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1.
We study how natural resource rents affect the risk of internal conflict within countries and how the federal structure of countries influences this relationship. Natural resource abundance may induce excessive rent-seeking and thus increase the risk of internal conflict. Fiscal and political decentralization as an institutional arrangement for rent-sharing and political codetermination of regions within a country may limit the destructive effect of natural resource rents on internal stability. Using cross-country and panel data from more than 90 countries covering the period 1984–2004, we find evidence that natural resource rents indeed increase the risk of internal conflict, but this relationship is significantly mitigated by political decentralization. 相似文献
2.
Jochen Hartmann Juliana Huppertz Christina Schamp Mark Heitmann 《International Journal of Research in Marketing》2019,36(1):20-38
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
3.
本文建立了包菜中对硫磷残留量的气相色谱-火焰光度检测器(FPD)检测方法.样品用QuEChERS方法进行前处理后,采用外标法进行定量.对硫磷在80.0~1000μg·L-1范围中线性关系良好(r=0.9994),方法添加回收率为96.0%~111%,相对标准偏差RSD为2.5%~4.3%,方法的检出限为0.161μg·kg-1,能够满足蔬菜中对硫磷残留量的分析要求. 相似文献
4.
Self-service technologies (SSTs) increasingly permeate retail space. Yet, sometimes retailers decide to revert to human-delivered service mode by discontinuing their incumbent SST. In this study, we examine how self-checkout (SCO) discontinuance affects customers’ perceptions of SCO technology and purchase behavior. We conduct a natural field experiment by surveying two groups of customers pre- and post- SCO discontinuance: treatment group (who experience discontinuance) and control group (who do not experience discontinuance). Leveraging difference-in-differences analyses, we find that SCO discontinuance results in decreases in customers’ satisfaction with technology, intentions to use technology, perceived simplicity of technology, and basket size. Our results inform managers of the potential downsides of discontinuing SST and provide corroborating evidence of the technology’s benefits. 相似文献
5.
We exploit a natural experiment related to the German re-unification to address whether disutility from income comparisons affects attitudes towards foreigners. Our empirical approach rests upon East German individuals with West German relatives and friends. We use the exogenous variation of wealth of West Germans shortly after the fall of the Berlin Wall as an instrument to identify the effect of disutility from income comparisons on East Germans’ attitudes. We find robust evidence that East Germans express more negative attitudes towards foreigners, particularly from low-wage countries, if they worry about their economic status compared to better-off West Germans. 相似文献
6.
Natural personal care products are gaining popularity due to their benefits in terms of health and well-being. However, consumers are wary of these products and are guided by the fake news circulating about them. Since natural product consumption offers several personal and environmental benefits, it would be worthwhile to understand consumers’ tendency to let fake news influence their consumption decisions. Accordingly, the current study examined the association of fake news and purchasing behaviour towards natural personal care products, utilising Stimulus-Organism-Behaviour-Consequence (SOBC) as the theoretical framework. The study proposed openness to change as the stimulus, perceived benefits and perceived risks as organismic internal states, purchase intentions as the behaviour, and the propensity of believing and acting on fake news as the consequence, which is further associated with system trust. The model was tested by analysing data collected from 390 existing consumers, considering the moderation effect of brand trust and controlling the effect of age and gender. The findings confirmed that openness to change is associated with perceived benefits and risks. Furthermore, perceived benefits and system trust are associated with purchase intentions, which are, in turn, associated with the propensity of believing and acting on fake news. The study presents several novel contributions to theory and practice. 相似文献
7.
Payment for ecosystem services schemes (PES) are lauded as a market-based solution to curtail deforestation and restore degraded ecosystems. However, PES programs often fail to conserve sites under strong long-term deforestation pressures. Underperformance, in part, is likely due to adverse selection. Spatial adverse selection occurs when landowners are more likely to enroll parcels with low deforestation pressure than parcels with high deforestation pressure. Temporal adverse selection arises when parcels are enrolled for short time periods. In both cases, financial resources are allocated without having a sizeable impact on long-term land use change. Improving program performance to overcome these shortcomings requires understanding attributes of landowners and their parcels across large scales to identify spatial and temporal enrollment patterns that drive adverse selection. In this paper, we examine these patterns in Argentina’s PES program in Chaco forest, a global deforestation hotspot. Our study area covers 252,319 km2. Results from multinomial logistic regression models showed that large parcels of enrolled land and parcels owned by absentee landowners exhibit greater evidence of spatiotemporal adverse selection than smaller parcels or parcels owned by local landowners. Furthermore, parcels managed under land use plans for conservation and restoration are more likely to be associated with adverse selection than parcels managed for financial returns such as harvest of non-timber forest products, silviculture, and silvopasture. However, prior to recommending that PES programs focus on land uses with higher potential earnings, a greater understanding is needed of the degree to which these land uses meet ecological and biodiversity goals of PES programs. We suggest that increased spatial targeting of enrollment, along with enrollment of local landowners and further incentives for land uses that support conservation and restoration, could promote long-term conservation of forest lands. 相似文献
8.
Mining has been necessary for human activities and is conducted in line with this need. The location of mines must sometimes be where land use overlaps with other activities because the location of the mined substance cannot be changed. In Turkey, forestland are the most common of these overlapping areas. Therefore, mining has frequently occurred on forestland in Turkey—and worldwide. After the mining operation activities are conducted, the forestland are rehabilitated and returned to the forest administration. The examination of used and returned areas provides an opportunity to create an optimal situation between “mining for sustainable development” and “protection of forestland.”Accordingly, several questions, such as mining production amounts, degrees of social and economic development of the cities in which enterprises are conducting mining, the quantity of the areas they used for mining activities in forestland, the areas which were returned to the forest administration, operating license areas and operation permit areas, and the life of mining operation, were asked to the mining enterprises in Turkey through the “Survey Monkey” program in 2018. Thus, according to mineral groups, different land use rates were compared with the operating license areas, and the land uses for each mineral group were analyzed by considering the operation activity periods. The results indicate that the sustainability of the use of forestry in mining activities in Turkey has changed in a positive direction, particularly because of changes in mining and environmental legislation in Turkey over the last decade. 相似文献
9.
《International Journal of Forecasting》2020,36(4):1517-1530
This paper develops indicators of unstructured press information by exploiting word vector representations. A model is trained using a corpus covering 90 years of Wall Street Journal content. The information content of the indicators is assessed through business cycle forecast exercises. The vector representations can learn meaningful word associations that are exploited to construct indicators of uncertainty. In-sample and out-of-sample forecast exercises show that the indicators contain valuable information regarding future economic activity. The combination of indices associated with different subjective states (e.g., uncertainty, fear, pessimism) results in further gains in information content. The documented performance is unmatched by previous dictionary-based word counting techniques proposed in the literature. 相似文献
10.
Adolescence constitutes the second and final window of human growth and a period of specific vulnerabilities, such as early pregnancy, early marriage, HIV infection, suicide, violence, alcohol, and drugs. Only a limited body of research investigates the effects of humanitarian crises on the human capital and well-being of adolescents. The evidence focuses on the short-term effects of conflict and, to a lesser extent, natural disasters on education, physical health, and nutrition, but not on mental health. Most analyses examine the situations of individuals exposed in utero and young childhood, but rarely during adolescence. Typically missing are robust empirical identification strategies and estimates on heterogeneous effects across age or gender. The lack of quality data and challenges in defining adolescence, establishing causality, or ensuring ethical research explain the knowledge gaps. Possible ways to expand the evidence base include mixing georeferenced data on individual location with georeferenced data on crises, sharpening quasi-experimental analytical techniques, and reconsidering the current timing of demographic data collection, now spanning 4- or 5-year intervals. The failure to make such adjustments will end by ignoring specific vulnerabilities among adolescents and render sustainable progress in well-being globally, narrowing inequalities, and guaranteeing human rights to all more difficult to achieve. 相似文献