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1.
Interest in supporting local and regional food systems is rising and food hubs have attracted considerable attention among Federal, State, and local policymakers. This study explores the problem of endogenous hub location in fresh produce value chains in the Northeastern United States. To overcome limitations in the literature, we incorporate the effects of economies of scale and production seasonality into our models. Three experimental models are designed to examine the effects of alternatively applying yearly, quarterly, and monthly data on model solutions. We explicitly assess how interactions of scale economies and seasonality influence the structure and spatial attributes of an optimal regional produce aggregation hub system. The three models generate marketed different solutions and in many respects they lead to different conclusions about developing local/regional supply chains. The monthly model allows for production seasonality and actual hub operation cycle frequency and thus leads to more efficient hub solution with rich policy implications.  相似文献   
2.
Additive manufacturing (AM) appears to be a particularly attractive use case for blockchain. This research combines inductive in‐depth interviews with the Delphi method to explore what potentials blockchain technology in AM creates, which adoption barriers firms need to overcome, and how supply chains will be affected by the integration of these two potentially disruptive technologies. The results suggest opportunities that are related to intellectual property (IP) rights management, the monitoring of printed parts throughout their lifecycle, process improvements, and data security. The most important barriers for blockchain adoption in AM are an absence of blockchain‐skilled specialists on the labor market, missing governance mechanisms, and a lack of firm‐internal technical expertise. By addressing important limitations of AM, blockchain is expected to improve the competitiveness of AM in parts’ production, catalyzing the trend toward more decentralized manufacturing resulting in more agile, resilient, and flexible supply chains and reduced logistics costs. Beyond that, blockchain‐based AM platforms are expected to enhance supply chain visibility, drive supply chain digitalization, support supply chain finance, and contribute to the emergence of shared factory systems.  相似文献   
3.
This study uses GARCH-EVT-copula and ARMA-GARCH-EVT-copula models to perform out-of-sample forecasts and simulate one-day-ahead returns for ten stock indexes. We construct optimal portfolios based on the global minimum variance (GMV), minimum conditional value-at-risk (Min-CVaR) and certainty equivalence tangency (CET) criteria, and model the dependence structure between stock market returns by employing elliptical (Student-t and Gaussian) and Archimedean (Clayton, Frank and Gumbel) copulas. We analyze the performances of 288 risk modeling portfolio strategies using out-of-sample back-testing. Our main finding is that the CET portfolio, based on ARMA-GARCH-EVT-copula forecasts, outperforms the benchmark portfolio based on historical returns. The regression analyses show that GARCH-EVT forecasting models, which use Gaussian or Student-t copulas, are best at reducing the portfolio risk.  相似文献   
4.
Facing the challenge of climate change, innovations that imply environmental benefits create business opportunities for entrepreneurs. This paper analyzes innovation capabilities of startups in Cleantech and how the innovation outcomes of those startups develop over time. Based on the Mannheim Foundation Panel and applying propensity score matching, a cohort of 567 Cleantech startups is analyzed and compared with a control cohort of non‐Cleantech startups. We find that startups in Cleantech have, on average, higher technological capabilities compared with all other startups. Our econometric evidence shows that Cleantech startups are more likely to combine existing technology in a novel way. Finally, we find that Cleantech startups develop more market novelties in subsequent years when compared with their control group peers.  相似文献   
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6.
This paper analyzes the effect of lifting primary school fees on educational attainment in Uganda. After the abolishment of school fees in 1997, the enrollment rate more than doubled. Two decades later, we know little about the effect of the policy on educational attainment. With recent data on eight cohorts exposed to free education, we analyze the impact of the policy on years of completed primary school, completion of primary school, and transitioning to secondary school. We use a straightforward regression analysis with cohort dummies and household fixed effects to control for unobserved heterogeneity. We find that lifting school fees had no effect on the years of primary school achievement and the likelihood of primary school completion. We find some weak evidence that the likelihood of those who completed primary education to start secondary school increased after Universal Primary Education.  相似文献   
7.
Drawing on external ideas through crowdsourcing has become common practice for firms that seek to improve and extend their product portfolios. As these initiatives often address the users of products, it is essential for firms to recognize those attributes that determine these individuals' willingness to share their ideas. This study takes the example of the automotive industry to examine how three attributes of car drivers determine their sharing behavior – that is, altruism, psychological ownership of ideas, and trust in car manufacturers. Our findings suggest that trust and altruism strengthen idea sharing, while psychological ownership weakens it. Furthermore, we find that car drivers' perception of sharing‐related risk acts as an important boundary condition for these relationships.  相似文献   
8.
Human resource practitioners play a crucial role in promoting equitable treatment of persons with disabilities, and practitioner's decisions should be guided by solid evidence‐based research. We offer a systematic review of the empirical research on the treatment of persons with disabilities in organizations, using Stone and Colella's seminal theoretical model of the factors influencing the treatment of persons with disabilities in work organizations, to ask: What does the available research reveal about workplace treatment of persons with disabilities, and what remains understudied? Our review of 88 empirical studies from management, rehabilitation, psychology, and sociology research highlights seven gaps and limitations in extant research: (a) implicit definitions of workplace treatment; (b) neglect of national context variation; (c) missing differentiation between disability populations; (d) overreliance on available data sets; (e) predominance of single‐source, cross‐sectional data; (f) neglect of individual differences and identities in the presence of disability; and (g) lack of specificity on underlying stigma processes. To support the development of more inclusive workplaces, we recommend increased research collaborations between human resource researchers and practitioners on the study of specific disabilities and contexts, and efforts to define and expand notions of treatment to capture more nuanced outcomes.  相似文献   
9.
We study how disclosure requirements for large short positions affect investor behavior and security prices. Short positions accumulate just below the applicable disclosure threshold as certain investors never disclose any of their positions. Further tests suggest that this secrecy is part of investors’ general policy of avoiding disclosure to protect their unique, profitable investment strategies against reverse engineering by competitors. No evidence supports the notion that short sellers avoid disclosure because of potential adverse effects on securities' lending fees, risk of recall, or short squeezes. Finally, the evasive behavior by short sellers in response to transparency regulations hampers price discovery.  相似文献   
10.
Integrating insights from the strategic goal literature and the knowledge‐based view of the firm, this article proposes that the pursuit of social and economic strategic goals by commercial firms affects their innovation performance through different knowledge sourcing activities. The strategic goals, knowledge sourcing practices, and innovation performance of 1257 Belgian firms are investigated. Results show that both social and economic strategic goals are associated with the use of external information sources, but only the pursuit of social goals inspires firms to engage in external collaboration. No evidence is found of an inherent conflict between social and economic strategic goals. Instead, the two types of goals are independent of each other, that is, an emphasis on social goals does not preclude an emphasis on economic goals and vice versa. Moreover, firms’ external knowledge sourcing and innovation performance benefit most when strongly held social goals align with strongly held economic goals. These findings offer new insight into the nature and the effects of goal multiplicity among commercial firms. They open up a new perspective on the potential positive effects of the joint pursuit of social and economic strategic goals instead of seeing them as inherently conflicting, as past research has typically done. We illustrate how social strategic goals can deliver unique benefits to a firm, independently of and in addition to economic strategic goals. Our findings also contribute to the open innovation literature by revealing strategic goals as a driver of firms’ knowledge sourcing practices. Our findings suggest that solely emphasizing economic goals may be one reason why firms struggle to implement open innovation practices and do not reap their full benefits. The practical implications of our research are discussed.  相似文献   
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