《经济地理》创刊以来的知识溢出特征与变化

基于引证关系,利用知识图谱、社会网络分析等方法,对1981—2019年《经济地理》创刊以来知识溢出的特征与变化规律进行分析。经济地理学研究的专业综合性、学科交叉性特点,在《经济地理》期刊知识溢出的特征与变化中得以充分诠释。期刊知识溢出的作用与变化,不仅体现在促进作者合作网络形成与机构合作关系的深化上,也体现在对城市化、区域经济发展、区域旅游发展等研究领域的推动作用与变化上。期刊知识溢出的特征与变化在其主题构成、作者贡献、机构力量与前沿引领等的探讨中进一步得以明确。具体地,城市化研究的知识溢出作用,从城市化和城镇化、土地利用、生态环境等方面,逐渐转向新型城镇化、城市网络、生态环境、协调发展等主题;区域经济发展研究的知识溢出作用,经历了从经济联系转向产业集群、再转向空间相互作用关系的主题变化;区域旅游发展研究的知识溢出作用,则从旅游资源、旅游业、生态旅游等方面,逐步转向乡村旅游、旅游经济与协调发展等主题。以国家战略与发展政策为主要导向,促进国内经济地理学的研究与发展,是《经济地理》期刊知识溢出的核心内容与集中反映。     

Personalized goal-based investing via multi-stage stochastic goal programming

In this paper, we propose a goal-based investment model that is suitable for personalized wealth management. The model only requires a few intuitive inputs such as size of wealth, investment amount, and consumption goals from individual investors. In particular, a priority level can be assigned to each consumption goal and the model provides a holistic solution based on a sequential approach starting with the highest priority. This allows strict prioritization by maximizing the probability of achieving higher priority goals that are not affected by goals with lower priorities. Furthermore, the proposed model is formulated as a linear program that efficiently finds the optimal financial plan. With its simplicity, flexibility, and computational efficiency, the proposed goal-based investment model provides a new framework for automated investment management services.     

Microfinance institutions and International Financial Reporting Standards: An exploratory analysis

Previous studies analyzing firms’ incentives to choose international accounting standards show that firms with strong contracting incentives will be more likely to comply with International Financial Reporting Standards (IFRS). These studies are mostly centered on developed economies and are based on European and US data. Little is known about development finance organizations’ incentives to choose to draft their financial statements according to IFRS. Because commercialized microfinance institutions (MFIs) have strong contracting incentives, we investigate whether commercialization drives the choice of IFRS and study a pooled international sample of MFIs’ audited financial statements extracted from the MIX from 2007 to 2014. Consistent with our predictions, evidence shows that commercialization and maturity (age) are likely to drive the MFIs’ choice to comply with IFRS. Results are robust after controlling for heterogeneity in national regulations with regard to IFRS.     

Security regulations,access to capital markets,and firm performance: Evidence from China

This study explores the cost of security regulations in China, where firms are required to meet a certain profitability benchmark before applying for permission to raise more equity via secondary equity offerings (SEOs). Using a difference-in-differences setting, we show that firms affected by the regulation (i.e., firms with high external financing demands (EFD) but profitability lower than the regulatory requirement) significantly underperform their counterparts, while unaffected firms do not. The affected firms’ performance decline increases (decreases) when the requirement of profitability is more (less) restricted. Consistently, the three-day cumulative abnormal return (CAR) of firms with high EFD is significantly negative (positive) when the regulation is tightened (loosened). Our study provides evidence on how the cost of regulation affects companies that have growth opportunities.     

Asset pricing and energy consumption risk

This paper proposes energy consumption in the US as a new measure for the consumption capital asset pricing model. We find that (i) industrial energy growth produces reasonable values for the relative risk aversion coefficient and the implied risk-free rate; (ii) compared to alternative consumption measures, industrial energy performs well in explaining the cross-sectional variation in stock returns with the lowest implied risk aversion and pricing errors; (iii) the industrial energy consumption risk model performs equally well as the Fama–French three-factor model in the cross-sectional asset pricing tests; and (iv) total energy consumption risk is priced in the presence of the Fama–French factor risks.     

The impact of shareholders and creditors rights on IPO performance: An international study

This paper examines the impact of cross-country variation in shareholders' and debt holders' rights on post-IPO performance and survival of newly listed stocks across the globe. Using a sample of 10,490 initial public offerings (IPOs) in 40 countries between 2000 and 2013, we find that post-IPO performance and survival is better in countries with stronger shareholder protection, but the impact of creditor protection is negative i.e. stronger creditor protection leads to poor post-IPO performance and survival. This effect is driven by rules requiring creditors’ consent for company reorganization and the mandatory replacement of incumbent managers. Reputable IPO advisors exacerbate the positive impact of shareholder rights and the negative impact of creditor rights.     

辣木树不同部位γ-氨基丁酸的HPLC分析

用高效液相色谱法检测了辣木树不同部位γ-氨基丁酸的含量,结果表明:每100 g样品中,辣木果实、叶、果皮、花、根、籽及茎中的GABA含量分别为378.39、275.64、194.15、96.42、69.14、27.32 mg与0.00 mg。由此可见,辣木树中富含GABA,且幼嫩部位含量较高,本研究可为辣木产品的质量评价、开发利用以及辣木树中GABA的合成部位与运输情况研究提供理论参考。     

Economic burden associated with inadequate antidepressant medication management among patients with depression and known cardiovascular diseases: insights from a United States–based retrospective claims database analysis

Abstract

Aims: The current study examined the association between insufficient major depressive disorder (MDD) care and healthcare resource use (HCRU) and costs among patients with prior myocardial infarction (MI) or stroke.

Methods: This was a retrospective study conducted using the MarketScan Claims Database (2010–2015). The date of the first MI/stroke diagnosis was defined as the cardiovascular disease (CVD) index date and the first date of a subsequent MDD diagnosis was the index MDD date. Adequacy of MDD care was assessed during the 90 days following the index MDD date (profiling period) using 2 measures: dosage adequacy (average fluoxetine equivalent dose of ≥20?mg/day for nonelderly and ≥10?mg/day for elderly patients) and duration adequacy (measured as the proportion of days covered of 80% or higher for all MDD drugs). Study outcomes included all-cause and CVD-related HCRU and costs which were determined from the end of the profiling period until the end of study follow-up. Propensity-score adjusted generalized linear models (GLMs) were used to compare patients receiving adequate versus inadequate MDD care in terms of study outcomes.

Results: Of 1,568 CVD patients who were treated for MDD, 937 (59.8%) were categorized as receiving inadequate MDD care. Results from the GLMs suggested that patients receiving inadequate MDD care had 14% more all-cause hospitalizations, 4% more all-cause outpatient visits, 17% more CVD-related outpatient visits, 13% more CVD-related emergency room (ER) visits, higher per patient per year CVD-related hospitalization costs ($21,485 vs. $17,756), higher all-cause outpatient costs ($2,820 vs. $2,055), and higher CVD-related outpatient costs ($520 vs. $434) compared to patients receiving adequate MDD care.

Limitations: Clinical information such as depression severity and frailty, which are potential predictors of adverse CVD outcomes, could not be ascertained using administrative claims data.

Conclusions: Among post-MI and post-stroke patients, inadequate MDD care was associated with a significantly higher economic burden.     

How the iPhone Widens the U.S. Trade Deficit with China: The Case of the iPhone X

Through an examination of the case of the iPhone X, this paper demonstrates that Chinese companies involved in the production of the iPhone X have moved up along the global value chain. According to the bill of materials, those companies contributed 25.4% of the value added of the iPhone X. About 45% of the value added of the iPhone X originated in Japan, South Korea, and other economies. The iPhone trade remains a significant element of the statistical distortion of the China–US bilateral trade imbalance. In terms of gross value, the import of one iPhone X results in a USD332.75 trade deficit for the US; measured in terms of the value added, however the deficit is a mere USD104. The depreciation of the Chinese yuan (CNY) has very limited power to counterbalance the tariffs imposed by the Trump administration because the foreign value added embedded in Chinese exports is 33.9% on average. Simulation results show that to counterbalance a 25% tariff, the CNY would have to depreciate by 43.3% against the US dollar on average, and to fully compensate for a 25% tariff burden on the iPhone X, a 400% depreciation of the CNY would be necessary. Hedging the risk of the punitive U.S. tariffs by depreciating the CNY is impossible.     

国际研发合作对 全球价值链分工地位的影响 ——基于吸收能力的门槛效应

基于知识吸收能力的视角，从理论和实证上考察国际研发合作对全球价值链分工地位攀升的作用及其门槛变量的影响。研究结果表明：在控制其他变量的基础上，国际研发合作能够显著地促进全球价值链分工地位攀升。进一步地，国际研发合作对全球价值链分工地位的影响还要受到经济体吸收能力的影响，要素禀赋、金融发展、人力资本、研发能力及制度环境等吸收能力分项维度对国际研发合作与全球价值链分工地位之间的关系具有显著的门槛调节效应。在全球研发网络和全球产业价值链加速融合的背景下，研究结论对中国企业通过选择国际合作研发策略、嵌入全球研发创新网络、强化知识吸收能力以进一步提升企业国际竞争力具有重要的启示意义。