1,720,956 research outputs found
The economics of climate change vulnerability, adaptation and mitigation in Tanzania
No full textIncludes bibliographical references.In Sub-Saharan Africa, climate change is set to hit the agricultural sector the most severely and cause suffering particularly for smallholder farmers. To cushion themselves against potential welfare losses, smallholder farmers need to recognize the changes already taking place in their climate and undertake appropriate investments in adaptation. This study investigates whether these smallholder farmers in Tanzania recognize climate change and, consequently, adapt to it in their agricultural activities. The study also investigates the factors influencing their choice of adaptation methods. In order to achieve this, the study analysed data from 534 randomly selected households in a sample of districts representing the six of the seven agro-ecological regions of the country. The data shows that Tanzanian smallholder farmers have observed changes in mean and variance precipitation and temperature and responded to it. The farmers have generally used short-season crops, drought-resistant crops, irrigation, changing planting dates and tree planting to adapt to the negative impacts of climate change on their agricultural yields. In this study, selection bias is corrected using a Heckman sample selection model. A binary probit model is used as a selection equation to investigate the factors influencing a farmer’s decision to undertake any adaptation at all to climate change while a multinomial probit model is used as an outcome equation to investigate the factors influencing farmers’ choice of specific adaptation methods. The inverse Mill’s ratio reported selection bias in choosing three of the adaptation methods. The findings of the study suggest that the Tanzanian government needs to assist smallholder farmers overcome the constraints they face in their attempts to adapt. The government can play a significant role by promoting adaptation methods appropriate for particular circumstances e.g. particular crops for different agro-ecological zones
Challenges and opportunities of climate change adaptation strategies among smallholder horticultural farmers in rural Tanzania
No full textAdapting to climate change is critical for smallholder farmers, as it directly influences agricultural productivity and livelihood security. While previous studies in sub-Saharan Africa and Tanzania have documented various coping measures, they often overlook the intersection of demographic differences, perceived opportunities, and barriers among smallholder horticultural farmers. This study examined challenges and opportunities of climate change adaptation strategies among such farmers in Mbeya, Tanzania. An exploratory qualitative design was applied, using focus group discussions and semi-structured interviews with 50 purposively selected farmers to explore their understanding, adaptation practices, and constraints. Findings show that understanding of climate change varied, with farmer organization leaders exhibiting broader, more inclusive knowledge. Key adaptation strategies included adopting climate-resilient crop varieties, improving water management through drip irrigation and rainwater harvesting, and diversifying income via high-value crops and off-farm activities. Demographic differences shaped approaches: female adults prioritized social and financial measures, such as savings groups, crop insurance, and peer learning; male adults focused on resource-intensive practices like large-scale water harvesting and soil fertility management; youths pursued innovative measures including the use of weather forecasts, access to microloans, and cultivation of fast-maturing crops. However, women faced financial and knowledge gaps; men encountered poor infrastructure and limited markets; and youths struggled with institutional barriers and insufficient climate information. The study recommends inclusive policies that enhance affordable finance, strengthen rural infrastructure, address institutional gaps, remove social and cultural barriers, and improve extension services to deliver timely climate information. These measures can strengthen smallholder resilience and sustain livelihoods amid increasing climate risks
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
- …
