1,720,986 research outputs found
Three essays on count data estimation methods with applications to health economics
Get PDFThe purpose of this dissertation is to propose and estimate count data microeconometric models that take into account special features of health care data. Three problems in health economics are investigated. The first essay analyzes the effect of managed care insurance plans on the demand for outpatient physician visits. It provides a Bayesian method to empirically separate selection effects due to individual choice of coverage and incentive effects known as moral hazard. The proposed Endogenous Hurdle Poisson log-Normal model addresses two important econometric issues: the large proportion of zero outpatient visits and the endogeneity of managed care insurance status to utilization of outpatient services. The data are obtained from the Medical Expenditure Panel Survey, (MEPS), and the sample consists of privately insured individuals, aged 21-64, all of whom are employed but not self-employed.The analysis indicates both favorable selection bias and important moral hazard effects in the decision whether to utilize an outpatient visit or not. The second essay investigates the impact of health insurance coverage on utilization of doctor visits. A Bayesian panel count data model with correlated random effects and endogenous treatment of the insurance variable is applied to a subset of the Health and Retirement Study (HRS), a national longitudinal survey of individuals over 50 years old and their spouses. The age limit for Medicare eligibility at age 65 serves as an exclusion restriction. After controlling for selection effects insured individuals present higher utilization of doctor visits. The third essay analyzes the demand for cigarettes using data from the 1994-1996 Continuing Survey of Food Intakes by Individuals (CSFII).Since individuals tend to round their consumption of cigarettes in packs smoked per day the dependent variable - number of cigarettes - exhibits pile-ups of counts. The mixed binary-ordered probit approach accommodates this feature of the data and models the starting smoking, the quitting smoking and the how much to smoke decisions. The analysis is performed separately for men and women and provides strong evidence of gender differences in cigarette consumption
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
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
U.S. demand for organic and conventional vegetables: a Bayesian censored system approach
Get PDFDemand for organic and conventional vegetables is investigated using data from A.C.
Nielsen’s 2006 Homescan panel. We use a Bayesian Markov chain Monte Carlo technique,
along with data augmentation, to estimate a large linear approximate Almost
Ideal Demand System with censored dependent variables. Demands are price elastic,
and expenditure elasticities are very high for organic vegetables, whilst demands for
conventional vegetables are primarily inelastic. We find a mix of gross substitution
and complementarity among the vegetable products, but net substitution is the dominant
pattern. Socio-demographic characteristics also play important roles in demands.
These findings can inform deliberations about marketing campaigns, nutrition education
and policy interventions
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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