1,720,954 research outputs found
Maisto ir mitybos saugumo duomenų spragų užpildymas: koks metodas yra geriausias Afrikos maisto ir mitybos saugumui?
No full textOur study presents the methods adopted to produce accurate imputed values for Africa\u27s food security and nutrition (FSN). We focused primarily on the following five imputation methods for handling missing data: Mean Imputation; Multiple Imputed values using a Chained Equation (MICE); imputation based on the Conditional Distribution of a variable Diagnostics (mi); Additive Regression and Predictive Mean Matching (Hmisc); and Random Forest (missForest). We describe each method, including how they performed under MAR and MNAR using RMSE and MAE as a measure of accuracy. After these methods of imputation were examined for nonignorable missing values in the context of accurate and unbiased estimates for food and security analysis, we found that MissForest handled nonignorable missing values more effectively and with less bias, increasing the precision of the data by imputing the closest data values within the dataset. Hence the missForest is the best alternative for handling missing values for food security and nutrition concerning Africa. This study adds to the current body of knowledge on food and nutrition insecurity and provides useful information to policymakers, particularly about the imputations of missing values aimed at food security and nutrition concerning Africa, which has significant economic and social ramifications.Šiame tyrime pristatomi metodai, naudojami siekiant parinkti tikslesnes procedūras priskiriant reikš\-mes trūkstamiems Afrikos maisto saugumo ir mitybos (MSM) duomenims. Pagrindinis dėmesys skiriamas šiems penkiems trūkstamųjų reikšmių duomenyse priskyrimo metodams: vidurkio priskyrimas; kartotinis priskyrimas naudojant grandininę lygtį (Multiple Imputation using a Chained Equation, MICE); priskyrimas su diagnostika, pagrįstas kintamojo sąlyginiu skirstiniu (mi); adityvioji regresija ir vidurkio prognozės atitikimas (Hmisc); bei priskyrimas naudojant atsitiktinius miškus (MissForest). Aprašant kiekvieną metodą aptariama, kaip jis veikė atsitiktinai trūkstamųjų (Missing At Random, MAR) ir neatsitiktinai trūkstamųjų (Missing Not At Random, MNAR) reikšmių atvejais naudojant vidutinės kvadratinės paklaidos kvadratinę šaknį ir vidutinę absoliučiąją paklaidą kaip tikslumo matą. Ištyrus, ar nėra įvertinių tikslumo ir nepaslinktumo prasme MSM analizėje neignoruotinų trūkstamųjų reikšmių, buvo nustatatyta, kad MissForest metodas efektyviau ir su mažesniu poslinkiu priskyrė trūkstamąsias reikšmes tuo pagerindamas duomenų kokybę. Vadinasi, MissForest metodas yra tinkamiausia alternatyva Afrikos MSM duomenų trūkstamosioms reikšmėms priskirti. Šis tyrimas papildo dabartines žinias apie maisto ir mitybos nesaugumą ir suteikia naudingos informacijos politikos formuotojams, ypač apie galimas trūkstamųjų reikšmių priskyrimo MSM duomenyse ekonomines ir socialines pasekmes Afrikoje
Didelį maisto stygių Afrikoje nusakantys veiksniai naudojant ilgalaikį Puasono apibendrintąjį mišrųjį modelį
No full textFood insecurity is a multifaceted issue (challenge) that affects health care, policies, agriculture output leadership, the environment, the food system, and the politics of global commerce in the food industry. Our aim was to get the relevant components of food security and nutrition concerning Africa holistically and use these identified components to discover the most informative correlates that affect the number of severe food insecure individuals in Africa with its population as an offset. Principal Component Analysis (PCA) was used to detect the relevant components of Africa’s food security and nutrition. The Poisson Generalized Linear Mixed Model (GLMM) was employed to identify the significant components. Generalized estimating equations were then applied to account for the overdispersion associated with the Poisson distribution. To make the interpretation of the results more meaningful, 10 PCA components were selected. They explained 74.6\% of the variation within the data. The GLMM analysis remarkably identified Nutrient Intake, Average Food Supplied, Child Care, Dietary Supply Adequacy, and Feeding Practices Among Infants to be significantly associated with the Rate of Severe Food Insecure Individuals (p-value < 0.05). A better improvement in the average food supply in Africa is likely to yield an improvement in food security and nutrition. Our findings provide insight concerning Africa which will help policymakers create targeted plans for Africa that will address issues with food security and nutrition, and this will fuel the achievement of Sustainable Development Goal 2.Maisto stygius yra daugialypė problema (iššūkis), turinti įtakos sveikatos priežiūrai, politikai, žemės ūkio produkcijos lyderystei, aplinkai, maisto sistemai ir pasaulinės prekybos maisto pramonėje politikai. Mūsų tikslas buvo nustatyti svarbius aprūpinimo maistu ir mitybos veiksnius, kompleksiškai susijusius su Afrika, ir panaudoti šiuos nustatytus veiksnius, kad atrastume informatyviausius koreliatus, kurie įtakoja badaujančiųjų (maisto nepriteklių patiriančių asmenų) skaičių Afrikoje ir jos gyventojus kaip atsvarą. Pagrindinių komponenčių analizė (PKA) buvo naudojama siekiant surasti minėtus svarbius Afrikos aprūpinimo maistu ir mitybos veiksnius. Reikšmingiems veiksniams nustatyti buvo naudojamas Puasono apibendrintasis tiesinis mišrusis modelis (ATMM). Tada buvo taikomos apibendrintosios įvertinimo lygtys, kad būtų atsižvelgta į perteklinę dispersiją, susijusią su Puasono skirstiniu. Kad rezultatų interpretacija būtų prasmingesnė, buvo pasirinktos 10 PKA komponenčių. Jos paaiškino 74,6\% duomenų variacijos. ATMM analizė parodė, kad maistinių medžiagų suvartojimas, vidutinis tiekiamas maistas, vaikų priežiūra, mitybos tiekimo pakankamumas ir kūdikių maitinimo praktika yra statistiškai reikšmingai susiję su maisto nepriteklių patiriančių (badaujančių) asmenų skaičiumi (p reikšmė < 0,05). Tikėtina, kad pagerinus vidutinę maisto pasiūlą Afrikoje, pagerės aprūpinimas maistu ir mityba. Mūsų išvadose pateikiama įžvalgų apie Afriką, kurios padės politikos formuotojams parengti Afrikai skirtus tikslinius planus, kuriuose bus sprendžiami aprūpinimo maistu ir mitybos klausimai, o tai padės siekti 2-ojo darnaus vystymosi tikslo
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
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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