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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
Homogeneity, Returns to Scale and (Log)Concavity
No full textThis brief note shows that if a production function, f, is quasiconcave, increasing and homogeneous, then f is concave if it displays nonincreasing returns to scale, and f is logconcave if it displays increasing returns to scale
Income Elasticities Without Parameters
No full textThis paper proposes a simple non-parametric framework to calculate income elasticities from a data set of observed prices and consumed quantities without having to estimate any parameters. The framework can be applied when the price-quantity data satisfies a revealed preference axiom called the strong version of the strong axiom of revealed preference (SSARP). The framework is used to calculate income elasticities for food and non-alcoholic drinks from a rich panel of household expenditures. For this category, it is found that households are rather homogeneous in their demand responses
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
A Monte Carlo Study of the Necessary and Sufficienct Conditions for Weak Separability
No full textWeak separability is an important concept in many fields of economic theory. This chapter uses Monte Carlo experiments to investigate the performance of newly developed nonparametric revealed preference tests for weak separability. A main finding is that the bias of the sequentially implemented test for weak separability proposed by Fleissig and Whitney (2003) is low. The theoretically unbiased Swofford and Whitney test (1994) is found to perform better than all sequentially implemented test procedures but is found to suffer from an empirical bias, most likely because of the complexity in executing the test procedure. As a further source of information, we also perform sensitivity analyses on the nonparametric revealed preference tests. It is found that the Fleissig and Whitney test seems to be sensitive to measurement errors in the data
Testing for Rationality, Separability and Efficiency
No full textThis thesis aims to propose, evaluate and apply test procedures for rationality, weak separability and efficiency. In particular, it focuses on nonparametric revealed preference procedures. This approach has the advantage of not having to stipulate any functional form for the utility function, unlike the parametric approach which relies on finding a suitable functional form for the utility function. Many nonparametric approaches to testing rationality and weak separability are based on what is referred to in the literature as Afriat’s theorem. The significance of this theorem is that if the observed data satisfy some testable conditions, then the data may be rationalized by a well-behaved utility function that possesses such properties as being non-satiated, continuous, monotonic and concave. Chapter 2 provides a generalization of Afriat's theorem. It is shown that the concavity condition in the theorem may be relaxed to the weaker assumption of semistrict quasi-concavity. In particular, revealed preference conditions are used to check whether a finite data set can be generated by a non-satiated, continuous, monotone and semistrict quasi-concave utility function. In addition, it is shown that a data set can be checked for consistency with economic theory by solving a simple linear programming problem. Chapter 3 investigates the properties of nonparametric revealed preference tests for weak separability by means of Monte Carlo experiments. A block of goods is said to be weakly separable from all other goods when the marginal rate of substitution between any pair of goods in the separable block does not depend on the quantities consumed of any good that is not in the block. A main finding of this thesis is that the bias of the sequential test proposed by Fleissig and Whitney (2003) is low, but that the performance of the test deteriorates substantially when measurement errors are added to the data. The theoretically unbiased test by Swofford and Whitney (1994) is found to suffer from an empirical bias, most probably because the test is heavily dependent on efficient nonlinear optimization routines. Chapter 4, using a data set that comprises yearly observations from 1963-2002 examines separability structures and the demand for food in the Swedish food market. A data-orientated search method based on the multistep test procedure proposed by Jones, Elger, Edgerton and Dutkowsky (2005) is applied to find an appropriate structuring of goods in the demand analysis. Most agricultural studies assume that animalia products, beverage products and vegetabilia products constitute separable groupings. It is shown that this is a misleading assumption when analysing Swedish food data. Chapter 5, co-authored with Kerstin Enflo, addresses the issue of Western European regional productivity growth and convergence by means of data envelopment analysis (DEA), decomposing labor productivity into efficiency change, technical change and capital accumulation. A main finding is that the relative ranking of efficiency scores obtained using DEA is stable with regard to bias-corrections. The decomposition shows that, on average, capital accumulation and technological change have played roughly equally large roles, whereas efficiency changes have contributed negatively
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
Power against random expenditure allocation for revealed preference tests
No full textThis paper proposes new power indices for revealed preference tests. The indices are based on a model of irrational consumption behavior where the consumer randomly allocates a certain fraction of expenditure. The methods allow a researcher to trace out the entire power curve against random expenditure allocation. The power indices are illustrated on altruistic choices in experimental data
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