Skip to main content
Open Access Publications from the University of California

The Institute of Transportation Studies at UC Berkeley has supported transportation research at the University of California since 1948. About 50 faculty members, 50 staff researchers and more than 100 graduate students take part in this multidisciplinary program, which receives roughly $40 million in research funding on average each year. Alexandre Bayen, Professor of Civil and Environmental Engineering and Professor of Electrical Engineering and Computer Science, is its director.

Cover page of Understanding the Willingness to Share Resources in the Hurricane Irma Evacuation: A Multi-Modeling Approach

Understanding the Willingness to Share Resources in the Hurricane Irma Evacuation: A Multi-Modeling Approach


Recent technological improvements have greatly expanded the sharing economy (e.g., Airbnb, Lyft, and Uber), coinciding with growing need for transportation and sheltering resources in evacuations. To understand influencers on sharing willingness in evacuations, we employed a multi-modeling approach across four sharing scenarios using three model types: 1) four binary logit models that capture each scenario separately; 2) a multi-choice latent class choice model (LCCM) that jointly estimates multiple scenarios via latent classes; and 3) a portfolio choice model (PCM) that estimates dimensional dependency. We tested our approach by employing online survey data from 2017 Hurricane Irma evacuees (n=368).

The multi-model approach uncovered behavioral nuances undetectable with a single model. First, the multi-choice LCCM and PCM models uncovered scenario correlation, specifically willingness to share for both transportation scenarios and both sheltering scenarios. Second, the multi-choice LCCM found three classes – transportation sharers, adverse sharers, and interested sharers. Transportation sharers were more likely to be female, lower-income, and residents of Southwest Florida compared to adverse sharers. Interested sharers were more likely to be male, long-time residents, and higher-income compared to adverse sharers. Third, families with children were unwilling to share regardless of the model, while spare capacity (i.e., seatbelts, spare beds) had a positive but somewhat insignificant influence on sharing. Fourth, experienced home sharers were more willing to share shelter in the binary logit and PCM models. We suggest that local agencies consider holistic sharing mechanisms across resource types and time (i.e., before, during, and after a hurricane evacuation).

Cover page of Understanding California Wildfire Evacuee Behavior and Joint Choice-Making

Understanding California Wildfire Evacuee Behavior and Joint Choice-Making


For evacuations, people must make the critical decision to evacuate or stay followed by a multi-dimensional choice composed of concurrent decisions of their departure time, transportation mode, route, destination, and shelter type. These choices have important impacts on transportation response and evacuation outcomes. While extensive research has been conducted on hurricane evacuation behavior, little is known about wildfire evacuation behavior. To address this critical research gap, particularly related to joint choice-making in wildfires, we surveyed individuals impacted by the 2017 December Southern California Wildfires (n=226) and the 2018 Carr Wildfire (n=284). Using these data, we contribute to the literature in two key ways. First, we develop two simple binary choice models to evaluate and compare the factors that influence the decision to evacuate or stay. Mandatory evacuation orders and higher risk perceptions both increased evacuation likelihood. Individuals with children and with higher education were more likely to evacuate, while individuals with pets, homeowners, low-income households, long-term residents, and prior evacuees were less likely to evacuate. Second, we develop two portfolio choice models (PCMs), which jointly model choice dimensions to assess multi-dimensional evacuation choice. We find several similarities between wildfires including a joint preference for within-county and nighttime evacuations and a joint dislike for within-county and highway evacuations. To help build a transportation toolkit for wildfires, we provide a series of evidence-based recommendations for local, regional, and state agencies. For example, agencies should focus congestion reducing responses at the neighborhood level within or close to the mandatory evacuation zone.

Cover page of Urban Air Mobility: Viability of Hub-Door and Door-Door Movement by Air

Urban Air Mobility: Viability of Hub-Door and Door-Door Movement by Air


Owing to a century of innovation in connected and automated aircraft design, for the rst time in history, air transport presents a potential competitive alternative to road, for hub-to-door and door-to-door urban services. In this article, we study the viability of air transport, for moving people and goods in an urban area, based on three metrics - enroute travel time, fuel cost and carbon dioxide (CO2) emissions. We estimate the metrics from emission standards and operational assumptions on vehicles based on current market data and compare electric air travel to gasoline road travel. For passenger movement, air is faster than road for all distances. It fares better on fuel cost and emissions only for longer distances (specic transition distances are stated in the text). For consolidated movement of goods, air is at par with road. Finally, for movement of unconsolidated goods, air again fares better than road on all three metrics. It is also noteworthy that these results are based on a road friendly urban design. Changes in design that facilitate easier access to air based hub-to-door and door-to-door services, would only make the case stronger for Urban Air Mobility (UAM), especially with connected and automated aircraft, as the next revolution in urban transportation.

Cover page of The Producer Surplus Associated with Gasolne Fuel Use in the United States

The Producer Surplus Associated with Gasolne Fuel Use in the United States


Estimating the producer surplus – the revenue above the average long-run cost – is an important part of social cost-benefit analyses of changes in petroleum use. This paper estimates the producer surplus associated with changes in gasoline fuel use in the United States, and then applies the estimates of producer surplus to two kinds of social cost-benefit analyses related to petroleum use: (1) estimating the wealth transfer from consumers to producers as a result of policies that affect oil use and oil imports to the US, and (2) comparing the actual average cost of gasoline with the average cost of environmentally superior alternatives to gasoline, such as hydrogen. Our results show that a 50% reduction in gasoline use in the US in 2004 would have saved the US $72 billion in producer surplus payments to foreign oil producers. Applying our estimates to the comparison of the social lifetime cost of hydrogen vehicles versus gasoline vehicles, we find that inconsistently counting producer surplus from a US national perspective while counting climate change damages from a global perspective can overstate the present value lifetime costs of gasoline vehicles by $2,200 to $9,800 per vehicle.

Cover page of Intelligent Transportation Systems and Infrastructure A Series of Briefs for Smart Investments

Intelligent Transportation Systems and Infrastructure A Series of Briefs for Smart Investments


The last decade has witnessed an unprecedented convergence of communication, control, and sensing that can potentially transform transportation infrastructure and delivery. At the most basic level, efficient operation and maintenance of our nation’s transportation infrastructure requires real time data exchange provided by intelligent transportation system technology. When implemented, these technologies have the potential to revolutionize the nation’s economic vitality by moving people and goods more quickly, efficiently, safely, and at lower cost to consumers.

Cover page of Network Effects in Bus Transit: Evidence from Barcelona’s Nova Xarxa

Network Effects in Bus Transit: Evidence from Barcelona’s Nova Xarxa


This paper shows that improving the structure of a bus transit network to facilitate transfers can boost and shape its demand. The idea is illustrated with data from the Nova Xarxa in Barcelona. Deployed in phases, the Nova Xarxa is shown to be attracting more demand than the network it replaces. The paper further shows that this growth is underpinned by transfers -- at the end of 2015, the percentage of trips that involved a transfer was approximately 26%, and it reached a maximum of 57% for line V7. The paper shows these numbers should increase considerably (to 44% and 66%, respectively) once the Nova Xarxa is completed in 2018. This should be compared with the percent of transfers in other existing bus systems, which ranges from 1.3% to 16%.

Cover page of Dynamic Control of Complex Transit Systems

Dynamic Control of Complex Transit Systems


This paper proposes a dynamic control method to overcome bunching and improve the regularity of fixed-route transit systems. The method uses a combination of dynamic holding and en-route driver guidance to achieve its objectives. It applies to systems with a mix of headway-based and schedule-based lines but it is evaluated for scheduled systems as this is the more challenging application. Improved schedule adherence is the goal. The method’s calculation complexity per piece of advice does not increase with system size. As a result, the method is scalable and can be used with large multiline systems, no matter how complex. When controled, each vehicle is mostly affected by exogenous disturbances (e.g. traffic) and very little by other vehicles. As a result, disruptions to a vehicle or group of vehicles caused by inattentive drivers or control equipment failures remain confined to the vehicles experiencing the problems. The control method effectively quarantines “disease”. The method is evaluated analytically and with simulations over a broad range of conditions, including schedules with zero slack. The method was also evaluated by observing the performance of a real world multi-line system that uses inexpensive on-board tablets to apply the control. The evaluation addresses driver compliance and equipment malfunction issues. It is found that the method is resilient and improves reliability considerably even under challenging conditions.

Cover page of Inclusionary Zoning in a Monocentric City

Inclusionary Zoning in a Monocentric City


To show how inclusionary zoning alters development, the author finds the most profitable housing design to build on vacant lots at each location in a monocentric city under different regulatory regimes. Section 1 sets up the model by specifying renter's preferences, geography and building parameters. Section 2 solves the developer's profit-maximization problem at each location under each regime. Finally, in Section 3, a numerical simulation confirms the effects predicted by theory and gives a picture of their magnitude.