1,721,056 research outputs found
The Effect of Insurance on Farmers' Production, Technical Efficiency and Input Use: An Endogenous Stochastic Frontier Model to Analyse the Italian Case
Full text linkThe presence of risk in the agricultural sector has important implications for production decision-making and, therefore, the economic and environmental performance of farms. Given the risky environment, the EU policymakers introduced several risk management tools aimed at the reduction of the income variability of farms. The adoption of risk management tools impacts production decision-making in several ways. Therefore, analysing the interrelation between farm performances and risk management tools is crucial for policymakers to foster both the economic and environmental sustainability of farming.
Despite the significant role of risk and risk management tools in agricultural production decisions, most studies on farm-level performance analysis do not account for them. Moreover, when included, it is usually assumed that risk and risk management tools are independent of the error terms in the model. Therefore, endogeneity issues are often not considered, which could overstate or understate the effect of risk and risk management tools on farm performance. Indeed, producers may modify input use in response to observed adverse events resulting in a correlation between inputs and statistical error. In addition, endogeneity may arise when including the risk management tools. The model misspecifications due to the absence of endogeneity treatment may lead to erroneous inferences about the estimates of input elasticities, economies of scale, and inaccurate estimates of technical efficiency. Consequently, the analysis may lead to incorrect interpretation and, ultimately, to wrong policy advice.
Among the risk management tools, crop insurance represented the most funded instrument in the EU. In spite of recent growth in the scientific literature on crop insurance in agricultural economics, only a few studies have concentrated on the effects of crop insurance expenditure on farm outcomes. Specifically, the impact of insurance on productivity and technical efficiency has received scant consideration. Therefore, the general objective of this thesis is to quantitatively assess the effect of crop insurance on input use, productivity, and technical efficiency of Italian farming producers. In particular, this thesis examines whether insurance adoption could reduce farmers' inefficient input use that results from the uncertainty of the results. Grape farming has been selected as a case study since it is the sector where crop insurance has been most adopted in Italy. The novelty of this research relates to the inclusion of crop insurance adoption endogeneity into the stochastic frontier approach, allowing for the estimation of parameters with a higher degree of accuracy.
The thesis is divided into seven chapters. Each chapter attempts to lay the groundwork for answering the research question. In particular, Chapter 1 introduces the background, the problem, and the research question, while Chapter 2 introduces the Italian crop insurance regulations and the spread of subsidized crop insurance in the grape-producing sector.
Chapter 3 describes the theoretical background. Specifically, the production function is introduced, which is the first step to comparing the performance of producers. Subsequently, productivity, technical efficiency, and their difference are discussed. Following that, the optimal input use and the effects of risk-aversion on production choice have been discussed. Finally, the impact of insurance on farm performance has been reviewed. In particular, the dilemma which regards the re-optimization or the moral hazard effects arising from the insurance adoption has been investigated.
Then, Chapter 4 is based on an in-depth literature review on farm productivity and efficiency, which has been conducted using a scoping review methodology, focusing on studies that have included risk and risk management tools within the stochastic frontier analysis. The main contribution of the review relates to the indication of a literature gap concerning studies accounting for endogeneity and the clarification of methods used to account for it by using a risk-accommodating stochastic frontier approach. Despite the increasing methodologies proposed in the literature to deal with endogeneity, only a few studies have treated it in farm risk-performance evaluations when using the stochastic frontier analysis. According to the findings of the review presented in Chapter 4, it can be concluded that there is a literature gap regarding the adoption of a comprehensive approach capable of dealing with endogeneity when assessing farm productivity/technical efficiency and risk. Neglecting endogeneity in these analyses may lead to biased estimates and, thus, distorted policy recommendations. Endogeneity and risk issues need to be concurrently addressed to make strides in achieving economic and environmental sustainability. The comprehensive approach could help to achieve more accurate estimates that could yield recommendations that ensure improved productivity and technical efficiency of farmers.
Bearing in mind that, a case study has been implemented to assess how insurance affects Italian specialized-quality grape growers' production, technical efficiency, and input use while accounting for the endogeneity of the crop insurance adoption. Therefore, a panel instrumental variable stochastic frontier approach is applied over the years from 2008 to 2017 using data from the Farm Accountancy Data Network. The methodology, the econometric strategy to deal with endogeneity, the dataset, and the model specification are presented in Chapter 5, while the case study is documented in Chapter 6.
The findings highlight the need to account for endogeneity brought on by the adoption of insurance. Moreover, it was found that crop insurance increases output and efficiency while decreasing the need for intermediate inputs in Italian grape farming. It implies that insurance assists in reducing the suboptimal input use caused by risk-aversion and the uncertainty of farming outcomes.
Finally, Chapter 7 discuss the results, summarizes the main conclusion of the thesis, and highlights the limitations and future research directions
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
POWER PATTERN SYNTHESIS OF RECONFIGURABLE SHAPED-BEAM REFLECTARRAYS
No full textIn this paper, the design of an electronically reconfigurable shaped-beam reflectarray is presented for the first time. The design technique is based on a flexible, efficient and effective synthesis algorithm, which evaluate the design parameters from the far-field power pattern specifications. The electronic control of the pattern has been realized by integrating varactor diodes within the array elements. The synthesis algorithm amounts to find their biasing voltages. The numerical analysis proves the effectiveness of the approach
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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