conference paper

Envy-free pricing for collaborative consumption of supply in transportation systems

Papers selected for the 22nd international symposium on transportation and traffic theory

Publication Date

January 1, 2017

Author(s)

Roger Lloret-Batlle, R. (Jay) Jayakrishnan

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Abstract

Consumption of supply in transportation systems has generally always followed a First-Come-First-Served (FCFS) rule. This article proposes new control policies based on the concept of envy-freeness which outperform FCFS in both efficiency and fairness. We call an allocation envy-free when no agent feels any other agent’s allocation to be better than their own, at the current price. Envy-free allocations are thus considered fair. Several new contributions are made: we first present a conceptual theoretical supply demand framework which formally introduces the new supply paradigm. We propose and simulate a new problem, queue jumping operations on highways, in which vehicles can skip positions in a queue and compensate the overtaken vehicles with a payment. We present a new concept, dynamic envy-freeness, and provide a new envy ranking criterion, Constant Elasticity of Substitution Envy Intensity (CESEI) that is applied to PEXIC, an exchange-based traffic signal control scheme. (C) 2017 The Authors. Elsevier B.V. All rights reserved.

Suggested Citation

Roger Lloret-Batlle and R. Jayakrishnan (2017) “Envy-free pricing for collaborative consumption of supply in transportation systems”, in . Mahmassani, H and Nie, Y and Smilowitz, K (ed.) Papers selected for the 22nd international symposium on transportation and traffic theory. ELSEVIER SCIENCE BV (Transportation research procedia), pp. 772–789. Available at: 10.1016/j.trpro.2017.05.043.

research report

Transit Investment Impacts on Land Use Beyond the Half-Mile Mark

Publication Date

June 1, 2017

Associated Project

Transit Investment Impacts on Land Use Beyond the Half-Mile Mark

Author(s)

Jae Hong Kim, Doug Houston, Jaewoo Cho, Wan-Tzu (Ashley) Lo, Naila Sharmeen

Areas of Expertise

Public Transit, Shared Mobility, & Active Transportation Travel Behavior, Land Use, & the Built Environment

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Abstract

This project examines the impacts of light rail transit investments on broader vicinity areas in Los Angeles County. This project found that the land use impacts of public transit investments are not necessarily confined to the half-mile boundary around station areas, although substantial variation exists by transit line. While the areas beyond the half-mile mark were often excluded from conventional transit-oriented planning processes, these areas show a distinct pattern of land use transformation. Areas beyond the half-mile mark had a higher rate of development for several urban purposes, particularly after a few years have elapsed since the opening of nearby transit lines/stations.

Suggested Citation

Jae Hong Kim, Douglas Houston, Jaewoo Cho, Ashley Lo and Naila Sharmeen (2017) Transit Investment Impacts on Land Use Beyond the Half-Mile Mark. Available at: https://escholarship.org/uc/item/6cv0d1rs (Accessed: October 11, 2023).

Related Publications

policy brief | May 2019

Transit Investments are Having an Impact on Land Use Beyond the Half-Mile Mark

Phd Dissertation

Automated Identification of Near-Stationary Traffic States and Calibration of Unifiable Multi-Lane Multi-Class Fundamental Diagrams

Publication Date

January 1, 2018

Author(s)

Qinglong (Louis) Yan

Areas of Expertise

Infrastructure Delivery, Operations, & Resilience Intelligent Transportation Systems, Emerging Technologies, & Big Data

View Phd Dissertation

Abstract

Experience of daily commuters shows that stationary traffic patterns can be observed during peak periods in urban freeway networks. Such stationary states play an important role in various traffic flow studies. Conceptually, studies on the impact of capacity drop and design of traffic control strategies have been built on the assumption of stationarity. Mathematically, the existence and stability of stationary states in general road networks have been proved. Empirically, near-stationary states have been utilized for calibration of fundamental diagrams and investigation of traffic features at freeway bottlenecks. Therefore, an imperative need for real-world near-stationary data has been realized to better understand, investigate, and explore such above studies. However, there lacks an efficient method to identify near-stationary states. To fill the gap, in this research, an automated method has been developed to efficiently identify near-stationary states from large amounts of inductive loop-detector data. The method consists of four steps: first, a data pre-processing technique is performed to select healthy datasets, fill in missing values, and normalize vehicle counts and occupancies; second, a PELT changepoint detection method is adopted to detect changes in means and partition time series into candidate intervals; third, informative characteristics of each candidate, including duration and gap, are defined and calculated; finally, near-stationary states are selected from candidates through duration and gap criteria. A game theory approach is further designed to directly calibrate parameters of the above method. First, a multi-objective optimization problem is formulated to consider the quantity and quality of near-stationary states as the objective functions. Then the problem is converted into a non-cooperative game with at least one Nash equilibrium. To solve the game and obtain a unique solution, an alternated hill-climbing search algorithm is developed. Furthermore, two calibration schemes for multi-lane and multi-class fundamental diagrams are respectively designed by utilizing near-stationary states. Such multi-commodity fundamental diagrams possess unifiable and non-FIFO properties and can capture interaction among different commodities. Calibration and validation results show that both the calibrated unifiable multi-lane and multi-class fundamental diagrams are well-fitted, physically meaningful, and have robust performance on the estimation of commodity flow-rates.

Suggested Citation

Qinglong Yan (2018) Automated Identification of Near-Stationary Traffic States and Calibration of Unifiable Multi-Lane Multi-Class Fundamental Diagrams. Ph.D.. UC Irvine. Available at: https://escholarship.org/uc/item/74z844j2 (Accessed: October 12, 2023).

Phd Dissertation

Active Travel, Built Environment and Transit Access: A Micro-Analysis of Pedestrian Travel Behavior

Publication Date

January 1, 2014

Author(s)

Gaby Abdel-Salam

Areas of Expertise

Travel Behavior, Land Use, & the Built Environment

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Abstract

The introduction of Senate Bill (SB 375) in 2008 stimulated more research linking travel behavior to the built environment. Smart growth tools mandated by this bill aim to reduce vehicle miles traveled (VMT), greenhouse gas (GhG) emissions and promote alternative modes to motorized travel. These tools encompass an array of land use improvements that are expected to influence active travel. Potential changes in the built environment may impact the frequency, amount and even the selection of routes for walking. Data used in this dissertation was obtained from Phase I of the Expo Study, a three-phase travel survey of residents living near the Expo Light Rail Line in Los Angeles, CA. Respondents carried GPS devices and accelerometers to track locations and activity levels; and completed seven-day trip logs. Phase I of the survey was administered in Fall 2011, prior to the introduction of the Expo Line in April 2012.This dissertation is comprised of three research topics. The first topic uses a “place-oriented” approach to examine where active travel occurs in neighborhoods adjacent to the Expo Light Rail Line. This chapter is based on the Behavioral Model of Environments, which emphasizes the influence of the physical environment on individuals’ travel behavior and route choices. Results indicate that the routes selected by pedestrians have higher densities of commercial and retail centers and better access to more transit stations. The second research topic uses an ecological modeling approach. Multilevel analysis of the effects of the built environment on active transport was performed in three geographic levels of aggregation near respondents’ homes. Examination of land uses at the half-mile extent yield the least number of significant results. In contrast, land uses examined at the segment-level and quarter-mile distance from homes emphasize the importance of street connectivity and green space on increasing transport-related physical activity (TPA). This suggests the importance of analyzing the data at finer geographic levels.The third research topic proposes a practical methodology of pedestrian route analysis in which observed GPS-tracked routes were examined and compared to GIS-simulated shortest paths. The two route types were compared over deviations in trip-level travel indices, respondents’ socio-demographic traits, time of day variations and differences in objectively measured built environment features along both sets of routes. Results suggest that observed routes diverged more from shortest paths with increasing distance and were more circuitous beyond the 2.4-mile threshold. Most walks were completed after the AM Off Peak time. With the exception of the Evening time, observed routes were found to be much longer in all time periods especially in the AM Peak time. Moreover, higher densities of commercial centers, local businesses and green spaces were observed more for GPS-tracked routes than for shortest paths. These routes also had more street intersections and transit stops. Overall, results imply that pedestrians selected routes that were longer than the respective shortest paths and that may have been due to greater access to amenities and activity centers.

Suggested Citation

Gaby Hamdi Abdel-Salam (2014) Active Travel, Built Environment and Transit Access: A Micro-Analysis of Pedestrian Travel Behavior. UC Irvine. Available at: https://uci.primo.exlibrisgroup.com/permalink/01CDL_IRV_INST/1gpb62p/alma991003059819704701 (Accessed: October 12, 2023).

conference paper

Integration of weigh-in-motion and inductive signature technology for advanced truck monitoring

93rd annual meeting of the transportation research board, washington, DC

Publication Date

January 1, 2014

Author(s)

Sarah Hernandez, Andre (Yeow Chern) Tok, Stephen Ritchie

Suggested Citation

Sarah Hernandez, Andre Tok and Stephen G Ritchie (2014) “Integration of weigh-in-motion and inductive signature technology for advanced truck monitoring”, in 93rd annual meeting of the transportation research board, washington, DC.

published journal article

Urban general equilibrium models with non-central production*

Journal of Regional Science

Publication Date

August 1, 1978

Author(s)

Jan Brueckner

View published journal article

Suggested Citation

Jan K. Brueckner (1978) “Urban general equilibrium models with non-central production*”, Journal of Regional Science, 18(2), pp. 203–215. Available at: 10.1111/j.1467-9787.1978.tb00542.x.

published journal article

Maternal exposure to ambient air pollution mixture and premature rupture of membranes: Evidence from a large cohort in Southern California (2008–2018)

Environment International

Publication Date

July 1, 2023

Author(s)

Anqi Jiao, Yi Sun, Chantal Avila, Vicki Chiu, John Molitor, Jeff Slezak, David A. Sacks, Jiu-Chiuan Chen, Tarik Benmarhnia, Darios Getahun, Jun Wu

View published journal article

Abstract

Background There is minimal evidence of relationships between maternal air pollution exposure and spontaneous premature rupture of membranes (SPROM), a critical obstetrical problem that can significantly increase maternal and fetal mortality and morbidity. No prior study has explored the PROM risk related to specific components of particulate matter with aerodynamic diameters of ≤ 2.5 µm (PM2.5). We examined associations between maternal exposure to nitrogen dioxide (NO2), ozone (O3), PM2.5, PM10, and PM2.5 constituents and SPROM. Methods A large retrospective cohort study was conducted and included 427,870 singleton live births from Kaiser Permanente Southern California during 2008–2018. Monthly averages of NO2, O3 (8-h daily maximum), PM2.5, and PM10 were measured using empirical Bayesian kriging based on measurements from monitoring stations. Data on PM2.5 sulfate, nitrate, ammonium, organic matter, and black carbon were obtained from a fine-resolution model. A discrete time approach with pooled logistic regressions was used to estimate associations throughout the pregnancy and based on trimesters and gestational months. The quantile-based g-computation models were fitted to examine the effects of 1) the air pollution mixture of four pollutants of interest and 2) the mixture of PM2.5 components. Results There were 37,857 SPROM cases (8.8%) in our study population. We observed relationships between SPROM and maternal exposure to NO2, O3, and PM2.5. PM2.5 sulfate, nitrate, ammonium, and organic matter were associated with higher SPROM risks in the single-pollutant model. Mixture analyses demonstrated that the overall effects of the air pollution mixture and PM2.5 mixture in this study were mainly driven by O3 and PM2.5 nitrate, respectively. Underweight mothers had a significantly higher risk of SPROM associated with NO2. Conclusion Our findings add to the literature on associations between air pollution exposure and SPROM. This is the first study reporting the impact of PM2.5 constituents on SPROM.

Suggested Citation

Anqi Jiao, Yi Sun, Chantal Avila, Vicki Chiu, John Molitor, Jeff Slezak, David A. Sacks, Jiu-Chiuan Chen, Tarik Benmarhnia, Darios Getahun and Jun Wu (2023) “Maternal exposure to ambient air pollution mixture and premature rupture of membranes: Evidence from a large cohort in Southern California (2008–2018)”, Environment International, 177, p. 108030. Available at: 10.1016/j.envint.2023.108030.

Phd Dissertation

Computational Models for Scheduling in Online Advertising

Publication Date

June 30, 2016

Author(s)

Dmitri Arkhipov

Areas of Expertise

Travel Behavior, Land Use, & the Built Environment

View Phd Dissertation

Abstract

Programmatic advertising is an actively developing industry and research area. Some of the research in this area concerns the development of optimal or approximately optimal contracts and policies between publishers, advertisers and intermediaries such as ad networks and ad exchanges. Both the development of contracts and the construction of policies governing their implementation are difficult challenges, and different models take different features of the problem into account. In programmatic advertising decisions are made in real time, and time is a scarce resource particularly for publishers who are concerned with content load times. Policies for advertisement placement must execute very quickly once content is requested; this requires policies to either be pre-computed and accessed as needed, or for the policy execution to be very efficient. We formulate a stochastic optimization problem for per publisher ad sequencing with binding latency constraints. Within our context an ad request lifecycle is modeled as a sequence of one by one solicitations (OBOS) subprocesses/lifecycle stages. From the viewpoint of a supply side platform (SSP) (an entity acting in proxy for a collection of publishers), the duration/span of a given lifecycle stage/subprocess is a stochastic variable. This stochasticity is due both to the stochasticity inherent in Internet delay times, and the lack of information regarding the decision processes of independent entities. In our work we model the problem facing the SSP, namely the problem of optimally or near-optimally choosing the next lifecycle stage of a given ad request lifecycle at any given time. We solve this problem to optimality (subject to the granularity of time) using a classic application of Richard Bellman’s dynamic programming approach to the 0/1 Knapsack Problem. The DP approach does not scale to a large number of lifecycle stages/subprocesses so a sub-optimal approach is needed. We use our DP formulation to derive a focused real time dynamic programming (FRTDP) implementation, a heuristic method with optimality guarantees for solving our problem. We empirically evaluate (through simulation) the performance of our FRTDP implementation relative to both the DP implementation (for tractable instances) and to several alternative heuristics for intractable instances. Finally, we make the case that our work is usefully applicable to problems outside the domain of online advertising.

Suggested Citation

DMITRI ARKHIPOV (2016) Computational Models for Scheduling in Online Advertising. PhD Dissertation. UC Irvine. Available at: https://uci.primo.exlibrisgroup.com/permalink/01CDL_IRV_INST/1gpb62p/alma991001362249704701.

Phd Dissertation

Mediating change and changes in mediation: Adapting ICTs for just environmental governance

Publication Date

January 1, 2010

Author(s)

C. Smith

Areas of Expertise

Intelligent Transportation Systems, Emerging Technologies, & Big Data Travel Behavior, Land Use, & the Built Environment

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Abstract

Information and communication technologies (ICTs) are important research areas for scientists examining theories of communication, conflict resolution and collaborative decision-making, particularly because they offer impressive analytical capabilities and the capacity to integrate different modes of deliberation and forms of content. The exponential growth in the adoption and diffusion of these digital media currently has, and will likely continue to have, considerable social ecological implications in part because ICTs are increasingly positioned as places of convergence for politically contested information and knowledge. However, the nature of these implications, especially questions concerning how these technologies influence or mediate changes in policy and/or the policymaking process itself is unclear and controversial. Technological enthusiasts, for example, argue that ICTs have potential to upgrade democracy by improving the way we devise means to clarified ends whereas technological pessimists challenge that, far from ushering in a new age of democracy, new media technologies actually hinder coordinative action by reducing more personalized modes of communication. This research examined both face-to-face and online communication facilitated by three institutions in California—the South Coast Air Quality Management District (SCAQMD), the California Environmental Justice Action Committee (CEJAC) and Communities for a Better Environment (CBE)—as they sought to reach decisions concerning a series of environmental justice-related issues. Informed by a mixed methodological approach, this research characterizes the challenges and opportunities afforded by the traditional face-to-face (F2F) settings hosted by the three organizations (i.e., public hearings, public meetings and workshops, respectively) and communication within these settings differed from and integrated with EJ communication in the institutions’ corresponding new media or ICT-based environments (i.e., general content websites and interactive mapping applications). The research found that, while there were obvious limitations to F2F participation, the pragmatic modes of communication that took place in these three settings were not replicated in the online environment. Most troublesome was that ICT-based communication tended to be less trustworthy, interactive and coherent than corresponding communication in F2F settings. The dissertation concludes by putting forth an alternative ICT-based framework for just environmental governance that enables interdependent, multi-directional and adaptive forms of knowledge production and decision-making.

Suggested Citation

C. Scott Smith (2010) Mediating change and changes in mediation: Adapting ICTs for just environmental governance. Ph.D.. University of California, Irvine. Available at: https://uci.primo.exlibrisgroup.com/permalink/01CDL_IRV_INST/1gpb62p/alma991007626549704701 (Accessed: October 13, 2023).

policy brief

California Can Simplify the Housing Element Law to Reduce Administrative Burdens and Improve Social Equity

Publication Date

February 1, 2021

Author(s)

Huixin (Echo) Zheng, Nicholas Marantz, Doug Houston, Jae Hong Kim

View policy brief

Abstract

California’s Housing Element law requires all local governments to adequately plan to meet the state’s existing and future housing needs. The law establishes processes for determining regional housing needs and requires regional councils of governments (COGs) with allocating these housing needs to cities and counties in the form of numerical targets. Local governments must update the housing element of their general plans and adopt policies to accommodate the housing targets. The California Department of Housing and Community Development (HCD) reviews all local housing elements and determines whether the elements comply with state law.

Suggested Citation

Huixin Zheng, Nicholas J. Marantz, Doug Houston and Jae Hong Kim (2021) California Can Simplify the Housing Element Law to Reduce Administrative Burdens and Improve Social Equity. Policy Brief. Available at: https://escholarship.org/uc/item/7p94n1cd (Accessed: October 11, 2023).