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71.
Online social media drive the growth of unstructured text data. Many marketing applications require structuring this data at scales non-accessible to human coding, e.g., to detect communication shifts in sentiment or other researcher-defined content categories. Several methods have been proposed to automatically classify unstructured text. This paper compares the performance of ten such approaches (five lexicon-based, five machine learning algorithms) across 41 social media datasets covering major social media platforms, various sample sizes, and languages. So far, marketing research relies predominantly on support vector machines (SVM) and Linguistic Inquiry and Word Count (LIWC). Across all tasks we study, either random forest (RF) or naive Bayes (NB) performs best in terms of correctly uncovering human intuition. In particular, RF exhibits consistently high performance for three-class sentiment, NB for small samples sizes. SVM never outperform the remaining methods. All lexicon-based approaches, LIWC in particular, perform poorly compared with machine learning. In some applications, accuracies only slightly exceed chance. Since additional considerations of text classification choice are also in favor of NB and RF, our results suggest that marketing research can benefit from considering these alternatives.  相似文献   
72.
On the basis of a qualitative study of a subgroup of diversity professionals, external diversity and inclusion (D&I) consultants, we explore D&I consultants' discursive strategies and practices situated within organisational structures, relations, and interactions of power and knowledge. Theoretically, the research reveals how D&I consultants' own discursive strategies interact with existing organisational and societal discourses of diversity, incrementally shaping their continual evolution. A classification is developed, which sets out four approaches taken by consultants with regard to their discursive strategies in relation to clients. The findings suggest that HR practitioners need to work in tandem with external consultants to develop strategies to improve the status and legitimacy of diversity work if the field is to progress the organisational D&I agenda.  相似文献   
73.
Abstract

This research investigates the persistence of price–cost margin (PCM) and technical efficiency (TE) of firms and the relation between these two factors in 44 subsectors of the Indonesian food and beverage industry in the period 1980–2014. Data envelopment analysis with a bootstrapping approach is applied to estimate TE. An autoregressive model, accounting for endogeneity, is applied to estimate the persistence coefficients of PCM and TE. A cross-sectional regression model is also applied to estimate the relation between the persistence of the PCM and the persistence of TE. The results show that for these food and beverage firms, high PCM and low TE persist. Furthermore, the persistence of PCM negatively affects the persistence of TE in the industry.  相似文献   
74.
Abstract

In the pharmaceutical industry, a reverse payment (pay-for-delay) is a payment from an originator to a generic producer to delay her entry. In some recent cases, the US and EU antitrust authorities have banned these agreements per se, while in others they have used a rule of reason. This paper analyzes their dynamic effects and shows that a ban per se may reduce consumer surplus when the generic producer may go bankrupt and her financial situation is private information. Reverse payments are more beneficial when competition among few players is soft, the economy is in a downturn, and the period of drug usage after patent expiry is long. Results suggest that a rule of reason is more suited than a ban per se.  相似文献   
75.
Since the 1990s, firms in Japan have reduced their human capital investment in the workplace to minimize costs. Moreover, in response to the increase in the number of non-regular employees and turnover rates, workers need to have greater incentive to make the self-motivated investment in themselves for their self-protection. In this study, we first estimate the effects of workers’ self-motivated investment in themselves on wage rates. Next, we explore who is likely to participate in which training type and accordingly estimate the effects of the self-motivated investment on wage rates by training type. Our estimates controlling for individual-level fixed-effects indicate that the return is significantly positive and particularly high for practical training related to workers’ current jobs, and regular workers tend to self-select these higher-returns programs, while non-regular workers are more likely to enroll in lower-returns programs, such as schooling. This trend in investment in oneself could potentially increase the wage inequality between regular and non-regular workers through the self-selection of training types. Our estimates reveal that receiving the training and education benefit raises the likelihood for workers to participate in a high-return training program regardless of whether they are non-regular or regular workers. This suggests that government benefits on self-investment change workers’ self-selection of training type and serve to promote practical trainings that lead to high returns.  相似文献   
76.
政府补贴能否促进企业创新一直存在争议。与以往从资源视角探讨政府补贴与企业创新关系的研究不同,基于信号理论视角,以2012—2016年沪深A股非金融类上市公司为研究样本,通过剔除非研发补贴的噪音并控制样本自选择偏误,实证检验中国转型经济背景下,政府研发补贴对企业创新的微观政策效应,以及企业层面制度因素(产权性质)和区域层面制度因素(制度环境)对该效应的调节作用。研究发现,政府研发补贴释放的积极信号能够帮助企业获取外部创新资源,有效促进企业创新;相比于国有企业,政府研发补贴对非国有企业创新的激励效应更强;制度环境越好,政府研发补贴对企业创新的激励效应越强。研究理论丰富了科技创新政策有效性和信号理论相关研究。同时,研究发现,政府应继续加大对企业创新活动的补贴额度,不断深化所有制改革,为企业创新营造良好的外部制度环境;另外,企业还应充分发挥政府研发补贴信号的杠杆效应,拓宽外部创新资源获取渠道。  相似文献   
77.
基于资源基础理论和持续创新内生机制,利用435家高技术企业2010—2018年面板数据,对多元化战略对高技术企业创新持续性的影响进行探究。结果表明,产品多元化与创新持续性呈正U型关系,技术多元化对创新持续性具有正向促进作用,产品多元化与技术多元化协同效应对创新持续性具有负向影响;动态能力强化了产品多元化与创新持续性之间的正U型关系,并正向调节技术多元化与创新持续性之间的关系。在动态能力调节作用下,高技术企业产品多元化与技术多元化协同效应对创新持续性具有正向影响。  相似文献   
78.
苏南乡村地区一直是中国乡村建设的先行区域,特殊的纵横交错的水网结构构成了一个错综复杂的系统,呈现出其他地区不具有的复杂性和生态特殊性。随着城镇的扩张,乡村的发展建设使其水网空间的平衡发展面临极大的挑战。传统单一静态的规划方法逐渐显示出无法适应经济、社会等发展要求的缺陷。苏南乡村地区以水为核心,从水生态系统服务供需关系的视角下探究水网乡村的适应性规划策略更加适应当前的乡村现状和需求。以传统水网乡村空间形态转译为基础,建立水生态系统供需服务评估体系,在评估水生态系统服务供需能力的基础上,分析供需分异模式及供需矛盾。从构建乡村水域空间生态格局、乡村水域空间功能分区规划,以及乡村水域空间多情景预判3个方面,提出苏南水网乡村的适应性规划策略,并为水网乡村的生态实践提出新思路。  相似文献   
79.
Many experts agree that more agricultural investment is needed in the global South to improve local food security and reduce poverty. However, there is a lack of consensus about the types of investment needed to achieve these goals. This paper contributes to the literature on large agricultural investments and corresponding business models by inventorying and analysing such investments in Kenya’s Nanyuki area. We identify four clusters of business models that differ primarily by type of production and other distinct determinants, namely: demand from markets; access to land; land tenure regime and colonial history; actors involved; biophysical context; labour availability; and governance of the value chain via private standards. The study results shed light on the factors that help or hinder implementation of large agricultural investments and shape their impacts in the context of African land use systems. The way land is accessed represents one of the most-decisive factors determining the risks and opportunities associated with such projects. We find that most investments in the Nanyuki area occur on land bought or leased from private owners.  相似文献   
80.
Abstract

The paper aims to classify the quality cues and attributes of grated Parmigiano Reggiano cheese, an Italian traditional food cheese, exploring if they affect consumers’ quality perceptions and expectations. Analysis is based on a questionnaire administered in hypermarkets where grated Parmigiano Reggiano is sold. A factor analysis, using varimax rotation, and a cluster analysis, were performed, using the Stata 12 software package. The clusters used were: geographical origin and packaging (cluster 1); price, brand and quality certification (cluster 2); all sensory attributes (cluster 3); and a combination of sensory attributes with price, brand, and quality certification (cluster 4). This is the first study to examine the quality cues and attributes affecting quality perception and expectations of cheese for grated Parmigiano Reggiano from a consumer perspective. It is also the first to classify cheese attributes following a quality approach, encompassing previously studied sensory and other attributes.  相似文献   
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