Hai Yang

Hai Yang
The Hong Kong University of Science and Technology | UST

About

224
Publications
34,169
Reads
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10,783
Citations
Citations since 2016
81 Research Items
6145 Citations
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201620172018201920202021202202004006008001,000
201620172018201920202021202202004006008001,000

Publications

Publications (224)
Preprint
Over the past two decades, bike-sharing systems have grown significantly worldwide. Compared with that of other business sectors, the means by which revenue is obtained in the bike-sharing industry is unique. When the market in a region or city is saturated, an efficient way for a firm to increase revenue is to enter into a new market. In this stud...
Article
Ride-sourcing services have become increasingly important in meeting people's mobility needs since their emergence. Compared to traditional street-hailing taxi services, ride-sourcing services significantly reduce the matching frictions in the markets by matching drivers and passengers with relatively distant distances through an online platform. M...
Article
The current revolutions of automation, electrification, and sharing are reshaping the way we travel, with broad implications for future mobility management. While much uncertainty remains about how these disruptive technologies would exactly impact demand for future mobility and enhancement of transportation supply, it is clear that innovative dema...
Article
On-demand matching between waiting passengers and idle drivers is one of the most important components in a ride-sourcing system. A variety of matching mechanisms have been developed to meet different needs of ride-sourcing platforms, e.g. mitigating supply–demand imbalance, maximizing platform revenue. In this paper, we focus on a block matching s...
Article
This paper proposes an algorithm for solving the schedule-based passenger assignment problem, with explicit consideration of continuous time-varying demand and tight capacity constraints for large-scale high-speed railway (HSR) networks. We construct the space-time travel network and formulate the assignment model by destination-based arc flow vari...
Article
This paper proposes a general model for describing the equilibrium state of a ride-sourcing market with an arbitrary number of platforms competing with each other. As the number of platforms increases, the market changes from monopoly to duopoly, oligopoly, and finally perfect competition, bringing about two different effects on system efficiency....
Article
This paper proposes an equilibrium model to describe a ride-sourcing market with both ride-pooling (RP) and non-pooling (NP) services considering traffic congestion externality. In particular, we develop a deductive model to approximate the pool-matching probability and passengers’ expected waiting time under a pre-assigned pool-matching mechanism...
Preprint
Full-text available
This paper proposes an algorithm for solving the schedule-based passenger assignment problem, with explicit consideration of continuous time-varying demand and tight capacity constraints for large-scale high-speed railway (HSR) networks. We construct the space-time travel network and formulate the assignment model by destination-based arc flow vari...
Article
A parking sharing platform plays the role of a matchmaker between parking ‘slot owners/sharers’ and ‘slot renters’ who demand parking. The platform can act as either a reseller or a commissioner, and can have different economic objectives when setting prices for owners and renters. This paper is the first to address a platform operator’s pricing st...
Article
Over the past two decades, bike-sharing systems have grown significantly worldwide. Compared with that of other business sectors, the means by which revenue is obtained in the bike-sharing industry is unique. When the market in a region or city is saturated, an efficient way for a firm to increase revenue is to enter a new market. In this study, we...
Article
Ride-sourcing services have become an integral part of urban transportation systems. In a cooperative relationship with the platform, ride-sourcing drivers have the flexibility to work according to their habits or preferences, which could constitute heterogeneous working pattern(s) among drivers. Based on real-world ride-sourcing data, we analyze d...
Preprint
Full-text available
A parking sharing platform plays the role of a matchmaker between parking 'slot owners/sharers' and 'slot renters' who demand parking. The platform can act as either a reseller or a commissioner, and can have different economic objectives when setting prices for owners and renters. This paper is the first to address a platform operator's pricing st...
Article
Fitting and modeling spatial-temporal processes are essential research topics in transportation studies. Recently, due to the analytically tractable formulation and good fitting accuracy, the Gaussian Process (GP) is becoming increasingly preferable in fitting transportation processes. However, conventional GPs are inapplicable for large-scale prob...
Article
Ebike-sharing (electric bicycle-sharing) systems are gaining popularity as ebikes provide riders with transportation convenience when people have limited accessibility to other travel modes. Compared to traditional bike-sharing systems, ebike-sharing systems are more complicated as the platform needs to handle battery recharging issues as well as t...
Article
Combining ride-sourcing and public transit services (with ride-sourcing service to address the first/last-mile issues) can bring many benefits, such as saving passengers’ trip fares, improving drivers’ earnings, reducing gas emissions, and alleviating traffic congestion. However, it still remains a challenging issue to coordinate ride-sourcing and...
Article
This study examines the pricing strategy of a parking sharing platform that rents the daytime-usage rights of private parking spaces from parking owners and sells them to parking users. In an urban area with both shared parking and curbside parking, a choice equilibrium model is proposed to predict the number of shared parking users under any given...
Article
Recently, some third-party integrators attempt to integrate the ride services offered by multiple independent ride-sourcing platforms. Accordingly, passengers can request ride through the integrators and receive ride service from any one of the ride-sourcing platforms. This novel business model, termed as third-party platform-integration in this wo...
Article
As demands for convenient and comfortable mobility grow, transportation network companies (TNCs) begin to diversify the ride-hailing services they offer. Modes that are offered now include ride-pooling (RP), non-ride-pooling (NP), and a third “bundled” option, which combines RP and NP. This emerging bundled option allows riders to be served via eit...
Article
Ride-sourcing services have experienced dramatic growth over the past decade but aroused debates on whether and how the government should regulate the ride-sourcing platform. To tackle this critical issue, this paper investigates the regulatory outcomes of various representative government regulations, including price-cap regulation, vehicle fleet...
Article
Ride-sourcing drivers spend a significant portion of their service time being idle, during which they can move freely to search for the next customer. Such customer-searching movements, while not being directly controlled by ride-sourcing platforms, impose great impacts on the service efficiency of ride-sourcing systems and thus need to be better u...
Article
The substitution and complement of ride-sourcing services and public transit services greatly affect the mobility and accessibility of a multi-modal transportation system. Since the transportation network company (TNC) (operator of ride-sourcing) concerns the profit and the government (operator of public transit) promotes social welfare, the two po...
Preprint
Full-text available
This study examines the pricing strategy of a parking sharing platform that rents the daytime-usage rights of private parking spaces from parking owners and sells them to parking users. In an urban area with both shared parking and curbside parking, a choice equilibrium model is proposed to predict the number of shared parking users under any given...
Article
This paper models the joint equilibrium of destination and parking choices in cities under hybrid supply of curbside parking and shared parking. Given the parking supply (capacities and prices), the joint equilibrium of destination and parking choices is formulated as a variational inequality problem. We then discuss the existence and uniqueness/no...
Article
In oversaturated urban rail transit systems, passengers departing from downstream stations often experience long waiting times due to unbalanced space-time demand and limited transit capacity. This is often prevalent during morning and evening peak periods in transit systems. This paper aims to mitigate the unfairness of waiting time among a time-v...
Preprint
Full-text available
This paper models the joint equilibrium of destination and parking choices in cities under hybrid supply of curbside parking and shared parking. Given the parking supply (capacities and prices), the joint equilibrium of destination and parking choices is formulated as a variational inequality problem. We then discuss the existence and uniqueness/no...
Preprint
Full-text available
Data-driven approaches have been applied to many problems in urban computing. However, in the research community, such approaches are commonly studied under data from limited sources, and are thus unable to characterize the complexity of urban data coming from multiple entities and the correlations among them. Consequently, an inclusive and multifa...
Article
Ride-hailing platforms generally provide various service options to customers, such as solo ride services, shared ride services, etc. It is generally expected that demands for different service modes are correlated, and the prediction of demand for one service mode can benefit from historical observations of demands for other service modes. Moreove...
Article
This study models spatiotemporal passenger flow distribution for high-speed railway (HSR) networks with capacity constraints. The HSR travel demand involves two time-dimensions, i.e., the ticket booking time and the desired departure time. Under the principle of first-booked-first-served, a passenger flow assignment model is formulated, where a lat...
Article
For on-demand service platforms in general (including food, grocery, and fresh-product delivery platforms) and, in particular, shared-mobility service systems, customers are plausibly heterogeneous in their private delay sensitivity and preference for products. This paper develops incentive contracts with substitution or non-substitution strategies...
Article
Mathematical modeling of epidemic spreading has been widely adopted to estimate the threats of epidemic diseases (i.e., the COVID-19 pandemic) as well as to evaluate epidemic control interventions. The indoor place is considered to be a significant epidemic spreading risk origin, but existing widely-used epidemic spreading models are usually limite...
Article
The emerging on-demand ride-sourcing programs provided by transportation network companies (TNCs) have been reshaping the transportation industry. Research efforts in this area have covered topics such as supply-demand equilibrium, pricing, matching, dispatching, but have not fully spread to the potential impacts of ride-sourcing on public transit...
Preprint
Full-text available
This study models spatiotemporal passenger flow distribution for high-speed railway (HSR) networks with capacity constraints. The HSR travel demand involves two time-dimensions, i.e., the ticket booking time and the desired departure time. Under the principle of first-booked-first-served, a passenger flow assignment model is formulated, where a lat...
Article
Ride-hailing service has witnessed a dramatic growth over the past decade but meanwhile raised various challenging issues, one of which is how to provide a timely and accurate short-term prediction of supply and demand. While the predictions for zone-based demand have been extensively studied, much less efforts have been paid to the predictions for...
Article
In the era of transportation big data, the analysis of mobility patterns generally involves large quantities of datasets with high-dimensional variables recording individual travelers' activities and socioeconomic attributes, bringing new challenges to researchers. Conventional regression-based models commonly require complex structures in depictin...
Article
By serving two or more passenger requests in each ride in ride-sourcing markets, ride-pooling service is now becoming an important component of shared smart mobility. It is generally expected to improve vehicle utilization rate, and therefore alleviate traffic congestion and reduce carbon dioxide emissions. A few recent theoretical studies are cond...
Article
This paper studies how the advanced traveler information affects the stability of the day-to-day flow evolution of a transportation system. Two scenarios are investigated regarding the types of information provided, where one type is the historical travel time and the other the forecasted travel time. Given the information, travelers are assumed to...
Article
Travel time reliability plays an important role in travelers' route choice behaviors. Based on a previously developed generalized Bayesian traffic model, we propose different types of perceived knowledge (i.e., mean-variance-based type, relative gap-based type, and penalty-based type) to model travelers' daily route choice behavior concerning trave...
Article
With the rapid development of mobile-internet technologies, on-demand ride-sourcing services have become increasingly popular and largely reshaped the way people travel. Demand prediction is one of the most fundamental components in supply-demand management systems of ride-sourcing platforms. With an accurate short-term prediction for origin-destin...
Article
Ridesourcing platforms, such as Uber, Lyft and Didi, are now launching commercial on-demand ride-pooling programs that enable their affiliated drivers to serve two or more passengers in one ride. It is generally expected that successful designs of ride-pooling programs can reduce the required vehicle fleet size, and achieve various societally benef...
Preprint
Full-text available
Ride-hailing platforms generally provide various service options to customers, such as solo ride services, shared ride services, etc. It is generally expected that demands for different service modes are correlated, and the prediction of demand for one service mode can benefit from historical observations of demands for other service modes. Moreove...
Article
To improve the appeal of carsharing, we propose an integrated operation scheme of car-sharing and parking-sharing services, where a carsharing operator rents parking spaces from private owners to provide convenient parking options to carsharing users. We examine how the operator's profit and social welfare differ under the existing carsharing-only...
Preprint
Full-text available
To improve the appeal of carsharing, we propose an integrated operation scheme of carsharing and parking-sharing services, where a carsharing operator rents parking spaces from private owners to provide convenient parking options to carsharing users. We examine how the operator's profit and social welfare differ under the existing carsharing-only s...
Article
The bottleneck model introduced by Vickrey in 1969 has been recognized as a benchmark representation of the peak-period traffic congestion due to its ability to capture the essence of congestion dynamics in a simple and tractable way. This paper aims to provide a 50th anniversary review of the bottleneck model research since its inception. A biblio...
Preprint
Full-text available
Recently, some transportation service providers attempt to integrate the ride services offered by multiple independent ride-sourcing platforms, and passengers are able to request ride through such third-party integrators or connectors and receive service from any one of the platforms. This novel business model, termed as third-party platform-integr...
Article
On-demand ride services reshape urban transportation systems, human mobility, and travelers' mode choice behavior. Compared to the traditional street-hailing taxi, an on-demand ride services platform analyzes ride requests of passengers and coordinates real-time supply and demand with dynamic operational strategies in the ride-sourcing market. To t...
Article
This paper solves the problem of optimizing a surcharge-reward scheme and analyzes equilibrium properties incorporating commuters’ departure time choice to relieve crowding and queuing congestion in mass transit systems. The surcharge-reward scheme incentivizes commuters to switch departure times from a pre-specified central period to shoulder peri...
Article
This study models and manages the parking sharing problem in urban cities, where private parking owners can share their vacant spaces to parking users via a parking sharing platform. The proposed model takes into account the spatial dimension of parking, where clusters of curbside spaces and private shareable ones are distributed over different loc...
Article
A hybrid fare scheme (HFS) is proposed in this paper that combines a fare-reward scheme (H-FRS) and a non-rewarding uniform fare scheme (H-UFS) by considering the heterogeneity in transit commuters’ scheduling flexibility. It aims at reducing peak-hour congestion in the urban transit system with alternative options catering for various commuters. I...
Article
Full-text available
With the availability of the location information of drivers and passengers, ride-sourcing platforms can now provide increasingly efficient online matching compared with physical searching and meeting performed in the traditional taxi market. The matching time interval (the time interval over which waiting passengers and idle drivers are accumulate...
Article
Keywords: Public transit ridership Ridesplitting program Choice modeling First-mile and last-mile problem A B S T R A C T Public transit is an essential travel mode in many urban areas. Emerging dynamic ridesplitting programs provided by transportation network companies (TNCs) can be a double-edged sword to public transit. On the one hand, the prog...
Article
This study investigates the dynamical evolution of travelers' departure time choice in a bottleneck constrained roadway system with stochastic capacity. When considering day-today traffic evolution, this study explores two scenarios: travelers have long-term historical knowledge and real-time information provision; and travelers have short-term tra...
Article
Full-text available
We propose a dynamic tradable credit scheme for control of the day-to-day evolution process of traffic flows towards the system optimum (SO) state in a traffic network with elastic demand. In the scheme, the distribution and charge of travel credits are adjusted from period to period. The interacting dynamics among day-to-day traffic flows, period-...
Article
Full-text available
A hybrid fare scheme (HFS) is proposed in this paper that combines a fare-reward scheme (H-FRS) and a non-rewarding uniform fare scheme (H-UFS) by considering the heterogeneity in transit commuters’ scheduling flexibility. It aims at reducing peak-hour congestion in the urban transit system with alternative options catering for various commuters. I...
Conference Paper
This study models the parking sharing problem in a linear monocentric city, where private parking owners can share their vacant spaces to parking users via an e-platform, and then examines the platform operator's pricing strategies for revenue-maximization or social-cost-minimization. The model considers the spatial dimension of parking that both p...
Article
A smart design of transport systems involves efficient use and allocation of the limited urban road capacity in the multimodal environment. This paper intends to understand the system-wide effect of dividing the road space to the private and public transport modes and how the public transport service provider responds to the space changes. To this...
Article
This paper formulates and examines the passenger flow assignment (itinerary choice) problem in high-speed railway (HSR) systems with multiple-class users and multiple-class seats, given the train schedules and time-varying travel demand. In particular, we take into account advance booking cost of travelers in the itinerary choice problem. Rather th...
Article
This paper examines existing day-to-day models based on a virtual day-to-day route choice experiment using the latest mobile Internet technologies. With the realized day-to-day path flows and path travel times in the experiment, we calibrate several well-designed path-based day-to-day models that take the Wardrop's user equilibrium as (part of) the...
Article
Travel reliability can play an important role in shaping travelers’ route choice behavior. This paper develops a railway passenger assignment method to capture the reliability-based route choices, where the trains can have stochastic delays. The overall travel reliability has two components: the travel time reliability (of trains) and the associate...
Article
This paper has two major components. The first one is the day-today evolution of travelers' mode and route choices in a bi-modal transportation system where traffic information (predicted travel cost) is available to travelers. The second one is a public transit operator adjusting or adapting its service over time (from period to period) based on o...
Article
The rapid development of smartphone technology has led to the increased popularity of dynamic ridesharing apps used to organize ad hoc ridesharing trips between strangers on short notice. To support such real-time on-demand services, cost-sharing between drivers and riders is commonly centrally determined by ridesharing apps according to prescribed...
Article
This paper describes a new fare-reward scheme for managing a commuter’s departure time choice in a rail transit bottleneck, which aims to incentivize a shift in departure time to the shoulder periods of the peak hours to relieve queuing congestion at transit stations. A framework of the rail transit bottleneck is provided and the user equilibrium w...
Article
The dynamic traffic equilibrium problem has been a pivotal area of research in transportation for a few decades. The current state-of-the-art research in this area generally considers simultaneous departure time and route choice. In this paper, we theoretically prove that, in the simplest standard bottleneck model with a sufficient number of commut...
Article
Full-text available
This paper examines existing day-to-day models based on a virtual day-to-day route choice experiment using the latest mobile internet techniques. With the realized day-to-day path flows and path travel times in the experiment, we calibrate several well-designed path-based day-to-day models who take the Wardrop’s user equilibrium as (part of) their...
Article
Full-text available
We extend the proportional swap system by Smith (1984a) and the network tatonnement process by Friesz et al. (1994) to formulate the day-to-day evolution of departure time choice under bounded rationality in the bottleneck model. It is shown that the stationary points of the doubly dynamical systems exist and are equivalent to the boundedly rationa...
Article
We extend the proportional swap system by Smith (1984a) and the network tatonnement process by Friesz et al. (1994) to formulate the day-to-day evolution of departure time choice under bounded rationality in the bottleneck model. It is shown that the stationary points of the doubly dynamical systems exist and are equivalent to the boundedly rationa...
Article
Recent studies examined the households’ trip-timing decisions where adults have to drive their children to school. These studies focus on the cases where school is near workplace. However, different school locations can affect travels and activity patterns significantly. This study re-looks at the household shared-ride problem where school is near...
Article
Tradable credits have been recognized as a powerful instrument and are increasing used in many fields. This paper employs the tradable credits scheme on traffic mobility management and private provision of public transportation infrastructure through a novel kind of private financing of public road: build-equity-credit (BEC) scheme, hoping to achie...
Article
This paper proposes a route choice model that incorporates the various behavioral mechanisms in route choice proposed in the literature including the shortest path, bounded rationality, asymmetric preference, and the time surplus maximization. In the proposed model, travelers are assumed to compare travel cost to their status quo (travel cost of th...