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The Sacramento, California region is engaged in an innovative long-range visioning process during 2004 and 2005, where the regional transportation planning agency is defining and modeling several 50-year growth scenarios. We worked with environmental and social equity citizens groups to define policies that would reduce emissions, serve lower-income travelers better, and preserve habitats and agricultural lands in the region. The citizens groups rejected the new freeways planned for the region, as well as the substantial freeway widenings for HOV lanes. In addition, they defined a more-ambitious transit system, involving new Bus Rapid Transit lines and shorter headways for all rail and bus service. This transit-only plan was modeled, by itself, and along with a land use policy for an urban growth boundary and a pricing policy for higher fuel taxes and parking charges for worktrips. We used a new version of the MEPLAN model to simulate these scenarios over 50 years and describe our findings regarding total travel, mode shares, congestion, emissions, land use changes, and economic welfare of travelers.

In the past ten years, integrated land use and transportation modeling has received considerable attention in the scholarly literature. This academic interest is slowly yielding practical applications. Many metropolitan planning organizations (MPOs) and state departments of transportation are beginning to implement these types of models for the first time. While many improvements have been made to these models, and the value of these improvements should not be understated, much work still remains. One of the most challenging problems in land use modeling is how floorspace (buildings) is built and occupied. The purpose of this paper is twofold: first, to draw attention to insufficiencies in the representation of floorspace developer behavior—particularly as it applies to large, urban-edge projects—within current integrated land use and transportation models and, second, to determine the necessity of explicitly accounting for such projects within these models. The Sacramento MEPLAN model will be used together with historical development records to demonstrate and test these assertions. Single large developments are modeled with a common year of development, size, and location. Among the findings, large developments are fairly common in the Sacramento region and make up a considerable amount of floorspace development in absolute terms, large basic sector developments have more of an impact and are therefore more important to explicitly account for than are large non-basic sector developments. A single large basic sector development modeled in a 20 year forecast has a significant impact on zonal outputs. Recommendations are put forward regarding the use of this research in practical modeling exercises.

Traveler behavior plays a role in the effectiveness of travel demand management (TDM) policies. Personal travel management is explored in this paper by analyzing individuals’ adoption and consideration of 17 travel-related alternatives in relation to socio-demographic, mobility, travel-related attitude, personality and lifestyle preference variables. The sample comprises 1282 commuters living in urban and suburban neighborhoods of the San Francisco Bay Area. Among the findings: females were more likely to have adopted/considered the more ‘costly’ strategies; those with higher mobility were more likely to have adopted/considered travel-maintaining as well as travel-reducing strategies; and those who like travel and want to do more are less likely to consider travel-reducing strategies. These findings, when combined with those of earlier work on this subject, present a compelling argument for the need to further understand traveler behavior -- particularly in response to congestion and TDM policies.

We describe our experience teaching an overview course on urban modeling for graduate students at the University of California, Davis. It was decided at the outset that we would let the students run actual calibrated models in this class. This may be the first course where students were exposed to GIS models, as well as to spatial competition (economic) models. We conclude that the active learning format was successful in getting the students to understand the purposes of the various types of models and their limitations.

Integrated land use and transportation forecasting models are used to assist decision-makers in the policy analysis and infrastructure capital improvement selection process. These models are typically given precise, point-estimate inputs that are mathematically linked, through a series of submodels, to forecasted model outputs. These point-estimate inputs represent an unrealistic level of precision and a growing body of research is focusing on statistical techniques to model uncertainty in model inputs and parameters and tracking the effects of this uncertainty through the various submodels to the model outputs. This paper presents an uncertainty analysis of the Large Zone Economic Module (LZEM) of the Simple, Efficient, Elegant, and Effective Model (SE3M) of land use and transportation. Three case-study implementations of the model are used to obtain a reasonably sound approximation of how uncertainty affects LZEM outputs: Guam, Puerto Rico, and Oahu, Hawaii. These case studies were the subject of an early transferability study with SE3M and were selected based on both their insularity and diverse physical, economic, and demographic geographies. The findings of this research demonstrate that LZEM has a robust framework, with the potential to estimate error both in the positive and negative direction under uncertain input/parameter conditions. [ABSTRACT FROM PUBLISHER]

Integrated land use/transportation forecasting models add significant policy and infrastructure alternatives analysis capabilities to the urban planning process. Historically, the financial, time, and staff requirements to develop one of these models has put them beyond the reach of most small- to medium-sized urban areas. The purpose of this paper is to present the large zone economic submodel of SE3M, an integrated model – founded upon economic base theory and bid-rent theory – that is reasonably accurate, yet simpler in form, function, and implementation than competing models. The US territory of Guam is used as the case study/proof of concept implementation for this model framework. The submodel presented here was validated against a horizon year with known data for zonal level population and employment totals together with control totals for the island as a whole. The model was able – across two base years and one validation, horizon year – to locate all jobs and a high percentage of the population on each zone on the island. [ABSTRACT FROM PUBLISHER]