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We provide an introduction to the special issue on subsistence marketplaces. We briefly describe the stream of subsistence marketplaces, and the conference series associated with the call for papers. We provide a brief overview of the diverse set of papers in the special section.  相似文献   
153.
Objective: To assess long-term healthcare costs related to ischemic stroke and systemic embolism (stroke/SE) and major bleeding (MB) events in patients with non-valvular atrial fibrillation (NVAF) treated with non-vitamin K antagonist oral anticoagulants (NOACs).

Materials and methods: Optum’s Clinformatics Data Mart database from 1/2009–12/2016 was analyzed. Adult patients with ≥1 stroke/SE hospitalization (index date) were matched 1:1 to patients without stroke/SE (random index date), based on propensity scores. Patients with an MB event were matched to patients without MB. All patients had an NOAC dispensing overlapping index date, ≥12?months of eligibility pre-index date, and ≥1 NVAF diagnosis. The observation period spanned from the index date until the earliest date of death, switch to warfarin, end of insurance coverage, or end of data availability. Mean costs were evaluated: (1) per-patient-per-year (PPPY) and (2) at 1, 2, 3, and 4?years using Lin's method.

Results: The cost differences were, respectively, $48,807 and $28,298 PPPY for NOAC users with stroke/SE (n?=?1,340) and those with MB (n?=?3,774) events compared to controls. Cost differences of patients with vs without stroke/SE were $49,876, $51,627, $57,822, and $60,691 at 1, 2, 3, and 4?years post-index, respectively (p?p?Limitations: Limitations include unobserved confounders, coding and/or billing inaccuracies, limited sample sizes over longer follow-up, and the under-reporting of mortality for deaths occurring after 2011.

Conclusions: The incremental healthcare costs incurred by patients with vs without stroke/SE was nearly twice as high as those of patients with vs without MB. Moreover, each additional year up to 4?years after the first event was associated with an incremental cost for patients with a stroke/SE or MB event compared to those without an event.  相似文献   
154.
This article considers the model of voluntary, consensus based standardization as developed through the British Standards Institution (BSI) and its contribution to learning and productivity growth. It discusses the significant role played by professional engineers in the model's introduction, its extension at home, and its imitation overseas. It is argued that by 1931 the BSI catalogue of standards represented a considerable stock of codified knowledge whose growth reflected underlying aggregate technological opportunities, assisting in their transformation into technological advance. To help validate this claim, a measure of the size of the BSI catalogue of standards is incorporated into an econometric model of aggregate productivity growth in Britain. Findings show that the growth of the standards catalogue is associated with a substantial proportion of labour productivity growth over the period 1931–2009. Estimates relating to the short‐run dynamics involved are consistent with the idea that there are causal linkages running from standards to growth. When interpreting these findings, it is argued that the overall weight of historical evidence points to standardization—coordinated through the BSI—as providing an important path of learning for the British economy over the period considered.  相似文献   
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This special issue focuses on entrepreneurship, innovation and enterprise dynamics, as these key components of any prospering economy are at the heart of the current policy discussion. It gathers the latest national and comparative cross-country evidence about: new business venture formation and the role of framework conditions in fostering entrepreneurial activities; the determinants and outcomes of firms’ innovative activities and, more generally, of business and innovation dynamics; and the determinants and patterns of post-entry firm growth performance. The contributions synthesised in this introductory piece all rely on sound micro-level data and robust econometrics and propose novel findings that are relevant for policy making. Among them, that risk aversion encourages individuals to invest in balanced skill profiles, making them more likely to become entrepreneurs; and that while micro firms may grow when they are young, they are less likely to do so when old.  相似文献   
158.
This article presents an analysis of occupational structure, a key component of the ‘Little Divergence’, in an eastern‐central European economy under the second serfdom, using data on 6,983 Bohemian villages in 1654. Non‐agricultural activity was lower than in western Europe, but varied positively with village size, pastoral agriculture, sub‐peasant strata, Jews, freemen, female headship, and mills, and negatively with arable agriculture and towns. It showed a curvilinear relationship with the ‘second serfdom’, as proxied by landlord presence on village holdings. Landlord presence in serf villages also reversed the positive effects of female headship and mills on non‐agricultural activities. Under the second serfdom, landlords encouraged serf activities from which they could extract rents, while stifling others which threatened manorial interests.  相似文献   
159.
Abstract

Unsignalized intersections in developing countries experience many serious conflicts between cross-traffic due to indiscipline traffic manoeuvrability. Historically, Post Encroachment Time (PET) has gained attention as a proximal indicator to analyze crossing conflicts. However, identifying an appropriate PET threshold to classify critical conflicts for highly heterogeneous traffic scenario is still an unexplored area. Consequently, this study proposes a novel approach of PET threshold identification with proof of application by collecting data from ten intersections located on four-lane intercity highways in the National Capital Region (NCR), India. Both crossing conflicts and right-turn related crash data (for the left-hand drive) are collected. Their correlations are thoroughly studied for each PET threshold using a quantitative technique considering all and individual vehicle categories. Finally, a qualitative analysis is done by ranking the sites based on cumulative PET and related crashes to verify the proposed quantitative technique. A PET threshold of 1?s is obtained from both the techniques which can be used to identify critical conflicts for unsignalized intersections located on four-lane intercity highways. The proposed methodology will serve as an alternative, faster and effective tool to evaluate the hazardousness of unsignalized intersections located on intercity highways under highly heterogeneous traffic condition.  相似文献   
160.
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