The Role of Surge Pricing on a Service Platform with Self-Scheduling Capacity

Recent platforms, like Uber and Lyft, offer service to consumers via “self-scheduling” providers who decide for themselves how often to work. These platforms may charge consumers prices and pay providers wages that both adjust based on prevailing demand conditions. For example, Uber uses a “surge pricing” policy, which pays providers a fixed commission of its dynamic price. With a stylized model that yields analytical and numerical results, we study several pricing schemes that could be implemented on a service platform, including surge pricing. We find that the optimal contract substantially increases the platform’s profit relative to contracts that have a fixed price or fixed wage (or both), and although surge pricing is not optimal, it generally achieves nearly the optimal profit. Despite its merits for the platform, surge pricing has been criticized because of concerns for the welfare of providers and consumers. In our model, as labor becomes more expensive, providers and consumers are better off with surge pricing because providers are better utilized and consumers benefit both from lower prices during normal demand and expanded access to service during peak demand. We conclude, in contrast to popular criticism, that all stakeholders can benefit from the use of surge pricing on a platform with self-scheduling capacity

Analyzing the proposed reconfiguration of accident-and-emergency facilities in England

The Keogh Report of 2013 proposed a major reconfiguration of the accident and emergency (A&E) system under National Health Service (NHS) England to improve service. The proposed reconfiguration includes centralized facilities with multiple specialties as well as small local minor-injury facilities. We use stylized queuing models to analyze cost and service implications of the proposed reconfiguration. We find that increasing numbers of specialty patients that require admission to hospital makes splitting off specialty A&Es from general ones more attractive. The same applies for patients with minor injuries. Our work generally supports the reconfiguration recommended in the Keogh report but with some fine-tuning: For instance, a merger of A&Es (pooling) does not always make sense even though it increases patient numbers when the patients in the two A&Es are of different types. We provide simple quantitative rules to indicate whether the proposed reconfiguration could lower costs in any particular region of the country. The results here are consistent with some NHS England providers attempting specialty A&Es for geriatric patients and mobile drunkenness treatment centers on weekends. Our rules and approach can be useful for identifying candidate reconfiguration opportunities not only for NHS England but also for any other context where pooling and arrival heterogeneity are important considerations

Identification of unique reciprocal and non reciprocal cross packaging relationships between HIV-1, HIV-2 and SIV reveals an efficient SIV/HIV-2 lentiviral vector system with highly favourable features for in vivo testing and clinical usage.

BACKGROUND: Lentiviral vectors have shown immense promise as vehicles for gene delivery to non-dividing cells particularly to cells of the central nervous system (CNS). Improvements in the biosafety of viral vectors are paramount as lentiviral vectors move into human clinical trials. This study investigates the packaging relationship between gene transfer (vector) and Gag-Pol expression constructs of HIV-1, HIV-2 and SIV. Cross-packaged vectors expressing GFP were assessed for RNA packaging, viral vector titre and their ability to transduce rat primary glial cell cultures and human neural stem cells. RESULTS: HIV-1 Gag-Pol demonstrated the ability to cross package both HIV-2 and SIV gene transfer vectors. However both HIV-2 and SIV Gag-Pol showed a reduced ability to package HIV-1 vector RNA with no significant gene transfer to target cells. An unexpected packaging relationship was found to exist between HIV-2 and SIV with SIV Gag-Pol able to package HIV-2 vector RNA and transduce dividing SV2T cells and CNS cell cultures with an efficiency equivalent to the homologous HIV-1 vector however HIV-2 was unable to deliver SIV based vectors. CONCLUSION: This new non-reciprocal cross packaging relationship between SIV and HIV-2 provides a novel way of significantly increasing bio-safety with a reduced sequence homology between the HIV-2 gene transfer vector and the SIV Gag-Pol construct thus ensuring that vector RNA packaging is unidirectional.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Face validity of a proposed tool for staging canine osteoarthritis: Canine OsteoArthritis Staging Tool (COAST)

Abstract Osteoarthritis (OA) is a common, progressive degenerative disease of synovial joints. It can develop subsequent to an acquired disorder such as joint trauma but is primarily driven by developmental orthopedic disease in young dogs. Therefore, it is essentially characterised as an early onset but lifelong disease that worsens with age. Early intervention using a multi-modal drug and non-drug approach, with or without surgery as required, has the greatest potential for the most effective management of the disease. Timely implementation of a continuing care plan provides an opportunity to slow the rate of deterioration by reducing the negative impacts of OA-associated pain, encouraging appropriate levels of activity and improving strength and posture. Unfortunately, many dogs are presented to veterinary clinics only when marked behavioural changes are observed and substantial deterioration of the musculoskeletal and somatosensory systems has already occurred. To assist veterinarians with early and stage-specific diagnosis of OA in dogs, the authors present a proposed, practical diagnostic aid called 'COAST' (Canine OsteoArthritis Staging Tool) with face validity. As indicated by the successful implementation of staging systems for other companion animal diseases, it is expected that standardized staging of OA in dogs will help guide disease management plans and improve monitoring. The items used to construct COAST have been developed using consensus opinion of international experts from nine countries, who are actively working in the fields of small animal orthopaedics, anaesthesia and pain management. Further validation (test-retest, discriminatory ability, responsiveness, criterion validation) of the tool under field conditions is now required and the authors invite input

Sourcing Flexibility, Spot Trading, and Procurement Contract Structure

We analyze the structure and pricing of option contracts for an industrial good in the presence of spot trading. We combine the analysis of spot trading and buyers' disparate private valuations for different suppliers' products, and we jointly endogenize the determination of three major dimensions in contract design: (i) sales contracts versus options contracts, (ii) flat-price versus volume-dependent contracts, and (iii) volume discounts versus volume premia. We build a model in which a supplier of an industrial good transacts with a manufacturer who uses the supplier's product to produce an end good with an uncertain demand. We show that, consistent with industry observations, volume-dependent optimal sales contracts always demonstrate volume discounts (i.e., involve concave pricing). However, options are more complex agreements, and optimal option contracts can involve both volume discounts and volume premia. Three major contract structures commonly emerge in optimality. First, if the seller has a high discount rate relative to the buyer and the seller's production costs or the production capacity is low, the optimal contracts tend to be flat-price sales contracts. Second, when the seller has a relatively high discount rate compared to the buyer but production costs or production capacity are high, the optimal contracts are sales contracts with volume discounts. Third, if the buyer's discount rate is high relative to the seller's, then the optimal contracts tend to be volume-dependent options contracts and can involve both volume discounts and volume premia. However, when the seller's production capacity is sufficiently low, it is possible to observe flat-price option contracts. Furthermore, we provide links between production and spot market characteristics, contract design, and efficiency.National Science Foundation (U.S.) (contract CMMI-0758069)National Science Foundation (U.S.) (contract DMI-0245352

Coordination in closed-loop supply chain with price-dependent returns

This paper proposes two Closed-loop Supply Chain (CLSC) games in which a manufacturer sets some green activity programs efforts and a retailer sets the selling price. Both strategies influence the return rate, which is a state variable. The pricing strategy plays a key role in the identification of the best contract to achieve coordination as well as in achieving environmental objectives. The pricing strategy influences the return rate negatively, as consumers delay the return of their goods when the purchasing (and repurchasing) price is high. We then compare a wholesale price contract (WPC) and a revenue sharing contract (RSC) mechanism as both have interesting pricing policy implications. Our result shows that firms coordinate the CLSC through a (WPC) when the sharing parameter is too low while the negative effect of pricing on returns is too severe. In that case, the low sharing parameter deters the manufacturer to accept any sharing agreements. Further, firms coordinate the CLSC when the sharing parameter is medium independent of the negative impact of pricing on returns. When the sharing parameter is too high the retailer never opts for an RSC. We find that the magnitude of pricing effect on returns determines the contract to be adopted: For certain sharing parameter, firms prefer an RSC when the price effect on return is low and a WPC when this effect is high. In all other cases, firms do not have a consensus on the contract to be adopted and coordination is then not achieved

Estudio comparativo del rendimiento académico y la actividad física en dos institutos de enseñanza secundaria de Andalucía (España)

Objective: To assess whether there is some relationship between academic performance and physical condition, a study based on two schools with similar features. Methodology and Method: Quantitative experimental study, in which participated 144 pupils of both sexes and aged between 14 and 18 years who were in the 4th year of Obligatory Secondary Education (ESO). It was analyzed using standardized physical fitness test and have collected data on resistance (Cooper test), speed (50 meters sprint test), flexibility (test of deep trunk flexion) and abdominal strength (abs test for minute). Results and conclusion: There is a significant relationship between academic performance and physical activity of students in the data of resistance, speed and flexibility, although there is no significant relationship between academic performance and test Abs per minute.Objetivo: Valorar si existe alguna relación entre el rendimiento académico y la condición física en un estudio realizado en dos centros educativos con características similares. Material y Método: Estudio experimental cuantitativo, en el que han participado 144 alumnos de ambos sexos de edades comprendidas entre los 14 y los 18 años que cursan 4o curso de Enseñanza Secundaria Obligatoria (ESO). Se ha analizado la condición física mediante test estandarizados donde se han recogido datos referentes a la resistencia (test de Cooper), velocidad (test de 50 metros lisos), flexibilidad (test de flexión profunda de tronco) y fuerza abdominal (test de abdominales por minuto). Resultados y Conclusiones: Los resultados muestran una relación estadísticamente significativa entre el rendimiento académico y la actividad física de los alumnos en las pruebas de resistencia, velocidad y flexibilidad, aunque los mismos no han determinado relación significativa entre el rendimiento académico y la prueba de abdominales por minuto