feasible road user charging scheme should be based on quantities t... more A technically and economically feasible road user charging scheme should be based on quantities that are readily and accurately measurable, as well as being directly variable with the amount of road use and its impact on the environment and society. A key requirement for a pricing scheme is that the charging regime used should be easy for motorists to understand, but at the same time flexible enough for the operator to implement a wide range of policies to meet different aims. A set of variable road user charging indicators is identified herein by considering both the associated costs of a trip and the operational requirements for a feasible road pricing scheme. The study then focused on identifying a set of currently feasible technologies to measure these variables in real-time with high accuracy. Particular attention was paid to the need accurately to track vehicle movements and link these movements to geographical areas and road types, and the key pollutants and particulate matter, all of which have different potential effects that are in some cases dependent on location and time of emissions. Other issues, such as congestion measurement, are also discussed. (A)
RePEc: Research Papers in Economics, Aug 1, 2002
Great Britain has one of the lowest levels of traffic-related fatalities in the industrialized wo... more Great Britain has one of the lowest levels of traffic-related fatalities in the industrialized world with a current total of about 3500 fatalities per year. Large reductions have occurred over the last 20-30 years and the government has targets of achieving another 40% reduction by 2010. This paper analyzes some of the factors that have been statistically significant in helping to achieve those reductions with a focus on improvements in medical care and technology. Using a cross-sectional time-series of regional data a fixed effects negative binomial model is estimated which includes three proxies of medical care and technology changes. These are the average length of inpatient stay in the hospital, the per-capita level of National Health Service staff, and number of people per-capita waiting for hospital treatment. All are statistically significant with the expected sign showing that improvements in medical technology have reduced total fatalities with less of an impact from changes in medical care. Other variables are also found to be significant, including the percent of elderly people in the population, per-capita expenditure on alcohol, motorway capacity, and average vehicle age. The latter shows a surprisingly unexpected effect, with more older vehicles in a region leading to fewer fatalities. Models evaluating effects on serious and slight injuries are also estimated and serve to confirm the expected effects of medical care and technology.
Transportation Research Board 85th Annual MeetingTransportation Research Board, 2006
The objective of this paper is to quantify the effects of digital map quality and navigation data... more The objective of this paper is to quantify the effects of digital map quality and navigation data on the performance of map matching algorithms. Three map matching algorithms are tested with different digital maps (map scale 1:1250, 1:2500, and 1:50000) and navigation data (GPS and GPS augmented with DR) in order to quantify their performance. The algorithms are applied to different road networks of varying complexity. The performance of the algorithms is then assessed using high precision positioning data obtained from GPS carrier phase observables. The results show that there are considerable effects of digital map quality on the performance of map matching algorithms. However, the effects of navigation data are small for the test route analysed in this paper.
Transactions of Nanjing University of Aeronautics and Astronautics, Jun 1, 2005
This paper discusses a vehicle performance and emission monitoring system (VPEMS) capable of inte... more This paper discusses a vehicle performance and emission monitoring system (VPEMS) capable of interfacing with either a vehicle engine management system (EMS) or a sensor array fitted to the vehicle. It also describes the procedures used to validate the data generated by both diesel and petrol powered vehicles. These include the results of bench and field experiments using two instrumented vehicles and of experiments on a chassis dynamometer emissions test facility. The prototype VPEMS attains the specified performance levels for each of the subsystems, with aggregate mass emissions agreeing with the reference to within 11.5%, 8.1% and 17.7% for CO, CO2 and NO, respectively. The collation of these data to produce coherent spatially and temporally referenced databases of vehicle performance and the emission is demonstrated.
Transportation Research Board 87th Annual MeetingTransportation Research Board, 2008
The results from both time series and panel cointegration models are compared to estimate the eff... more The results from both time series and panel cointegration models are compared to estimate the effect that fares, income, quality of service and fuel prices have on the demand for the Mexico City metro in the period 1980-2005. Both approaches show that fares and fuel prices are not cointegrated with metro patronage, income and quality of service. The zero patronage response to fares suggests that either the vast majority of metro riders are transit dependent, or fare levels are too low relative to incomes that marginal changes do not affect patronage. The results also show that income elasticities are negative and close to unity in the long run, whilst service elasticities, measured by train kilometers operated per capita, have a positive but less than proportional effect on demand. Thus, service quality may need to improve proportionally more than income to maintain current patronage levels. Therefore, if a desired policy is to attract drivers to public transport, improvements in quality of service must be achieved rather than a reduction in fares. Likewise, if the aim is to improve the finances of the Mexico City metro, marginal fare increases may lead to higher revenue with no negative effects on patronage.
Gps Solutions, Mar 1, 2003
... Pollution, have documented these envi-ronmental impacts in terms of energy use, air ... Benef... more ... Pollution, have documented these envi-ronmental impacts in terms of energy use, air ... Benefits of integration and enhancement GIS and mapping Real-time mapping/location display. ... compared with the required navigation accuracy performance for fleet management given in ...
Transport Lessons from the Fuel Tax Protests of 2000, 2017