539 research outputs found
Preference-aware task assignment in on-demand taxi dispatching: An online stable matching approach
A central issue in on-demand taxi dispatching platforms is task assignment, which designs matching policies among dynamically arrived drivers (workers) and passengers (tasks). Previous matching policies maximize the profit of the platform without considering the preferences of workers and tasks (e.g., workers may prefer high-rewarding tasks while tasks may prefer nearby workers). Such ignorance of preferences impairs user experience and will decrease the profit of the platform in the long run. To address this problem, we propose preference-aware task assignment using online stable matching. Specifically, we define a new model, Online Stable Matching under Known Identical Independent Distributions (OSM-KIID). It not only maximizes the expected total profits (OBJ-1), but also tries to satisfy the preferences among workers and tasks by minimizing the expected total number of blocking pairs (OBJ-2). The model also features a practical arrival assumption validated on real-world dataset. Furthermore, we present a linear program based online algorithm LP-ALG, which achieves an online ratio of at least 1−1/e on OBJ-1 and has at most 0.6·|E| blocking pairs expectedly, where |E| is the total number of edges in the compatible graph. We also show that a natural Greedy can have an arbitrarily bad performance on OBJ-1 while maintaining around 0.5·|E| blocking pairs. Evaluations on both synthetic and real datasets confirm our theoretical analysis and demonstrate that LP-ALG strictly dominates all the baselines on both objectives when tasks notably outnumber workers
A novel approach to independent taxi scheduling problem based on stable matching
This paper describes a taxi scheduling system, which aims to improve the overall efficiency of the system, both from the perspective of the drivers and the customers. This is of particular relevance to Chinese cities, where hailing a taxi on the street is by far the most common way in which taxis are requested, since the majority of taxi drivers operate independently, rather than working for a company. The mobile phone and GPS-based taxi scheduling system, which is described in this paper, aims to provide a decision support system for taxi drivers and facilitates direct information exchange between taxi drivers and passengers, while allowing drivers to remain independent. The taxi scheduling problem is considered to be a non-cooperative game between taxi drivers and a description of this problem is given. We adopt an efficient algorithm to discover a Nash equilibrium, such that each taxi driver and passenger cannot benefit from changing their assigned partner. Two computational examples are given to illustrate the effectiveness of the approach
Implementation Paper Modern and Smart Logistic Vehicle Using Tracking and Security
The logistic organization structure have climbed beginning late with the improvement of global positioning system (GPS), helpful correspondence movements, sensor and remote structures association advancements. The collaborations of the administrators system are fundamental as they can add to a few points of enthusiasm, for example, proposing right places for getting clients, developing pay of truck drivers, reducing holding up time, vehicle downpours and besides compelling fuel utilization and from this time forward broadening the measure of treks the drivers can perform. The rule motivation driving this structure would supply required vehicles that would be utilized to meet client requests through the arranging, control and utilization of the noteworthy headway and cutoff of related data and associations from beginning to objective. Customer brings to the table start to finish security to client and supplier information by utilizing QR code thought. Customer is proposition of closest best specialist relationship as shown by client intrigue and recognize spam master network. Joint efforts association suggests the commitment and association of plan and direct structures to control the improvement and land masterminding of foul materials, work-in-process, and completed inventories at the most unimportant all out expense. Composed endeavours solidifies the relationship of enthusiasm organizing, stock, transportation, and the mix of warehousing, materials managing, and packaging, all joined all through an arrangement of workplaces
Understanding Inequalities in Ride-Hailing Services Through Simulations
Despite the potential of online sharing economy platforms such as Uber, Lyft,
or Foodora to democratize the labor market, these services are often accused of
fostering unfair working conditions and low wages. These problems have been
recognized by researchers and regulators but the size and complexity of these
socio-technical systems, combined with the lack of transparency about
algorithmic practices, makes it difficult to understand system dynamics and
large-scale behavior. This paper combines approaches from complex systems and
algorithmic fairness to investigate the effect of algorithm design decisions on
wage inequality in ride-hailing markets. We first present a computational model
that includes conditions about locations of drivers and passengers, traffic,
the layout of the city, and the algorithm that matches requests with drivers.
We calibrate the model with parameters derived from empirical data. Our
simulations show that small changes in the system parameters can cause large
deviations in the income distributions of drivers, leading to a highly
unpredictable system which often distributes vastly different incomes to
identically performing drivers. As suggested by recent studies about feedback
loops in algorithmic systems, these initial income differences can result in
enforced and long-term wage gaps.Comment: Code for the simulation can be found at https://github.com/bokae/tax
Judicial Creation of Norms in Japanese Labor Law: Activism in the Service of — Stability?
This Article begins by examining the judiciary\u27s role in employment litigation. Part II then considers the implications of this and related examples of judicial creation of norms in Japan. Plainly, in this context the stereotype of a passive judiciary with little significance for private parties is inaccurate. Yet do these cases truly reflect judicial activism ? What is their significance with respect to the separation of powers debate? Even with regard to the sphere of private ordering, what judicial philosophy do they reflect? This Article then examines the impact that this judicially created set of employment norms has had, both on workers and employers, and considers future prospects for these norms within Japan. Finally, the closing section of this Article briefly considers some implications of the Japanese experience for the United States
Ambulance Emergency Response Optimization in Developing Countries
The lack of emergency medical transportation is viewed as the main barrier to
the access of emergency medical care in low and middle-income countries
(LMICs). In this paper, we present a robust optimization approach to optimize
both the location and routing of emergency response vehicles, accounting for
uncertainty in travel times and spatial demand characteristic of LMICs. We
traveled to Dhaka, Bangladesh, the sixth largest and third most densely
populated city in the world, to conduct field research resulting in the
collection of two unique datasets that inform our approach. This data is
leveraged to develop machine learning methodologies to estimate demand for
emergency medical services in a LMIC setting and to predict the travel time
between any two locations in the road network for different times of day and
days of the week. We combine our robust optimization and machine learning
frameworks with real data to provide an in-depth investigation into three
policy-related questions. First, we demonstrate that outpost locations
optimized for weekday rush hour lead to good performance for all times of day
and days of the week. Second, we find that significant improvements in
emergency response times can be achieved by re-locating a small number of
outposts and that the performance of the current system could be replicated
using only 30% of the resources. Lastly, we show that a fleet of small
motorcycle-based ambulances has the potential to significantly outperform
traditional ambulance vans. In particular, they are able to capture three times
more demand while reducing the median response time by 42% due to increased
routing flexibility offered by nimble vehicles on a larger road network. Our
results provide practical insights for emergency response optimization that can
be leveraged by hospital-based and private ambulance providers in Dhaka and
other urban centers in LMICs
Congestion effects of autonomous taxi fleets
Fleets of shared Autonomous Vehicles (AVs) could replace private cars by providing a taxi-like service but at a cost similar to driving a private car. On the one hand, large Autonomous Taxi (AT) fleets may result in increased road capacity and lower demand for parking spaces. On the other hand, an increase in vehicle trips is very likely, as travelling becomes more convenient and affordable, and additionally, ATs need to drive unoccupied between requests. This study evaluates the impact of a city-wide introduction of ATs on traffic congestion. The analysis is based on a multi-agent transport simulation (MATSim) of Berlin (Germany) and the neighbouring Brandenburg area. The central focus is on precise simulation of both real-time AT operation and mixed autonomous/conventional vehicle traffic flow. Different ratios of replacing private car trips with AT trips are used to estimate the possible effects at different stages of introducing such services. The obtained results suggest that large fleets operating in cities may have a positive effect on traffic if road capacity increases according to current predictions. ATs will practically eliminate traffic congestion, even in the city centre, despite the increase in traffic volume. However, given no flow capacity improvement, such services cannot be introduced on a large scale, since the induced additional traffic volume will intensify today’s congestion
Learning Riders\u27 Preferences in Ridesharing Platforms
Ridesharing platforms allow people to commute more efficiently. Ridesharing can be beneficial since it can reduce the travel expenses for individuals as well as decrease the overall traffic gridlocks. One of the key aspects of ridesharing platforms is for riders to find suitable partners to share the ride. Thus, the riders need to be matched to other riders/drivers. From the social perspective, a rider may prefer to share the ride with certain individuals as opposed to other riders. This leads to the rider having preferences over the other riders. A matching based on social welfare indicates the quality of the rides. Our goal is to maximize social welfare or the quality of rides for all riders. In order to match the riders, we need to know the preferences of the riders. However, the preferences are often unknown.
To tackle these situations, we introduce a ridesharing model that implements reinforcement learning algorithms to learn the utilities of the riders based on the riders\u27 previous experiences. We investigate a variety of measures for assessing social welfare, including utilitarian, egalitarian, Nash, and leximin social welfare. Additionally, we also compute the number of strong and weak blocking pairs in each socially optimal matching to compare the stability of these matchings. We provide a comparison between two reinforcement learning algorithms: ε-greedy and UCB1, for learning utilities of the riders, maximizing social welfare, and the number of blocking pairs in the socially optimal matching.
The ε-greedy algorithm with ε=0.1 provides the maximum accuracy in learning the utilities of the riders as compared to ε=0.0, ε=0.01, and UCB1 algorithm. It also provides a fewer number of blocking pairs suggesting more stability in the socially optimal matching than other reinforcement learning algorithms. However, the UCB1 algorithm outperforms all other reinforcement learning algorithms to provide maximum welfare in socially optimal matchings
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