Impact of uncertain demand and channel power on dual channel supply chain decisions

The paper aims to conduct an analysis of pricing strategies in a dual channel supply chain under external uncertainty, utilizing Interval numbers theory and Game theory as the theoretical basis. The focus is on maximizing the expected profits of manufacturers and retailers. Four models are considered: centralized decision-making, manufacturer's Stackelberg, retailer's Stackelberg strategy, and vertical Nash model, with the decision variable being the product price. By solving the game model, the paper compares the optimal decisions under the four models and conducts sensitivity analysis to reflect the influence of key parameters and analyze their relationships. The ultimate goal is to optimize profits under various circumstances by adjusting market potential and price parameters to determine the best price level. The findings suggest that decision-maker's risk indicators have a greater impact on decision results when market demand is less sensitive to price, and that the size of the market has a negative correlation with the impact of decision-maker's risk indicators on decision results.

Supply chain decision based on green investment subsidy and risk aversion

Considering the risk aversion characteristics of supply chain members, how to effectively design the government subsidy strategy and green supply chain strategy is a realistic and urgent issue. Regarding this, we optimize and compare four three-stage Stackelberg game models between government and a two-echelon green supply chain, namely both manufacturer and retailer risk neutral (BN), manufacturer risk aversion while retailer risk neutral (MA), retailer risk aversion while manufacturer risk neutral (RA) and both manufacturer and retailer risk aversion (BA). The government as the leader decides the subsidy rate of green input cost with the goal of maximizing social welfare; the manufacturer as the first follower makes decisions on product greenness and wholesale price to maximize its own interests; and the retailer as the second follower determines retail prices to maximize its own interests. Employing mathematical reasoning and numerical simulation investigate thoroughly the effects of the government subsidies and the members' risk aversion. Results indicate that an appropriate government subsidy investment has a positive effect on optimal decisions and related benefits. Risk aversion is in favor of improvement of product greenness and social welfare while reduction of retail price. With the increase of manufacturer risk aversion, green subsidy investment rate and retailer expected revenue increase; on the contrary, the wholesale price and manufacturer expected revenue decrease. With the increase of retailer risk aversion, the wholesale price and manufacturer expected revenue increase, while green subsidy investment rate and retailer expected revenue decrease. In the model of BN, product greenness and social welfare are the lowest, while retail price is the highest. BA is opposite to BN. In the model of RA, green subsidy investment rate and retailer expected revenue the lowest, while wholesale price and manufacturer expected revenue the highest. RA is opposite to MA. The government should formulate appropriate subsidy policies to encourage manufacturers to produce green products and raise consumers' green awareness. Enterprises should control their own risk aversion and assess the risk aversion of the other party reasonably.

Manufacturer invasion and online sales mode strategy considering the level of service quality

This study investigates the decision process of own-brand intrusion by contract manufacturers and their selection of invasion sales modes under the consideration of service quality disparities between brand manufacturers and contract manufacturers. Specifically, the study constructs a three-tier supply chain system comprising a brand manufacturer, a contract manufacturer, and an e-commerce platform. The equilibrium profits under different sales mode combinations are determined by using reverse induction methodology, and the optimal sales mode combinations are analyzed and compared. The study reveals that the decision process of contract manufacturers' own-brand invasion depends on the potential market demand. Furthermore, when brand manufacturers adopt the reselling mode, the service quality level does not affect the decision process of invasion sales modes. However, when brand manufacturers adopt the agency mode, contract manufacturers with low service quality levels are more suitable for invasion through the agency mode, whereas contract manufacturers with high service quality levels are better suited for invasion through the reselling mode. Additionally, for the equilibrium sales mode combination among members of the supply chain, it is observed that with lower commission rates, both brand manufacturers and contract manufacturers choose the agency mode, while with higher commission rates, both choose the reselling mode. When commission rates are moderate, brand manufacturers prefer the agency mode, whereas contract manufacturers prefer the reselling mode.

Modelling of pricing, crashing, and coordination strategies of prefabricated construction supply Chain with power structure

In the prefabricated construction industry, consumers are sensitive to the construction delivery time, and different power structures are very common. This research uses methods of Stackelberg game, Nash game and supply chain coordination, introduces a manufacturer crashing strategy into a prefabricated construction supply chain and investigates the assembler pricing, manufacturer crashing, and supply chain coordination strategies under three different power structures. It finds that adopting a crashing strategy improves the supply chain's profit, while the dynamic wholesale price contract achieves supply chain coordination. Meanwhile, when consumer time and price sensitivity are low, it is easier to achieve high profits in the supply chain under unequal power distribution. Conversely, the supply chain profit is higher in the case of a Nash game. This study innovatively introduces the thought of power structure and crashing strategy into the prefabricated construction supply chain, and provides the optimal price and delivery time under three different power structures for prefabricated construction enterprises and realizes supply chain coordination. The conclusion can provide decision suggestions for the prefabricated construction enterprises under different competitive environments.

Optimal decisions on price and inventory for a newsboy-type retailer with identifiable information and discount promotion

Consider a retailer selling a seasonal item, new items are stocked at the beginning of sale season and no inventory replenishment is permitted. Assuming the initial price is exogenous and the information about demand becomes more accurate as the sales season progresses, the retailer is allowed to make an in-season price adjustment after conducting a review. After the review time, if the price is adjusted to be lower than the initial price, demand increases more quickly with price decreasing which reflects the promotional effect of discount. Given the initial inventory, an optimal price adjusting model is proposed to maximize the retailer's revenue. Taking decisions on inventory into account, the proposed model is extended to maximize the retailer's profit rather than revenue. Numerical examples are also illustrated to test the proposed model. The results show that the optimal in-season price mainly depends on the proportion of the remaining demand, the price sensitivity, and the effect of sales promotion. An important managerial implication is that the retailer should gather the demand information about the price and raise the in-season price as soon as possible to gain more revenue when the price elasticity is small enough. Otherwise, when the price elasticity is larger, the retailer should maintain or decrease the price to gain more revenue.

An analysis of strategies for adopting blockchain in green supply chains under corporate social responsibility

In recent years, green products have received increasing attention by firms and consumers, but consumers often have uncertainty about the green degree of products. Many firms adopt blockchain technology to solve this problem, but blockchain adoption will bring privacy concerns to consumers. Meanwhile, corporate social responsibility has become one of the hot topics concerned by firms. Based on this, a Stackelberg game model dominated by the manufacturer is constructed to study the strategies of blockchain adoption for green supply chains under corporate social responsibility. The interaction of corporate social responsibility awareness and blockchain adoption in different models is verified through the calculation and simulation analysis of the optimal decision of the supply chain members. The research results show that no matter whether supply chain members have corporate social responsibility awareness, the manufacturer should adopt blockchain technology only when the privacy cost of consumers is low. After blockchain technology is adopted, the profit and utility of retailer, the manufacturer's utility, consumer surplus, and social welfare will be higher. However, when the manufacturer has corporate social responsibility awareness, the manufacturer's profit may be damaged by blockchain adoption. In addition, when supply chain members have corporate social responsibility awareness, the manufacturer is more likely to adopt blockchain technology. And with the enhancement of corporate social responsibility awareness, blockchain technology is more likely to be adopted. It provides a reference for the blockchain adoption strategies of the green supply chain under corporate social responsibility.

Effectiveness of price limits: Evidence from China's ChiNext market

Starting from August 24, 2020, the daily stock price limits in China's ChiNext market have been adjusted from 10% to 20%. We use this reform to study the effectiveness of price limits in China's stock market. We test four hypotheses about price limits: delayed price discovery, volatility spillover, trading interference, and magnet effect. Using the event study method, we examine the differences in the behavior of stock price, trading volume, and volatility before and after the reform. We confirm the delayed price discovery, volatility spillover and trading interference hypothesis of price limits, and find that these negative effects of price limits are more serious when lower limits are hit. In addition, we examine the distribution of large price movements before and after the reform and find no evidence of the magnet effect of price limits. The present research has important implications for policymakers and investors in China's stock market.

Effects of COVID-19 outbreak in pricing and collaboration of a health-social dual-channel supply chain

The coronavirus pandemic has affected most aspects of product supply and consumer behaviors and led to transformations in the supply chain. The COVID-19 pandemic and the requirements to reduce its prevalence have led many people to shop online and encouraged many manufacturers to sell their products online. In this study, a manufacturer, who intends to possess an online sales channel, and a retailer, who has an in-person sales channel, are considered. Then, pricing strategies and collaboration mechanisms between them in the health-social dual-channel supply chain are investigated. This study is developed in three models, including centralized, decentralized, and collaborated under Stackelberg game, whereas the optimal price of products in each channel, level of implementation of health and safety protocols in retailers, advertising level, and status of online shopping performance are obtained for improving customer trust. Moreover, the demand is represented as a function of selling prices of products in online and in-person shops, compliance level of health protocols, level of online shopping performance, and advertising in health during the COVID-19 pandemic. Although the centralized model provides more profit for the manufacturer, the collaborated model provides the highest profit for the retailer. Thus, since the supply chain profit of centralized and collaborated models is close, the collaboration model is the best option for members in this situation. Sensitivity analysis is finally performed to evaluate the impact of key parameters, and then according to obtained results, some management insights are suggested for the dual-channel supply chain during the COVID-19 pandemic.

Does Environmental Education Always Contribute to Remanufacturing Supply Chain Development?

Remanufacturing, as an effective way to save resources and alleviate environmental pollution, has gradually become a sustainable practice. Environmental education contributes to the development of remanufacturing by increasing the number of consumers willing to purchase remanufactured products (RPs). However, the incumbent manufacturer usually has limited remanufacturing capability together with yield uncertainty, making a third-party remanufacturer (3PR) an alternate channel choice. This study develops an analytical model to examine the effects of environmental education on a retailer's choice of remanufacturing channels under in-store competition. Results show that consumer environmental education has the potential to significantly improve the retailer and supply chain profits, and temperate environmental education is always desirable for 3PR. The introduction of 3PR benefits the consumer when the retailer's remanufacturing technology level is low. Furthermore, when the environmental impact of defective RPs is relatively high, and environmental education is temperate, selecting a 3PR will enhance environmental sustainability. This study also shows that 3PR can help achieve a win-win situation when environmental education and consumer acceptance of RPs are both in a certain range.

Coordinating a three-level contract farming supply chain with option contracts considering risk-averse farmer and retailer

We considered a three-level contract farming supply chain comprising a risk-averse farmer, a risk-neutral supplier, and a risk-averse retailer. The farmer plants and grows fresh agricultural products with yield uncertainty, the supplier is the leader of the supply chain and the designer of the contracts, and the retailer sells processed products with random demand. Under CVaR criterion, this paper discusses three option contracts between the supplier and the retailer, as well as wholesale price contracts or replenishment cost-sharing contracts between the supplier and the farmer. Results show that when the farmer is risk-neutral, option contracts with or without replenishment cost-sharing contracts can maximize the total profit and increase the profits of all members simultaneously. When the farmer and the retailer are risk-averse, only option contracts with replenishment cost-sharing contracts can ensure supply chain full coordination and Pareto improvement by adjusting the option parameters and making the farmer's sharing ratio equal to his risk aversion coefficient. Moreover, through numerical analysis, we discovered that the interval of the Pareto improvement decreases with the retailer's risk aversion coefficient and the quantity loss rate, and increases with the farmer's risk aversion coefficient. The supplier will not be able to increase his own profits when the loss rate is excessively large. Therefore, the leader should consider the risk aversion degree of all parties and the quantity loss rate of fresh agricultural products before choosing contracts.

The impact of cross-shareholding under different power structures considering green investment and green marketing

Cross-shareholding has played an important role in strengthening strategic synergy among enterprises, but its impact on the green development of enterprises is unclear. In this paper, we construct an analytical framework that includes a manufacturer and a retailer to explore the impact of cross-shareholdings under different leaderships on green supply chain operational decisions and profits, in which the manufacturer invests in green technologies and the retailer conducts green marketing. By constructing and solving the game model of manufacturer-led and retailer-led before and after cross-shareholding, it is found that after cross-shareholding, the product's green level and the retailers' marketing level are improved. For supply chain leaders, cross-shareholdings always increase their profits. Only when the follower holds the leader's shares no more than a certain value, cross-shareholding will increase the total profit of the supply chain. In addition, we obtain the optimal decisions and profits of the supply chain in the integrated situation and design two-part pricing contracts to achieve cross-shareholding supply chain coordination. The results of this paper can provide theoretical guidance and decision support for enterprises interested in using cross-shareholding to improve supply chain performance.

Research the effect of anticipated regret and fairness concerns on retailer-led supply chain

Considering the consumer's anticipated regret caused by price discount, the impact of anticipated regret and manufacturers' fairness concerns on pricing and profits is explored, and a revenue-sharing contract to optimize the profits of supply chain is explored. In centralized decision-making model with manufacturer's fairness neutrality and retailer-led decentralized decision-making model with the manufacturer's fairness concerns, numerical simulation and model comparison is used to analyse regret sensitivity coefficient, consumer heterogeneity, the fairness concern coefficient on pricing decisions and profit coordination. Our results reveal that consumer's anticipated regret has a negative impact on product prices, retailer's profit and manufacturer's profit. Manufacturer's fairness concerns also increase product price and reduce profits of all parties. Retailer-led supply chain can share the revenue to achieve Pareto optimization. When formulating promotional strategies, retailers should consider the characteristics of anticipated regrets of consumers.

Pricing Policies of Green Dual-Channel Supply Chain with Fairness Concerns and Altruistic Preferences Based on Consumers' Environmental Awareness and Channel Preference

Taking into consideration fairness concerns and altruistic preferences of manufacturers, this paper aims to propose a green dual-channel supply chain that incorporates consumers' environmental awareness (CEA) and channel preference. The purpose of this work is to explore and further compare the optimal outcomes in a green dual-channel supply chain in three scenarios, which are the fairness-neutrality scenario (Model N), the manufacturer is concerned with fairness scenario (Model F), and the manufacturer has altruistic preference (Model A), respectively. The game-theoretical models with different fairness preferences, comparative, and numerical analyses are used to put forward the impacts of consumers' channel preference and CEA on pricing, profits, and utilities, and to identify the differences in decisional outcomes between the three models. The results indicate that CEA always contributes to developing the green market while adversely affecting common products. Moreover, consumers' channel preferences might enable the manufacturer and retailer to enhance profitability under certain conditions. The findings also reveal that manufacturer's fairness concerns can possibly increase the demand for green products but impair the overall performance of the supply chain in general. Moreover, while the manufacturer's altruistic preference benefits the retailer's profits, it has a detrimental effect on the performance of the green supply chain. The practical implications of this research come to promote green consumption and increasing consumer awareness of environmental protection are effective ways to develop a green supply chain. It is also important to note that in order to maintain the durability and stability of the sup-ply chain, the manufacturer must maintain a moderate level of fairness preference behaviors so that downstream retailers will remain enthusiastic about establishing long-term relationships.

A Randomized Controlled Trial of a Research-Tested Mobile Produce Market Model Designed to Improve Diet in Under-Resourced Communities: Rationale and Design for the Veggie Van Study

Mobile produce markets are increasingly popular retail vendors used for providing access to fresh fruits and vegetables (F&V) in under-resourced communities; however, evaluation is limited due to design and implementation challenges. This protocol presents the original design of a randomized control trial aimed at assessing the effectiveness of the evidence-based Veggie Van (VV) mobile market model. Nine US community partner organizations were asked to partner with four community sites serving lower-income areas. Sites are randomized to either intervention or control. Intervention sites will host a mobile market for one year while the control sites will host planning events, with the goal to open a market afterward. Eligible participants are aged ≥ 18, the primary household shopper, live nearby/regularly frequent the site, and have expressed interest in learning about a mobile market. The primary outcome, F&V consumption, will be assessed via dietary recall at baseline and 12 months and compared between the intervention and control sites. This research advances work on the VV model and methods for mobile market evaluation with the addition of more robust measures and the study design. Determining the effectiveness of the VV model is imperative to justify taking it to scale to enhance the impact of mobile markets.

Effect of lean manufacturing tools on sustainability: the case of Mexican maquiladoras

The Mexican maquiladora industry is applying Lean Manufacturing Tools (LMT) in its production lines; however, few studies have investigated its relationship with sustainability (social, economic, and environmental). This paper presents a second-order structural equation model (SEM) relating 8 LMT integrated into three independent latent variables: continuous improvement (Kaizen and Gemba), supporting tools (Andon, visual management, and Poka-yoke), and machinery and equipment (total productive maintenance, overall equipment effectiveness, and Jidoka) that are related to social, economic, and environmental sustainability as dependent variables. The model is validated with information obtained from 249 companies using partial least squares. Findings show that the application of LMT in the Mexican maquiladora industry avoids the generation of waste and reprocessing. Likewise, the improvement of production processes reduces the waste emitted into the environment and reduces energy consumption. Also, when companies have environmental programs, the work environment is safe, and labor relations are improved, increasing morale and the commitment to work for the company, gaining economic and ecological benefits.

Global cropland could be almost halved: Assessment of land saving potentials under different strategies and implications for agricultural markets

The pressure on land resources continuously increases not only with the rising demand for agricultural commodities, but also with the growing need for action on global challenges, such as biodiversity loss or climate change, where land plays a crucial role. Land saving as a strategy, where agricultural productivity is increased to allow a reduction of required cropland while sustaining production volumes and meeting demand, could address this trade-off. With our interdisciplinary model-based study, we globally assess regional potentials of land saving and analyze resulting effects on agricultural production, prices and trade. Thereby, different land saving strategies are investigated that (1) minimize required cropland (2) minimize spatial marginalization induced by land saving and (3) maximize the attainable profit. We find that current cropland requirements could be reduced between 37% and 48%, depending on the applied land saving strategy. The generally more efficient use of land would cause crop prices to fall in all regions, but also trigger an increase in global agricultural production of 2.8%. While largest land saving potentials occur in regions with high yield gaps, the impacts on prices and production are strongest in highly populated regions with already high pressure on land. Global crop prices and trade affect regional impacts of land saving on agricultural markets and can displace effects to spatially distant regions. Our results point out the importance of investigating the potentials and effects of land saving in the context of global markets within an integrative, global framework. The resulting land saving potentials can moreover reframe debates on global potentials for afforestation and carbon sequestration, as well as on how to reconcile agricultural production and biodiversity conservation and thus contribute to approaching central goals of the 21st century, addressed for example in the Sustainable Development Goals, the Paris Agreement or the post-2020 global biodiversity framework.

Strategic interaction of original equipment manufacturers between outsourcing and purchasing in a quality-differentiated market

Economic globalization has swept the whole world. To focus on their main business, enterprises that are referred to as original equipment manufacturers (OEMs) outsource non-core production activities to contract manufacturers (CMs). By constructing a two-level supply chain consisting of two competing OEMs and one upstream CM, the strategic interaction of the OEMs between outsourcing and purchasing is studied. Specifically, the CM can offer custom- and predefined modes of original equipment manufacturing (namely, CO mode and PO mode, respectively). The former mode enables OEMs to determine product quality, while the latter only allows them to purchase from several quality configurations. The results show that, first, since the CO mode allows the adopter to lead the product design, whether to choose this mode depends on the required R&D cost. Interestingly, however, a lower R&D cost does not necessarily result in the adoption of the CO mode if the product quality difference is small under the PO mode. Second, the optimal purchasing strategy of an OEM is indifferent to the outsourcing mode (CO and PO) of its rival but significantly affected by the quality cost. However, compared to the PO mode, choosing the CO mode would cause the competitor to suffer more profit losses. Third, differing from the prior literature, this paper finds that when the downstream OEM can make quality decisions, although this may lead to profit loss of the contract manufacturer in some channels, it could benefit the CM overall.

Factors Influencing Implementation, Sustainability and Scalability of Healthy Food Retail Interventions: A Systematic Review of Reviews

The aim of this systematic review of reviews was to synthesise the evidence on factors influencing the implementation, sustainability and scalability of food retail interventions to improve the healthiness of food purchased by consumers. A search strategy to identify reviews published up until June 2020 was applied to four databases. The Risk of Bias in Systematic Review tool was used. Review findings were synthesised narratively using the socio-ecological model. A total of 25 reviews met the inclusion criteria. A number of factors influenced implementation; these included retailers' and consumers' knowledge and preferences regarding healthy food; establishing trust and relationships; perceived consumer demand for healthy food; profitability; store infrastructure; organizational support, including resources; and enabling policies that promote health. Few reviews reported on factors influencing sustainability or scalability of the interventions. While there is a large and rapidly growing body of evidence on factors influencing implementation of interventions, more work is needed to identify factors associated with their sustainability and scalability. These findings can be used to develop implementation strategies that consider the multiple levels of influence (individual, intrapersonal and environmental) to better support implementation of healthy food retail interventions.

Factors stimulating value micro-businesses attribute to digital marketing technology (DMT) adoption

Most micro-business managers in Nigeria do not see the adoption of digital marketing technology (DMT) as vital for business. Many consider it as a precondition to support managerial or operational activities, not as a tactical and/or strategic tool. Although most studies focused on large organisations, the outcome of such research may not be appropriate to micro-businesses. This is informed by the negligence of micro-businesses’ idiosyncrasies and their thought of digitalization as a precondition for managerial activities without considering the value small businesses attached to these devices in terms of aiding the use as strategic tools. This renders micro-businesses’ digitalization an under-reflected phenomenon. Yet, studies spend less on examining the factors that specifically stimulate the value micro-businesses attach to these applications, leading to constant adoption and usage. Hence, there is a need for a thorough exploration of the factors that shape the value of digital marketing applications in micro-businesses in Nigeria. The study is qualitative in nature and interviews (unstructured and semi-structured) were carried out with 26 micro-businesses which was drawn purposefully from the online database and underpinned by Technology, Organisation and Environment (TOE) framework. The study revealed eleven (11) critical success factors stimulating value micro-businesses attribute to digital marketing technology (DMT) adoption. These factors include long-term functional capacity, integration capacity, expansion capacity which are related to technology context. Collective capability, collaborative experience are linked to the organisation context while adaptive training, service delivery, customer fulfilment are linked to environmental context. The study also unveiled expectancy context which is linked to budget, growth and profitability and aid in the extension of the TOE framework. This study will be of importance to academics and practitioners because it provides further awareness into DMT adoption framework, factors critical to the DMT adoption and may assist in reducing the number of resources spent in search of information aimed at helping DMT adoption by micro-businesses.

Construction and optimization of inventory management system via cloud-edge collaborative computing in supply chain environment in the Internet of Things era

The present work aims to strengthen the core competitiveness of industrial enterprises in the supply chain environment, and enhance the efficiency of inventory management and the utilization rate of inventory resources. First, an analysis is performed on the supply and demand relationship between suppliers and manufacturers in the supply chain environment and the production mode of intelligent plant based on cloud manufacturing. It is found that the efficient management of spare parts inventory can effectively reduce costs and improve service levels. On this basis, different prediction methods are proposed for different data types of spare parts demand, which are all verified. Finally, the inventory management system based on cloud-edge collaborative computing is constructed, and the genetic algorithm is selected as a comparison to validate the performance of the system reported here. The experimental results indicate that prediction method based on weighted summation of eigenvalues and fitting proposed here has the smallest error and the best fitting effect in the demand prediction of machine spare parts, and the minimum error after fitting is only 2.2%. Besides, the spare parts demand prediction method can well complete the prediction in the face of three different types of time series of spare parts demand data, and the relative error of prediction is maintained at about 10%. This prediction system can meet the basic requirements of spare parts demand prediction and achieve higher prediction accuracy than the periodic prediction method. Moreover, the inventory management system based on cloud-edge collaborative computing has shorter processing time, higher efficiency, better stability, and better overall performance than genetic algorithm. The research results provide reference and ideas for the application of edge computing in inventory management, which have certain reference significance and application value.

Facilitators and barriers to physicians' entrepreneurial ventures in major Japanese cities: A qualitative study

BACKGROUND

The Japanese healthcare system currently faces numerous challenges, including a super-aging society and an excessive burden on medical workers; therefore, the need for innovative solutions from healthcare ventures to tackle these issues has increased. Meanwhile, as physicians play important roles in healthcare ventures, the need for Japanese physician entrepreneurs is more important than ever. Given the lack of research examining barriers to physicians starting ventures and what skills, knowledge, and surrounding environments act as facilitators, this study aimed to identify the facilitators and barriers faced by physicians to start ventures.

METHODS

Between September and November 2019 and in May 2021, qualitative interviews were conducted with 33 participants, which included eight physician entrepreneurs; two administrative officers at the Ministry of Health, Labour and Welfare and the Ministry of Economy, Trade and Industry; three faculty members at Tokyo Medical and Dental University (in-depth interviews); and 20 medical students (focus group discussions). The interviews were deductively coded based on the social ecological model. The inductive approach was applied to coding any knowledge necessary to start a business. We conducted member checking with three physician entrepreneurs and seven medical students to improve our results' credibility.

RESULTS

The factors influencing a physician's decision to launch a new business include their willingness to contribute to society, the unique environment in which an individual is placed while in medical school and afterward, negative aspects of the lack of diversity in physicians' careers, the financial stability provided by a medical license, and self-efficacy.

CONCLUSIONS

Our study revealed facilitators and barriers to physicians' entrepreneurial ventures. Knowledge about these factors might be useful in supporting physicians to launch or become involved in healthcare ventures.

Digital Food Retail: Public Health Opportunities

For over two decades, digital food retail services have been emerging alongside advances in mobile technology and improved access to wi-fi. Digitalization has driven changes within the food environment, complicating an already complex system that influences food-related behaviors and eating practices. Digital food retail services support an infrastructure that enhances commercial food systems by extending access to and availability of highly processed foods, further escalating poor dietary intakes. However, digital food retail services are heterogeneous–food delivery apps, online groceries, and meal kits–and can be feasibly adapted to nutrition interventions and personalized to individual needs. Although sparse, new evidence indicates great potential for digital food retail services to address food insecurity in urban areas and to support healthy eating by making it easier to select, plan, and prepare meals. Digital food retail services are a product of the digital transformation that reflect consumers’ constant need for convenience, which must be addressed in future research and interventions. This paper will discuss public health opportunities that are emerging from the global uptake of digital food retail services, with a focus on online groceries, food delivery apps, and meal kits.

Trade vulnerability assessment in the grain-importing countries: A case study of China

Since the 2008 global food crisis, food security vulnerability has been a prominent topic in the food policy debate. However, vulnerability is inherently difficult to conceptualize and is more challenging to operationalize and measure. This study constructs a mathematical model and takes China as a case study to measure the vulnerability and sensitivity of China with its partners in the international grain trade. The results show that 1) the degree of interdependence between China and its grain trading partners is asymmetric, which generates trade vulnerability or economic power; 2) the vulnerability of China’s food trade shows a high spatiotemporal heterogeneity among countries: the higher vulnerability zones are concentrated in North America and Northeast Asia, and the scope of the higher vulnerability zones tends to expand; 3) Our results also reveal that China also has different sensitivities to fluctuations in grain markets from different countries, and the higher sensitive zones of the grain trade in China are mainly distributed in America, Europe, and Oceania. The main contribution of this paper is the development of a methodology for food trade vulnerability assessment and examines the influence of international food trade on food security in importing countries, measured using the vulnerability index and sensitivity index. Nevertheless, the conclusions of this study can be considered preliminary, and there remains great potential for future studies to deepen and broaden our analyses further.

Recommending blue ocean technologies for subcontractors: A framework based on business reports of prime contractors and patents

Subcontractors depend heavily on their prime contractor and thus find it very risky to enter a new business on their own. This study proposes a framework for these subcontractors to develop blue ocean technologies related to their prime contractor. First, the primary technologies predicted to be promising are extracted from the business reports of the prime contractor. Sub-technologies are then selected through a patent-based search using keywords and International Patent Classification codes of the primary technologies. From them, blue ocean technologies are proposed by optimizing the weighted mean of the min-max normalized market value, degree of competition in the technology market, and subcontractors' potential technological capabilities for each sub-technology. This study shows that subcontractors can enhance their technology competitiveness by finding a low-risk blue ocean technology. Our empirical research on the subcontractors of a semiconductor firm identified technological patent fields for them to pursue. From our framework, subcontractors can identify blue ocean technologies by considering their prime contractor's future industrial areas and technologies of interest as well as their own technological capabilities. Furthermore, the prime contractors can gain the synergy effect of technology expansion through cooperation.

Production planning of a furniture manufacturing company with random demand and production capacity using stochastic programming

In this article two multi-stage stochastic linear programming models are developed, one applying the stochastic programming solver integrated by Lingo 17.0 optimization software that utilizes an approximation using an identical conditional sampling and Latin-hyper-square techniques to reduce the sample variance, associating the probability distributions to normal distributions with defined mean and standard deviation; and a second proposed model with a discrete distribution with 3 values and their respective probabilities of occurrence. In both cases, a scenario tree is generated. The models developed are applied to an aggregate production plan (APP) for a furniture manufacturing company located in the state of Hidalgo, Mexico, which has important clients throughout the country. Production capacity and demand are defined as random variables of the model. The main purpose of this research is to determine a feasible solution to the aggregate production plan in a reasonable computational time. The developed models were compared and analyzed. Moreover, this work was complemented with a sensitivity analysis; varying the percentage of service level, also, varying the stochastic parameters (mean and standard deviation) to test how these variations impact in the solution and decision variables.

Coordination of a fresh agricultural product supply chain with option contract under cost and loss disruptions

This paper analyzes the option coordination problem of a fresh agricultural product supply chain under two supply chain structures, when the production cost and the loss rate are disrupted simultaneously. This paper provides the explicit option coordination conditions for the disrupted supply chain under two supply chain structures, and then explores the effects of the disruptions and supply chain structure on the option coordination conditions. The results suggest that it is unfavorable to apply the original coordinating contracts without disruptions to coordinate the disrupted supply chain. The coordination of the disrupted supply chain can be achieved with knowledge of the distribution of demand. In two coordinating contracts for the disrupted supply chain, the exercise price is still at the original level without disruptions while the option price deviates from the original level without disruptions. Moreover, the relationships of the coordination conditions in two supply chain structures depend on the value of the profit allocation coefficient. When the profit allocation coefficient exceeds (falls behind) a certain threshold, the option price is set at a higher (lower) value in the supplier-led supply chain structure than in the distributor-led supply chain structure, while the exercise price is set at a lower (higher) value in the supplier-led supply chain structure than in the distributor-led supply chain structure. Finally, the disrupted supply chain with any supply chain structure will perform better in the modified coordinating contracts than in the original coordinating contracts without disruptions.

Simulations of scenarios for urban household water and energy consumption

The expansion of cities and their impacts currently constitutes a challenge for the achievement of sustainable development goals (SDGs). In this respect, assessments of resource consumption and the delivery of appropriate policies to support resource conservation are of paramount importance. Previous works in the literature have focused on one specific resource (e.g., water, energy, food) at the household level, while others have analysed the inter-relations among different resources (i.e., the nexus approach) at larger spatial scales (e.g., urban level). Moreover, household behavioural attitudes are generally excluded while assessing resource consumption scenarios. This work overcomes previous limitations by proposing a causal-loop structure derived from the literature, from which simulations of different scenarios can be generated that consider the nexus between food, energy and water at the household level. These simulations can provide alternative scenarios to assess the impacts of monetary policies as well as education and communication actions on the enhancement of resource savings and consider both their current use and household preferences. The metropolitan area of Napoli was chosen as the testbed area for the simulations. The results, in relation to the testbed, proved that communication actions would be most appropriate to increase the level of resource savings. The business-as-usual scenario was especially sensitive to variations in individual preferences towards pro-environmental behaviours and showed their higher impacts on the results. Improvements of this method and its derived scenarios in the context of the urban planning process could support the implementation of informed policies towards the conservation of key resources and promotion of sustainable citizen behaviour.

Evaluation and spatial agglomeration analysis of the green competitiveness of China's manufacturing industry at the provincial level

The pressures to maintain a low-carbon economy makes green competitiveness (GC) a significant issue in China. It has been found that the development of Internet and E-commerce contributes significantly to GC of regional economy, yet there are still lack of quantitative investigation on their effects, which can be used to further guide the economic development. Therefore, this study constructs a new evaluation index for the green competitiveness of the regional manufacturing industry in China by introducing Internet application indicators and E-commerce development indexes into its evaluation system. The results show Jiangxi and Gansu moved upward significantly in the GC ranking over the period. The development of the Internet and E-commerce has the most significant impact on GC of regional manufacturing. The lack of green manufacturing capabilities and green innovation drivers led to a decline in the GC ranking of Liaoning, Tianjin, Guangxi and Heilongjiang. Finally, this study uses Moran’s I index to investigate the spatial agglomeration effect of the green development of the manufacturing industry at the province level. The results show an increase in the GC of China’s regional manufacturing industry, and the GC of manufacturing industry shows a significant agglomeration effect. Based on the above conclusions, the proposal to promote the balanced development of the GC of the manufacturing industry is proposed.

Influencing factor modeled examination on internet rural logistics talent innovation mechanism based on fuzzy comprehensive evaluation method

In recent years, China’s economic development has advanced by leaps and bounds, but the development of China’s rural logistics system is still at its primary stage. Some remote areas with inconvenient transportation are still in a state of serious lack or even blank, and due to the high cost of rural logistics delivery services, the rural logistics business of the enterprise also has a profit problem, which limits the development of rural logistics talent innovation to some extent. The purpose of this paper is to study a new influencing factor model of the Internet rural logistics talent innovation mechanism. This paper innovatively proposes countermeasures to improve the innovation of e-commerce practitioners in rural areas. Through research, the author finds that the innovation of rural e-commerce application talents in China is generally low. The key point of the solution lies in how to improve the level of innovation in rural e-commerce application talents. According to the status quo, identify the factors that hinder the innovation and improvement of rural e-commerce application talents. Combined with the great environment of the development of rural e-commerce industry in China, the paper proposes to improve the countermeasures for improving the innovation of rural e-commerce application talents. Improve the current situation of rural e-commerce application talents mediocrity and promote the innovation of rural e-commerce application talents. Fundamentally promote agricultural development and the building of a new socialist countryside. This paper adopts the literature research method based on fuzzy comprehensive evaluation method, system analysis method and the combination of questionnaire survey and interview. Through big data and information science methods for data processing, using a company’s Internet rural talent data set to simulate, the results It shows that with the method of this paper, the recognition rate reaches 98%, the speed increases obviously, and it is 20% faster than others.

Assessing the application of big data technology in platform business model: A hierarchical framework

This research aims to create a hierarchical framework for the development of a platform business model based on big data. However, this hierarchical framework must consider unnecessary attributes and the interrelationships between the aspects and the criteria. Hence, fuzzy set theory is used for screening out the unnecessary attributes, a decision-making and trial evaluation laboratory (DEMATEL) is proposed to manage the complex interrelationships among the aspects and attributes, and interpretive structural modeling (ISM) is used to divide the hierarchy and finally construct a hierarchical framework. The results reveal that (1) value proposition and community building in value production are fundamental links; (2) information technology and information management in value production are technical supports; (3) customer development in value marketing is the power source; and (4) value acquisition is the last link, which is established on the basis of and influenced by value marketing and value network. This hierarchical framework aims to guide the platform toward the application of big data. This study also proposes engagement of stakeholders for promoting value creation and establishing a sound business model from multiple levels and links.

To buy or not buy food online: The impact of the COVID-19 epidemic on the adoption of e-commerce in China

Drawing on a recent online survey combined with city-level data, this paper examines the impact of the COVID-19 on consumers' online food purchase behavior in the short term. To address the potential endogeneity issues, we adopt an instrumental variable (IV) strategy, using the distance from the surveyed city to Wuhan as the instrumental variable. We show that our IV method is effective in minimizing potential bias. It is found that the share of confirmed COVID-19 cases increases the possibility of consumers purchasing food online. This is more likely to be the case for young people having a lower perceived risk of online purchases and living in large cities. Despite some limitations, this paper has policy implications for China and other countries that have been influenced by the COVID-19 epidemic. Specifically, government support and regulation should focus on (i) ensuring the safety of food sold on the internet, (ii) protecting the carrier from becoming infected, and (iii) providing financial support to the poor since they may have difficulties in obtaining access to food living in small cities. Moreover, how to help those who are unable to purchase food online because of their technical skills (e.g., the elderly who are not familiar with smart phones or the internet) also deserves more attention for the government and the public.

The Effect of Dynamic Food Labels with Real-Time Feedback on Diet Quality: Results from a Randomized Controlled Trial

The rising prevalence of non-communicable diseases has brought attention to the importance of consuming a healthy diet. One strategy to improve diet quality is through front-of-pack (FOP) nutrition labels. Taking advantage of an online grocery store, we allowed consumers to choose the FOP labels they preferred, and combined this information with real-time feedback on the overall nutritional quality of the shopping basket. We hypothesized that these dynamic food labels with real-time feedback (DFLF) would improve nutritional quality of food purchases. This trial followed a two-arm (no-label control and DFLF) crossover design with 125 participants exposed to each condition once in random order via an online grocery store. A first difference regression model allowed for estimating the unbiased effect of the DFLF on diet quality, measured by the weighted average Nutri-Score (ranging 1 to 5) per serving (primary) and changes in select nutrients and calories. The mean weighted Nutri-Score was 0.4 (12.6%) higher in the DFLF arm (CI: [0.2, 0.6]) relative to the control. The DFLF also decreased the amount of sugar per serving by 0.9 g (CI: [−1.7, −0.0]) and total sugar per shop by 169.5 g (CI: [−284.5, −54.5]). The DFLF features significantly improved nutrition quality relative to no labelling, as measured by average Nutri-Score values. These results shed light on the considerable potential of the online shopping environment to improve diet quality through customization and real time feedback.

Changes in roll-your-own tobacco and cigarette sales volume and prices before, during and after plain packaging legislation in the UK

BACKGROUND

Plain packaging and minimum pack size legislation for tobacco products was introduced in the UK in May 2016, with a 1-year sell-off period until May 2017, during which both fully branded and plain packs of various sizes were legally available. This study investigates trends in prices of roll-your-own tobacco (RYO) before, during and after implementation of this legislation, and compares trends with those observed in the cigarette market.

METHODS

We used Nielsen Scantrack data for the period from March 2013 to June 2018 to describe trends in UK inflation-adjusted prices and volumes of both RYO and cigarettes, and linear regression to estimate changes in prices associated with the introduction of plain packaging and the minimum pack sizes of 30 g RYO and 20 cigarettes.

RESULTS

In contrast to a downward trend in cigarette sales volumes, RYO volumes rose throughout the study period. By the time plain packs accounted for 75% or more of sales, the average price of products sold in equivalent pack sizes had increased, relative to average prices in the year before implementation and with adjustment for tax changes, from 34.9 to 38.8 pence per gram for RYO (mean difference 4.26, 95% CI 3.99 to 4.53 pence, 12% increase), and from 38.6 to 41.13 pence for cigarettes (mean difference 2.53, 95% CI 2.24 to 2.83 pence, 7% increase) per cigarette.

CONCLUSIONS

New legislation resulted in higher prices for RYO and manufactured cigarettes. However, sales volumes of RYO continued to increase throughout the study period, perhaps because RYO remains a less expensive means of smoking tobacco.

Supply chain product quality control strategy in three types of distribution channels

Based on a three-stage stackelberg dynamic game analysis, this paper constructs a product quality control strategy model for three types of distribution channels (direct channel, retail channel and mixed channel) in a three-echelon supply chain, which is composed of one manufacturer, one retailer and the final customer. This paper studies how to design a distribution channel strategy and provides a product quality control strategy. Furthermore, this paper analyzes three types of distribution channels strategy in the context of how they influence a manufacturer’s product quality decision and quality prevention strategy, a retailer’s product pricing decision and quality inspection strategy, and the final customer’s product demand decision. We compare the manufacturer’s product quality level, quality prevention effort level, wholesale price, direct sale price and the retailer’s quality inspection effort level, retail price in three types of distribution channels and determine the manufacturer’s and retailer’s expected profits function and the final customer’s consumer surplus. In addition, we introduce the distribution channels demand elasticity ratio to analyze the influence of determining the product quality control strategy. Most importantly, we conduct a numerical sample analysis that will prove the model’s effectiveness and indicate a specific application in practice.

The Effects of Alcohol Warning Labels on Population Alcohol Consumption: An Interrupted Time Series Analysis of Alcohol Sales in Yukon, Canada

OBJECTIVE

There is limited evidence that alcohol warning labels (AWLs) affect population alcohol consumption. New evidence-informed AWLs were introduced in the sole government-run liquor store in Whitehorse, Yukon, that included a cancer warning (Ca), low-risk drinking guidelines (LRDGs) and standard drink (SD) messages. These temporarily replaced previous pregnancy warning labels. We test if the intervention was associated with reduced alcohol consumption.

METHOD

An interrupted time series study was designed to evaluate the effects of the AWLs on consumption for 28 months before and 14 months after starting the intervention. Neighboring regions of Yukon and Northwest Territories served as control sites. About 300,000 labels were applied to 98% of alcohol containers sold in Whitehorse during the intervention. Multilevel regression analyses of per capita alcohol sales data for people age 15 years and older were performed to examine consumption levels in the intervention and control sites before, during, and after the AWLs were introduced. Models were adjusted for demographic and economic characteristics over time and region.

RESULTS

Total per capita retail alcohol sales in Whitehorse decreased by 6.31% (t test p < .001) during the intervention. Per capita sales of labeled products decreased by 6.59% (t test p < .001), whereas sales of unlabeled products increased by 6.91% (t test p < .05). There was a still larger reduction occurring after the intervention when pregnancy warning labels were reintroduced (-9.97% and -10.29%, t test p < .001).

CONCLUSIONS

Applying new AWLs was associated with reduced population alcohol consumption. The results are consistent with an accumulating impact of the addition of varying and highly visible labels with impactful messages.

An optimization model for fleet sizing and empty pallet allocation considering CO2 emissions

Pallets are the most common equipment for transporting and storing goods. More and more companies are willing to rent pallets. Pallet rental companies need to transport pallets from their pallet rental service stations to customers and take these pallets back when they are unloaded. Hence, managers should scientifically configure vehicles for their pallet rental service stations. The fleet size, which indicates the amount and types of vehicles, can significantly affect the efficiency and costs of empty pallet allocation. Therefore, an optimization model for fleet sizing and empty pallet allocation is proposed using the methods of mixed-integer programming and stochastic programming. The objectives of this model are to maximize the profits of pallet rental companies and minimize carbon dioxide (CO₂) emissions from vehicles. A particle swarm optimization algorithm with inertia weight (IPSO) is developed to solve the proposed model because IPSO can avoid becoming trapped in local optima and is able to find a globally optimal solution within a reasonable number of iterations. A numerical example proves the effectiveness of the proposed model and IPSO. The results of numerical tests show that the amount of CO₂ emissions from vehicles can affect the decision on fleet sizing and empty pallet allocation. However, if the price, rental fees, or idle costs of the vehicles with low CO₂ emissions are too high, managers would not choose them.

Availability of Grocery Delivery to Food Deserts in States Participating in the Online Purchase Pilot

This cross-sectional study examines the availability of grocery delivery in census tracts designated as food deserts and among households within them.

Optimal Strategies of Product Price, Quality, and Corporate Environmental Responsibility

With the awakening of environmental consciousness, more and more firms desire to go “green” by shifting their focus of corporate social responsibility (CSR) from charitable contributions to environmental actions called corporate environmental responsibility (CER). We develop a monopoly differential game to depict optimal corporate strategies of product price, quality, and CER. Using the Hamilton–Jacobi–Bellman (HJB) equation, we analyze optimal feedback equilibrium strategies for pricing and investing in both quality and CER with/without government subsidies. Numerical simulations show that government subsidy can improve CER and profit.

An observational study to examine how cumulative impact zones influence alcohol availability from different types of licensed outlets in an inner London Borough

OBJECTIVES

Cumulative impact zones (CIZs) are a widely implemented local policy intended to restrict alcohol availability in areas proliferated with licensed outlets. Limited previous research has questioned their effectiveness and suggested they may play a more nuanced role in shaping local alcohol environments. This study evaluates the association between CIZ implementation and the number of licence applications made, and the number issued, relative to a control region.

DESIGN

A quantitative observational study.

SETTING

The inner London Borough of Southwark, which currently enforces three CIZs.

POPULATION

Licence applications received by Southwark Council's Licensing Authority between 1 April 2006 and 31 March 2017 (n=1254).

INTERVENTIONS

CIZ implementation.

PRIMARY OUTCOME MEASURES

Five outlet types were categorised and evaluated: drinking establishments, eateries, takeaways, off sales and other outlets. Primary outcome measures were the number of applications received and the number of licences issued. These were analysed using Poisson regression of counts over time.

RESULTS

Across all CIZs, implementation was associated with greater increases in the number of eateries in CIZ regions (incidence rate ratio (IRR)=1.58, 95% CI: 1.02-2.45, p=0.04) and number of takeaway venues (IRR=3.89, 95% CI: 1.32-11.49, p=0.01), relative to the control area. No discernible association was found for the remaining outlet types. Disaggregating by area indicated a 10-fold relative increase in the number of new eateries in Peckham CIZ (IRR=10.38, 95% CI: 1.39-77.66, p=0.02) and a fourfold relative increase in the number of newly licensed takeaways in Bankside CIZ (IRR=4.38, 95% CI: 1.20-15.91, p=0.03).

CONCLUSIONS

CIZs may be useful as policy levers to shape local alcohol environments to support the licensing goals of specific geographical areas and diversify the night-time economy.

Using the Event Analysis of Systemic Teamwork (EAST) broken-links approach to understand vulnerabilities to disruption in a darknet market

Darknet markets provide an anonymous, online platform for users to trade illicit drugs, fraudulent identity data, and other commodities. Although law enforcement agencies have been successful in seising many markets, the Darknet is an agile and dynamic environment and market activities often persist and emerge in a new form. Given this constantly changing environment, new ways of disrupting darknet markets are required. This study used Event Analysis of Systemic Teamwork (EAST) to analyse market activity and understand vulnerabilities to disruption. This involved using the EAST broken-links approach to assess the effects of compromising the transmission of information between tasks and between agents. The analysis identified critical vulnerabilities in the system, which included information involved in registering, depositing funds, communicating listing details to buyers, and communicating dispute resolution messages. This study indicates that systems ergonomics methods-in particular, EAST-can provide insight into system vulnerabilities that might be targeted for disruption. Practitioner summary This study provides a conceptualisation of the processes, people, structures, and information involved in the buying and selling of goods on a darknet market. Law enforcement agencies may use broken-links analyses to systematically consider the effects of their interventions.

Food Hygiene Knowledge and Practice among Food Vendors in Uyo, Nigeria

BACKGROUND

The role of food vendors in food hygiene and safety is an important one which, if neglected, could lead to outbreaks of food borne illnesses, currently major causes of morbidity and mortality, especially in sub-Saharan Africa and East Asia.

OBJECTIVE

The aim of this study was to assess the food hygiene knowledge and practices of food vendors in Uyo, Nigeria.

METHODS

This was a descriptive cross-sectional study. Data were collected using a pre-tested semi-structured questionnaire and analyzed with SPSS version 20.

RESULTS

A total of 125 respondents participated in the study. The mean age was 31.99 ± 10.51 years, with a male: female ratio of 1:1.04. Thirty-six (28.8%) respondents had good food hygiene knowledge (>75% of maximum scores) which was significantly associated with tertiary level of education and female sex (p<0.05). Only 11 (8.8%) however had good practice (>75% of maximum scores). Tertiary education, working less than 6 hours daily and food hygiene training were significantly associated with good practice scores (p<0.05). The relationship between food hygiene knowledge and practice was statistically significant (p=0.00). There were also statistically significant associations between having good knowledge of food hygiene and use of apron, hair covering, observing good sanitary conditions, water supply, waste disposal and protection of food from flies (p<0.05).

CONCLUSION

A link existed between having good level of knowledge and the hygiene practices of the respondents. Food vendors should therefore be adequately trained to equip them to offer sufficiently hygienic services, thus ensuring food safety among the consumers.

Evaluating the Use of Commercially Available Wearable Wristbands to Capture Adolescents' Daily Sleep Duration

Commercially available wearable devices are marketed as a means of objectively capturing daily sleep easily and inexpensively outside of the laboratory. Two ecological momentary assessment studies-with 120 older adolescents (aged 18-19) and 395 younger adolescents (aged 10-16)-captured nightly self-reported and wearable (Jawbone) recorded sleep duration. Self-reported and wearable recorded daily sleep duration were moderately correlated (r ~ .50), associations which were stronger on weekdays and among young adolescent boys. Older adolescents self-reported sleep duration closely corresponded with estimates from the wearable device, but younger adolescents reported having an hour more of sleep, on average, compared to device estimates. Self-reported, but not wearable-recorded, sleep duration and quality were consistently associated with daily well-being measures. Suggestions for the integration of commercially available wearable devices into future daily research with adolescents are provided.

Fitness preferential attachment as a driving mechanism in bitcoin transaction network

Bitcoin is the earliest cryptocurrency and among the most successful ones to date. Recently, its dynamical evolution has attracted the attention of the research community due to its completeness and richness in historical records. In this paper, we focus on the detailed evolution of bitcoin trading with the aim of elucidating the mechanism that drives the formation of the bitcoin transaction network. Our empirical investigation reveals that although the temporal properties of the transaction network possesses scale-free degree distribution like many other networks, its formation mechanism is different from the commonly assumed models of degree preferential attachment or wealth preferential attachment. By defining the fitness value of each node as the ability of the node to attract new connections, we have instead uncovered that the observed scale-free degree distribution results from the intrinsic fitness of each node following a power-law distribution. Our finding thus suggests that the "good-get-richer" rather than the "rich-get-richer" paradigm operates within the bitcoin ecosystem. Based on these findings, we propose a model that captures the temporal generative process by means of a fitness preferential attachment and data-driven birth/death mechanism. Our proposed model is able to produce structural properties in good agreement with those obtained from the empirical bitcoin network.

Managing product variety on online platform: Consumer heterogeneity and diseconomies of scope

Recent innovations in e-commerce have led to the emergence of online retailing platforms, where millions of products are sold. Most of these products are sold by third-party sellers who pay a fee for the e-retailer (called the platform owner). We investigate how the e-retailer manages the various products in the presence of consumer heterogeneity and diseconomies of scope. Our analytical results indicate that the e-retailer prefers the platform-selling mode when consumers have stronger heterogeneity or when the value of a product is high; moreover, the consumer heterogeneity benefits the e-retailer and hurts the supplier. We also analyze the effect of the relationship of among categories on the e-retailer’s choice. We show that the relationship among categories can invert the existing format. In addition, we find that the e-retailer may be better off and raise the number of products under strong diseconomies of scope when the categories are complements, and the opposite is true when the categories are substitutable.

A business process clustering algorithm using incremental covering arrays to explore search space and balanced Bayesian information criterion to evaluate quality of solutions

The reuse of business processes (BPs) requires similarities between them to be suitably identified. Various approaches have been introduced to address this problem, but many of them feature a high computational cost and a low level of automation. This paper presents a clustering algorithm that groups business processes retrieved from a multimodal search system (based on textual and structural information). The algorithm is based on Incremental Covering Arrays (ICAs) with different alphabets to determine the possible number of groups to be created for each row of the ICA. The proposed algorithm also incorporates Balanced Bayesian Information Criterion to determine the optimal number of groups and the best solution for each query. Experimental evaluation shows that the use of ICAs with strength four (4) and different alphabets reduces the number of solutions needed to be evaluated and optimizes the number of clusters. The proposed algorithm outperforms other algorithms in various measures (precision, recall, and F-measure) by between 12% and 88%. Friedman and Wilcoxon non-parametric tests gave a 90–95% significance level to the obtained results. Better options of repository search for BPs help companies to reuse them. By thus reusing BPs, managers and analysts can more easily get to know the evolution and trajectory of the company processes, a situation that could be expected to lead to improved managerial and commercial decision making.

International trade and investment: still the foundation for tackling nutrition related non-communicable diseases in the era of Trump?

Trade and investment policy strongly influence diet, nutrition, and risk of non-communicable disease—but what does this mean in the context of recent global political developments?

Determinants and efficiency of Pakistan's chemical products' exports: An application of stochastic frontier gravity model

The estimation of efficiency of industry-specific exports is very important to find exports’ gap and to frame exports promotion policy for targeted industry. This study attempts to investigate the main determinants of chemical products’ exports of Pakistan with 62 trading partners by applying Stochastic Frontier Analysis (SFA) on an augmented gravity model for a period 1995–2015. The results corroborate that chemical products’ exports follow gravity patterns. This study finds a negative and significant impact of import tariff on exports of chemical products while the positive impact of devaluation has been observed. Further, the estimations also take into account the impact of Preferential Trade Agreements (PTA), colonial links, common language, political disputes and contiguity by incorporating dummy variable for each variable and the expected positive effects are found except an insignificant effect of Contiguity. Further, the negative impact of political disputes is observed. The exports’ efficiency analyses reveal that Pakistan’s chemical exports are well below the optimal level and there exists a huge untapped exports’ potential with its neighboring, Middle Eastern and European countries.