1,721,052 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
“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
Methicillin-resistant Staphylococcus Aureus in Canadian Hospitals from 1995 to 2007: A Comparison of Adult and Pediatric Inpatients
The literature directly comparing the epidemiology of MRSA among adult and pediatric hospitalized patients is strikingly minimal. The objective of this thesis was to identify any differences between these two patient groups. The Canadian Nosocomial Infections Surveillance Program MRSA data (1995 to 2007: n=1,262 pediatric and 35,907 adult cases) were used to compare MRSA clinical and molecular characteristics and rates. Hospital characteristics were modeled using repeated measures Poisson regressions. The molecular and epidemiological characteristics of MRSA differed significantly between adults and children. Compared to children, MRSA in adults was more likely to be healthcare-associated, colonization, SCCmec type II, PVL negative, and resistant to most antibiotics. Rates of MRSA in Canada increased in both populations over time but were significantly higher in adults. The hospital characteristics associated with increased MRSA rates differed in adult and pediatric facilities. Implications for infection prevention and control strategies are discussed
Appropriate Similarity Measures for Author Cocitation Analysis
We 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
Assessing Parameter Importance in Decision Models. Application to Health Economic Evaluations
Background: Uncertainty in parameters is present in many risk assessment and decision making problems and leads to uncertainty in model predictions. Therefore an analysis of the degree of uncertainty around the model inputs is often needed. Importance analysis involves use of quantitative methods aiming at identifying the contribution of uncertain input model parameters to output uncertainty. Expected value of partial perfect information (EVPPI) measure is a current gold- standard technique for measuring parameters importance in health economics models. The current standard approach of estimating EVPPI through performing double Monte Carlo simulation (MCS) can be associated with a long run time. Objective: To investigate different importance analysis techniques with an aim to find alternative technique with shorter run time that will identify parameters with greatest contribution to uncertainty in model output. Methods: A health economics model was updated and served as a tool to implement various importance analysis techniques. Twelve alternative techniques were applied: rank correlation analysis, contribution to variance analysis, mutual information analysis, dominance analysis, regression analysis, analysis of elasticity, ANCOVA, maximum separation distances analysis, sequential bifurcation, double MCS EVPPI,EVPPI-quadrature and EVPPI- single method. Results: Among all these techniques, the dominance measure resulted with the closest correlated calibrated scores when compared with EVPPI calibrated scores. Performing a dominance analysis as a screening method to identify subgroup of parameters as candidates for being most important parameters and subsequently only performing EVPPI analysis on the selected parameters will reduce the overall run time
A Systematic Review of Common Drug Review Pharmacoeconomic Submissions and an Analysis of Emerging Trends
Given financial constraints, drug manufacturers are required to provide pharmacoeconomic evaluations to demonstrate the value for money of their drug compared to current treatment when requesting reimbursement by publicly funded health care systems. This thesis is a retrospective examination of pharmacoeconomic evaluations submitted for review to the Common Drug Review process. Its purpose was to determine the pattern of adherence to guidelines, trends in methodological quality, and transparency, changes in the adoption and practice of sensitivity analysis and probabilistic methods, use of indirect treatment comparison, and identify methodological factors−determinants of recommendations. Using an instrument that was developed and tested, information from 201 pharmacoeconomic evaluations was collected and analysed. Pharmacoeconomic evaluations may have improved over time in terms of adherence, methodological quality, transparency, use of probabilistic sensitivity analysis and indirect treatment comparison. However, such improvements have been minimal and further efforts are needed to better improve pharmacoeconomic evaluations in the future
Methicillin-resistant Staphylococcus Aureus in Canadian Hospitals from 1995 to 2007: A Comparison of Adult and Pediatric Inpatients
The literature directly comparing the epidemiology of MRSA among adult and pediatric hospitalized patients is strikingly minimal. The objective of this thesis was to identify any differences between these two patient groups. The Canadian Nosocomial Infections Surveillance Program MRSA data (1995 to 2007: n=1,262 pediatric and 35,907 adult cases) were used to compare MRSA clinical and molecular characteristics and rates. Hospital characteristics were modeled using repeated measures Poisson regressions. The molecular and epidemiological characteristics of MRSA differed significantly between adults and children. Compared to children, MRSA in adults was more likely to be healthcare-associated, colonization, SCCmec type II, PVL negative, and resistant to most antibiotics. Rates of MRSA in Canada increased in both populations over time but were significantly higher in adults. The hospital characteristics associated with increased MRSA rates differed in adult and pediatric facilities. Implications for infection prevention and control strategies are discussed
A Systematic Review of Common Drug Review Pharmacoeconomic Submissions and an Analysis of Emerging Trends
Given financial constraints, drug manufacturers are required to provide pharmacoeconomic evaluations to demonstrate the value for money of their drug compared to current treatment when requesting reimbursement by publicly funded health care systems. This thesis is a retrospective examination of pharmacoeconomic evaluations submitted for review to the Common Drug Review process. Its purpose was to determine the pattern of adherence to guidelines, trends in methodological quality, and transparency, changes in the adoption and practice of sensitivity analysis and probabilistic methods, use of indirect treatment comparison, and identify methodological factors−determinants of recommendations. Using an instrument that was developed and tested, information from 201 pharmacoeconomic evaluations was collected and analysed. Pharmacoeconomic evaluations may have improved over time in terms of adherence, methodological quality, transparency, use of probabilistic sensitivity analysis and indirect treatment comparison. However, such improvements have been minimal and further efforts are needed to better improve pharmacoeconomic evaluations in the future
Assessing Parameter Importance in Decision Models. Application to Health Economic Evaluations
Background: Uncertainty in parameters is present in many risk assessment and decision making problems and leads to uncertainty in model predictions. Therefore an analysis of the degree of uncertainty around the model inputs is often needed. Importance analysis involves use of quantitative methods aiming at identifying the contribution of uncertain input model parameters to output uncertainty. Expected value of partial perfect information (EVPPI) measure is a current gold- standard technique for measuring parameters importance in health economics models. The current standard approach of estimating EVPPI through performing double Monte Carlo simulation (MCS) can be associated with a long run time. Objective: To investigate different importance analysis techniques with an aim to find alternative technique with shorter run time that will identify parameters with greatest contribution to uncertainty in model output. Methods: A health economics model was updated and served as a tool to implement various importance analysis techniques. Twelve alternative techniques were applied: rank correlation analysis, contribution to variance analysis, mutual information analysis, dominance analysis, regression analysis, analysis of elasticity, ANCOVA, maximum separation distances analysis, sequential bifurcation, double MCS EVPPI,EVPPI-quadrature and EVPPI- single method. Results: Among all these techniques, the dominance measure resulted with the closest correlated calibrated scores when compared with EVPPI calibrated scores. Performing a dominance analysis as a screening method to identify subgroup of parameters as candidates for being most important parameters and subsequently only performing EVPPI analysis on the selected parameters will reduce the overall run time
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