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1.
The COVID-19 pandemic has had a great impact on food shopping behavior. However, changes in food shopping behavior and related decision-making mechanisms remain unexplored. This study conducted a face-to-face questionnaire survey with 900 residents in three communities in Haidian, Beijing, China, to analyze food shopping behavior during the periods of pre-lockdown, lockdown (January–March 2020), and post-lockdown. Our results indicated that the preference for fresh food e-commerce shopping was accelerated by the lockdown with the usage rate increasing by 48%; the wet markets were seriously hit by the lockdown policy and had not fully recovered by the post-lockdown period (with a 75% reduction in the usage rate during lockdown). The psychological mechanisms of changes in food shopping behavior revealed that the context (e.g., community facilities) and the perceived risk of COVID-19 were two significant factors impacting the four shopping choices investigated. Specifically, the context factors affected behavior directly for supermarkets and convenience stores and indirectly for e-commerce and wet markets. The findings are expected to help in guiding emergency responses during a future pandemic as well as the long-term construction of food supply facilities.  相似文献   
2.
Instructional Manipulation Checks (IMCs) assess respondent behavior by, for example, asking participants not to answer a trick question. We find IMCs can be used to detect problematic response behavior in longitudinal surveys. This is important because a Latent Class Analysis based on IMC-failure in the two reported studies reveals that between 9% and 12% of respondents can be labelled Inattentive Stayers at the first survey-wave and between 13% and 17% at the third wave. The tendency of Inattentive Stayers to remain in the panel is particularly relevant for online panel services such as MTurk, with workers participating in many surveys over longer time-periods. We find IMC-failure to be mitigated by a warning to respondents that their attention will be checked early in the survey, but not by repeated exposure to IMCs, or a timer leaving questions on the screen longer. Respondent personality also plays a role in IMC-failure, which implies persistency of undesirable respondent behavior.  相似文献   
3.
ABSTRACT

This study discusses how to apply counseling-learning (CL) principles to a particular e-learning solution for teaching a tourism-related subject via a massive open online course (MOOC). Several effective caring patterns in achieving learning-related goals and being part of a community according to the CL principles are presented and discussed using the MOOC “eTourism: Communication Perspectives” as a case study. The study underlines how the MOOC platform can act as a place for contents enjoinment and active learning. Moreover, the active role of social media for increasing the engagement of learners in the proposed activities and for developing a sense of the community is identified. In particular, Facebook and Twitter can act as places for community building and informal social interactions among learners that last beyond the completion of the course, which in turn can be a valid aid for continuing the relationships among instructors/learners and learners/learners, and for reaching new ones.  相似文献   
4.
In the early 1980s, disease susceptibility in short-season lentil landraces began to limit productivity in areas where relay cropping took place in Bangladesh. Since then, several improved high-yielding lentil varieties, which are resistant to rust and blight and suitable in the relay cropping system, have been released jointly by national and international research centers. This study used three methods, namely a panel of experts, a survey of 1000 households where the respondents named the variety they used, and DNA fingerprinting of seed samples collected from all lentil plots cultivated by survey households to estimate adoption. Double hurdle and instrumental variables regression methods were applied to the household survey and DNA fingerprinting data to identify determinants of adoption and measure their impacts. Of particular interest was whether estimates of adoption, determinants of adoption and impacts varied by method of variety identification. Results showed that the expert panel overestimated the adoption of more recent varieties while about 89% of the farmer-reported varieties were accurate, as verified by DNA fingerprinting. DNA fingerprinting appears to have little advantage for estimating the level of adoption in this case, where few varieties of lentils are found, local variety names do not exist, and most seed is obtained through a formal system. However, even under these conditions, determinants of adoption vary by identification method, and use of farmer-reported information on the variety can lead to erroneous conclusions about determinants of adoption. Because recent breeding efforts have focused on taste and cooking considerations, yield impacts were not significantly different from zero.  相似文献   
5.
在这个网络社会愈发深化的时代,通过互联网科技完善和发展线上供应链金融成为必要的发展方向。本文首先梳理了传统供应链金融的基本模式,发现了其存在的不足;然后重点介绍了当前三种主要的线上供应链金融模式,总结了线上供应链金融的优势;最后,提出相关政策建议,认为金融机构应该不断升级线上供应链金融产品,逐步完善供应链金融线上操作系统,监管机构需要出台更加严格的监管规则对线上供应链金融进行有效监管。  相似文献   
6.
研究目的:基于全国典型村庄调研,分析不同地区农村宅基地闲置程度和成因,为农村宅基地集约利用和乡村振兴提供建议。研究方法:实地调研法、对比分析法。研究结果:(1)调研村庄宅基地闲置现象普遍,2018年闲置程度平均为10.7%。(2)各地村庄宅基地闲置程度差异明显。分区域看,东部村庄宅基地闲置程度最高,中部村庄最低;分城乡区位看,村庄离城市距离越远,宅基地闲置程度越高;分地形看,平原村庄宅基地闲置程度最高;分是否为贫困村庄看,村庄宅基地闲置程度随村庄贫困程度的加深而升高。(3)宅基地闲置是乡村人口结构变化与宅基地利用失衡的结果。长期外出务工、城镇有住房、“一户多宅”、宅基地损毁引起宅基地闲置的成因占比依次下降。(4)农村宅基地闲置受乡村地域内外宏微观因素综合影响,经济增长和城镇化引起的就业非农化、人口市民化是宅基地闲置的直接动因,现行城乡二元制度和宅基地管理制度是宅基地闲置的根本原因。研究结论:盘活利用农村闲置宅基地,需要因地制宜推动闲置宅基地整治利用、健全宅基地有偿使用和退出机制、创新城乡制度加快农业转移人口市民化。  相似文献   
7.
ABSTRACT

CouchSurfing is a free social-network-based online hospitality exchange network, aptly representing a new sharing economy phenomenon. Based on social capital theory and previous literature, this study attempts to answer why hosts help strangers without any expected economic benefit within online hospitality exchange networks. An empirical study based on a Web survey conducted with CouchSurfing hosts reveals that the most identified antecedents (enjoy helping, shared narratives, desire to make friends, and reciprocity) are significantly related to hosts’ intention to share accommodations. Interestingly, the overshadowing effect of trust in CouchSurfing on the intention to share accommodations is also found.  相似文献   
8.
The purpose of this article is to measure the efficiency of hotel units in Romania from the customers’ point of view and to identify factors that explain the differences in efficiency between hotel units. A stochastic production frontier is estimated together with a technical inefficiency model using cross-sectional data from 622 hotel units in Romania. The results show that the average efficiency is high. However, there are significant differences between hotels in different regions and with different star ratings. The most influential factor affecting efficiency is the online visibility of a hotel unit on social media platforms and on travel planning sites. The study’s results offer insight for hotel decision-makers to be able to improve the perception of hotel efficiency by taking appropriate action to meet customer needs.  相似文献   
9.
将K-means聚类算法应用到无线局域网(WLAN)位置指纹定位中,虽然可以缩短定位时间,但是容易降低定位精度。为了解决此问题,提出了基于改进指纹聚类的WLAN定位优化方法。首先根据接收信号强度标准差来优化初始聚类中心的选取,然后对指纹数据进行聚类处理,最后进行在线定位。实验结果表明,与传统的WLAN位置指纹定位方法和K-means聚类定位方法相比,基于改进指纹聚类的定位优化方法不仅缩短了定位时间,还能有效提高定位精度。  相似文献   
10.
利用1 790份网络调查问卷数据,采用相关分析、交叉分析等统计方法,研究网购食品消费者选择行为,分析网购食品市场渗透率不高、用户黏性不足的主要原因,结果表明,消费者个性特征差异会导致对网购食品的不同态度,进而影响消费者对网购食品的选择行为;良好的网购环境、物美价廉的食品、优质的网购服务,是促使消费者选择网购食品的主要因素,对网购食品安全的担忧、习惯于传统购物方式、网购维权难度大,是抑制消费者选择网购食品的主要因素,尤其是网购食品"难维权、维权难"可能会放大消费者对网购食品产生的消极态度。为此,应加强网购食品多主体协同监管,消除消费者怀疑心理和不放心态度;建立以消费者需求为中心的网购食品质量安全供应链管理体系,推动线上市场和线下实体店紧密结合、融合发展;完善网购食品维权制度,畅通维权渠道。  相似文献   
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