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981.
《Telecommunications Policy》2018,42(3):241-252
Mobile communication failure can occur when mobile traffic exceeds the manageable level. This depends on frequency bandwidth. Mobile communication failure causes inconveniences in a user's daily life that lead to social and economic damage. To address this issue, mobile telecommunications companies deploy additional bandwidths and develop new technologies, but these are costly strategies. This study applies a spike model based on a contingent valuation method (CVM) to measure the inconvenience cost resulting from mobile communication failure. The mean monthly willingness-to-pay (WTP) to avoid communication failure per user is estimated to be KRW 898.14 (USD 0.80) over a period of five years in our study. The inconvenience cost borne by the population is estimated to be KRW 2.97 trillion (USD 2.61 billion). Users experiencing greater frequency of communication failure are found to be willing to pay more to avoid the inconvenience. When excluding respondents citing zero-WTP, the mean WTP per user was calculated to be KRW 3426.41 (USD 3.01). Data traffic usage and frequency at which communication failure is experienced are variables that exhibit statistically significant effects on WTP to avoid mobile communication failure. Overall, estimation results show that a price discrimination based on data traffic usage or quality can be considered by mobile telecommunications companies and regulators to address the issue of data traffic inducing mobile communication failure. 相似文献
982.
《Telecommunications Policy》2018,42(4):293-303
The advanced development of broadband access is an inevitable step toward supportive daily lives and sustainable economic growth. However, the decisive outcome of the development relies heavily on the demand side. Consumer choice among advanced Internet broadband technologies will determine the achievement of the development. This study aims to illustrate that consumer decisions on choices of advanced Internet access are influenced by the emergence of the Internet of Things (IoT) applications. A bivariate probit model is applied to examine the effects of IoT, consumer's individual characteristics, and their current use of networks on their decision pertaining to the choice of advanced Internet access. Using Thailand as a case study, the result indicates that the emergence of IoT applications accelerates the adoption of both advanced mobile broadband (5G) and advanced fixed broadband (FTTH). This finding may help policy makers to optimize the future direction of the Internet infrastructure development in Thailand, and also countries in a similar stage. 相似文献
983.
《Telecommunications Policy》2018,42(5):345-360
The diffusion and adoption of modern information technology provide new chance for China to close urban-rural income gap. This paper uses China's provincial panel data from 2002 to 2013 to investigate the effect of computer penetration on rural residents' income. A public program aiming to connect every village with broadband Internet and other rural facilities provides plausibly exogenous variation in rural residents' availability and adoption of the broadband Internet, which is used to explore the instrument variable for rural computer penetration. The results show that rural computer penetration tends to increase rural residents' income over time, but the average effect remains limited. The dynamic panel threshold effects model, which allows for both the threshold variable and other covariates to be endogenous, is further used to explore the constraints of the income-increase effect of rural computer penetration. It shows that the effect is at least doubled over the average effect estimated from instrument variables method, once the digital divide causes are removed. Our findings have important implications for the government to increase rural residents' income and reduce urban-rural income gap by encouraging rural computer usage and removing the digital divide. 相似文献
984.
《Telecommunications Policy》2018,42(6):464-473
This paper explores the determinants of the individual's decision to perform cross-border e-commerce (CBeC). The European Union (EU) is especially interested in the promotion of CBeC because it is an important tool in its strategy to achieve the Digital Single Market in Europe. In this paper official data is used from a representative survey of 16,209 individuals on ICT usage by households and individuals that was carried out in Spain by the National Institute of Statistics (INE) for the year 2016. Using a standard neoclassical utility maximization framework, and logistic regression techniques, the results show that being a male is positively related to the probability of practicing CBeC. Education is positively and significantly related to the probability of being involved in CBeC with EU countries. Computer and Internet Skills are significant and positive factors in explaining CBeC (either with EU countries or with the rest of the world). The variable “how often the consumer sees other customer reviews before buying online”, has a positive effect. Foreign nationality also increases the likelihood of using CBeC. To promote CBeC in Spain measures towards developing digital skills, Internet trust and use of online information reviews of goods and services are discussed. 相似文献
985.
《Food Policy》2018
Cooperatives are established to improve farmers' production conditions, to increase their bargaining power and to enable them to benefit from modern value chains. In China, farmers are members of a cooperative for multiple reasons. Little is known on whether and how cooperative membership affects farmers’ choice of marketing channels. This paper examines determinants of farmers’ choice of marketing channels, especially how cooperative membership impacts upon this choice. Our analysis is based on survey data collected in 2015 among 625 apple growing farm households in the provinces Shaanxi and Shandong. We employ endogenous switching probit models to deal with potential endogeneity of membership in estimating the determinants of marketing channel choices. We find that cooperative membership has a positive impact on selling to wholesalers and a negative impact on selling to small dealers, but no significant impact on selling to the cooperative itself. As products sold through cooperatives generally comply with relatively stringent food quality and safety standards, these results imply that policies promoting cooperative members to sell their products through cooperatives are likely to have a significant impact on food quality and food safety in China. 相似文献
986.
为了解决同时含有随机因素和灰色因素的不确定规划问题,通过结合区间灰数所属区间两个端点的随机性,给出随机区间灰数和随机区间灰函数的定义,提出了随机灰规划模型。通过综合效应函数理论用随机变量期望值和方差综合量化表示灰数所属区间的两个端点值。应用该理论对综合量化后的两个端点值继续进行综合量化,从而将随机灰规划转化为确定型规划问题。应用遗传算法进行求解。通过综合效应函数的理念,综合随机变量的期望和方差,同时综合区间灰数的区间因素,将随机灰规划数学模型转化为确定型规划模型即基于效应的随机灰规划模型。通过选取不同的综合效应函数,得到了关于不同决策意识下的随机灰规划的最优解。这个方法可为决策者进行不确定决策提供参考。 相似文献
987.
为解决实际应用中克拉维酸钾峰与后相邻杂质的分离度达不到要求的问题,建立了一种同时测定阿莫西林克拉维酸钾片中阿莫西林和克拉维酸钾含量的新方法,采用反相高效液相色谱法(RP-HPLC),Ultimate AQ-C_(18)色谱柱(4.6mm×250 mm,5μm),以pH值为4.4的0.05 mol/L磷酸二氢钠缓冲液为流动相,柱温为35℃,流速为1.0mL/min,检测波长为220nm。结果表明:阿莫西林和克拉维酸钾两主峰与相邻杂质得到完全基线分离,分离度大于1.5;克拉维酸钾对照品溶液质量浓度为0.050 0~0.500 1mg/mL时与峰面积的线性关系良好(r=0.999 8),平均回收率(n=9)为100.14%,RSD值为0.24%;阿莫西林对照品溶液质量浓度为0.100 0~1.000 1mg/mL时与峰面积的线性关系良好(r=0.999 9),平均回收率(n=9)为100.45%,RSD值为0.17%。与原有的《中华人民共和国药典》方法相比,新的阿莫西林克拉维酸钾片含量测定方法专属性好,准确度高,操作简便快捷,结果可靠,可作为一种质量控制方法。 相似文献
988.
Do ongoing networks block out new friends? Reconciling the embeddedness constraint dilemma on new alliance partner addition 下载免费PDF全文
Research Summary: This study addresses a theoretical dilemma regarding how alliance network constraint (reflected by network cohesion) affects a firm’s alliance formation with new partners. Using a network pluralism approach, we separate a firm’s ego alliance network into two activity‐based networks—an exploratory network and an exploitative network—based on the primary value chain activity involved in each alliance. We argue that the cohesion of exploratory or exploitative networks has an inverted U‐shaped effect on the addition of new partners in the same activity‐based network, and a positive effect on the addition of new partners in the other network. Results based on data from the biotechnology industry largely support our predictions with one exception. Our study contributes to both scholarly understanding of network embeddedness and alliance practice. Managerial Summary: The structure of firms’ ongoing alliance networks may have paradoxical implications for their efforts to search for and form alliance with new partners. That is, when a firm’s alliance partners are tightly connected with each other, the cohesive network tends to both encourage and impede the focal firm to add new partners. We resolve this dilemma by showing that when a firm is deeply entrenched in a cohesive alliance network conducting a certain type of activities (e.g., R&D activities), it may not easily add new R&D alliance partners. However, it may still be able to escape from the cohesive R&D alliance network by seeking new partners conducting other activities (e.g., manufacturing activities). 相似文献
989.
Research Summary: Regulatory bodies often wrestle with the thorny question of whether to mandate a governance practice or allow for organic adoption. While mandates afford rapid diffusion, we theorize that they also result in ceremonial adoptions. Leveraging a quasi‐natural experiment, we compare adoption outcomes for a governance practice—lead director adoption—that was mandated by the NYSE but not the NASDAQ. We find that NYSE firms are more likely than NASDAQ firms to have installed a lead director as a symbolic management tactic, so their lead directors are less effectual. We also find that transient institutional investors are deceived by this symbolic management, but dedicated institutional investors are not. Managerial Summary: Shareholders and analysts often desire to see companies introduce strict governance measures, such as proxy access and independent boards. Consequently, regulatory bodies often wrestle with the thorny issue of whether and when to mandate such practices for all companies. What they might not realize is that mandates may not work as well as they seem. Although more companies adopt reform under a mandate, they do so merely as a symbolic gesture. We look at one governance reform—appointing a lead director—finding that companies who introduce this reform as a result of a mandate appoint someone that is relatively toothless. We also find, though, that savvy investors are not actually fooled by this tactic and will trade out of firms that attempt such symbolic management. 相似文献
990.
Research Summary: We propose that due to financial market pressures, managers are forward‐looking in their search and decision processes and focus on meeting performance targets set by the financial community. Using panel data on S&P 100 companies, we find that pressure felt by management to meet the analyst consensus earnings estimate influences the extent of corporate downsizing. Moreover, our results show that high levels of institutional investor stock ownership and CEO power attenuate managers’ sensitivity to financial market pressures, while high levels of analyst coverage increase their sensitivity. Managerial Summary: In this study we examine how financial market pressures influence managers’ downsizing decisions. We argue that investment analysts’ earnings estimates represent important performance targets to which managers aspire. If firms fail to meet analysts’ expectations, the stock price will suffer. This study shows that managers utilize corporate downsizing to address the potential shortfall between a firm's future performance and the analyst consensus earnings estimate. In addition, we find that managers’ concerns over meeting analysts’ earnings estimates are influenced by various contextual factors such as institutional investor stock ownership, CEO power, and high levels of analyst coverage. 相似文献