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41.
We introduce a class of semiparametric time series models (SemiParTS) driven by a latent factor process. The proposed SemiParTS class is flexible because, given the latent process, only the conditional mean and variance of the time series are specified. These are the primary features of SemiParTS: (i) no parametric form is assumed for the conditional distribution of the time series given the latent process; (ii) it is suitable for a wide range of data: non-negative, count, bounded, binary, and real-valued time series; (iii) it does not constrain the dispersion parameter to be known. The quasi-likelihood inference is employed in order to estimate the parameters in the mean function. Here, we derive explicit expressions for the marginal moments and for the autocorrelation function of the time series process so that a method of moments can be employed to estimate the dispersion parameter and also the parameters related to the latent process. Simulated results that aim to check the proposed estimation procedure are presented. Forecasting procedures are proposed and evaluated in simulated and real data. Analyses of the number of admissions in a hospital due to asthma and a total insolation time series illustrate the potential for practical situations that involve the proposed models.  相似文献   
42.
The objective of the paper is to determine if the futures prices of hard red spring wheat (HRSW) have stabilizing or destabilizing impact on spot HRSW price in North America. Several important results emerge from thorough empirical analysis. First, both Granger causality tests and directed acyclic graph algorithms (DAGs) point to two-way causality between futures and spot HRSW prices and thus endogeneity in both prices formation. To the contrary, both procedures suggest that ending stocks are exogenous to spot and futures HRSW prices. Both vector error correction model and impulse response functions point to a large and long-lasting impact of a shock to futures price on spot price level. Finally, variance decomposition analysis indicates that futures prices are responsible for the bulk of spot price volatility in both short and long run. Our result is consistent with those of theoretical models suggesting that when production (supply side) is the dominant disturbance, spot price is destabilized in both the short and the long run by futures prices. An important implication of this research is the need for alternative market mechanisms or alternative farm policy measures that would mitigate price risk and ensure sustainable farming of American HRSW farmers.  相似文献   
43.
This paper analyzes the effect of lifting primary school fees on educational attainment in Uganda. After the abolishment of school fees in 1997, the enrollment rate more than doubled. Two decades later, we know little about the effect of the policy on educational attainment. With recent data on eight cohorts exposed to free education, we analyze the impact of the policy on years of completed primary school, completion of primary school, and transitioning to secondary school. We use a straightforward regression analysis with cohort dummies and household fixed effects to control for unobserved heterogeneity. We find that lifting school fees had no effect on the years of primary school achievement and the likelihood of primary school completion. We find some weak evidence that the likelihood of those who completed primary education to start secondary school increased after Universal Primary Education.  相似文献   
44.
加强民营企业党员教育工作,对增强党的阶级基础、扩大党的群众基础、巩固党的执政基础具有十分重要的意义。做好党的宗旨和企业宗旨相结合、企业党建活动与生产运营活动相结合、党课内容革新与企业文化建立相结合,不仅能加强民营企业基层党组织建设,而且能促进民营企业又好又快发展。  相似文献   
45.
The number of Irish dairy farms with herds greater than 100 cows has increased from 4.5 % in 2005 to 23 % in 2016. The abolition of the dairy quota in 2015 has led to predictions that this trend will continue and that an additional 6000 people will be required to work on dairy farms by 2025. Ownership of farms is esteemed, with farm employment perceived as a poor second option, so it is necessary to identify possible routes towards creating 'good' farm employment relationships. This paper explores the social, cultural and economic values of employers and employees in the context of early experiences of farm employment in post-quota Ireland. Using narrative analysis, this study found that employees gained esteem and pride from acquiring managerial responsibilities and receiving recognition for their abilities and accomplishments from their employers. Greater social recognition of employ’ abilities by peer groups and in networks (social capital) cemented ‘good employee’ status. Employers, in a context of unprecedented dairy production expansion, emphasised the need for and demonstrated changing of power structures to open up the farm to new forms of influence. However, employers’ reflexivity in support of employment relationships was undermined overall by what the management literature calls a weak ‘rewards system’ for employees. Without the supportive scaffolding of a formalised rewards system, relational gestures of responsibility-devolution and employ’ appreciation of employees may be insufficient to sustain quality farm management employment in the long term. Inevitably, this diminishes the attractiveness of farm employment, limiting the drawing of talent not only into farm employment but into associated capacity-building programmes.  相似文献   
46.
While there is a prevailing rich body of studies on the role of university knowledge transfer office (KTO) in the commercialization process as part of the Third Mission, research on its role in community engagement activities is relatively neglected, even as funding agencies and policy makers conceive these as instrumental to sustaining social and economic development. This article focuses on the role of university KTO in supporting, facilitating or undertaking Third Mission community engagement activities. Drawing on data from the annual Higher Education Business and Community Interaction survey for the years 2007–2012, this paper empirically explores the relationship between a range of Third Mission activities by university KTO and performance of three key business-community services – provision of consultancy, provision of continuous professional development courses (CPD), and leasing of facilities and equipment (FE). It emerges that the routines of developing strategic plan and creating spin-off are positively associated with all types of community knowledge transfer (CKT) activities. Further, the routines of establishing partnerships with local and regional bodies, and licensing are positively related to CPD and FE, respectively. The article is concluded with implications for theory, practice, policy, and suggestions for future research.  相似文献   
47.
We participated in the M4 competition for time series forecasting and here describe our methods for forecasting daily time series. We used an ensemble of five statistical forecasting methods and a method that we refer to as the correlator. Our retrospective analysis using the ground truth values published by the M4 organisers after the competition demonstrates that the correlator was responsible for most of our gains over the naïve constant forecasting method. We identify data leakage as one reason for its success, due partly to test data selected from different time intervals, and partly to quality issues with the original time series. We suggest that future forecasting competitions should provide actual dates for the time series so that some of these leakages could be avoided by participants.  相似文献   
48.
Many regions on earth face daily limitations in the quantity and quality of the water resources available. As a result, it is necessary to implement reliable methodologies for water consumption forecasting that will enable the better management and planning of water resources. This research analyses, for the first time, a large database containing data from 2 million water meters in 274 unique postal codes, in one of the most densely populated areas of Europe, which faces issues of droughts and overconsumption in the hot summer months. Using the R programming language, we built and tested three alternative forecasting methodologies, employing univariate forecasting techniques including a machine-learning algorithm, with very promising results.  相似文献   
49.
This paper estimates a three-frequency dynamic factor model for nowcasting the Canadian provincial gross domestic product (GDP). The Canadian provincial GDP at market prices is released by Statistics Canada annually with a significant lag (11 months). This necessitates a mixed-frequency approach that can process timely monthly data, the quarterly national accounts, and the annual target variable. The model is estimated on a wide set of provincial, national and international data. In a pseudo real-time exercise, we find that the model outperforms simple benchmarks and is competitive with more sophisticated mixed-frequency approaches (MIDAS models). We also find that variables from the Labour Force Survey are important predictors of real activity. This paper expands previous work that has documented the importance of foreign variables for nowcasting Canadian GDP. This paper finds that including national and foreign predictors is useful for Ontario, while worsening the nowcast performance for smaller provinces.  相似文献   
50.
In contemporary African cities, dressing well and wearing exclusive garments has become crucial for people in search of identity, distinction and individuality. The research presented in this article, situated at disciplinary intersections of cultural studies, fashion practices and sustainability, provides a case study of African tailors conducted in Maputo and Lisbon, with a special focus on identity building of African immigrants in Portugal. However, the role of tailors in this acculturation process has been ignored in the consumption approach to creative cities. This study is therefore also a reaction to the mainly Western world of regular couture, and to ‘creative city materials’ that focus on consumption. Instead, we emphasize the importance of African tailors who de facto shape urban experiences—visually incrementing practices—that are fundamental to the comprehension of sartorial culture, while we also allude to the complex intersections between local and global markets. In the first part of this article we describe a semi-ethnographic study among tailors in Maputo and Lisbon. The second part presents a participatory action approach that entailed developing an educational programme for African tailors where culture and creativity meet. This programme empowered tailors to tap into their cultural knowledge on tailoring and their awareness of community identity. In our study we argue that the idea of creative cities and their creative economy should be approached from a cultural perspective, by building awareness of the importance of local creative classes instead of focusing on importing those classes.  相似文献   
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