1,720,995 research outputs found
Roots and (Re)sources of Value (In)definiteness Versus Contextuality
No full textIn Itamar Pitowskys Lesart des Gleason- und des Kochen-Specker-Theorems, insbesondere seines Prinzips der logischen Unbestimmtheit, liegt die Betonung auf der Wertunbestimmtheit von Beobachtungsgrößen, die nicht im Präparationskontext stehen. Dies steht in krassem Gegensatz zu dem vorherrschenden Begriff der Kontextabhängigkeit, der von vielen Forschern auf informelle, heuristische, aber omni-realistische und potenziell irreführende Weise verwendet wird. In diesem Aufsatz werden beide Konzepte diskutiert und es wird für eine Wertunbestimmtheit in allen außer einem Kontinuum von Kontexten argumentiert, die sich in dem Vektor, der einen einzigen reinen (präparierten) Zustand darstellt, ineinander verflechten. Noch restriktiver und inspiriert durch den Operationalismus, aber nicht gerechtfertigt durch Pitowskys Logisches Unbestimmtheitsprinzip oder ähnliches, könnte man mit einem "Quantenzustand" einen einzelnen Quantenkontext -- alias das jeweilige maximal beobachtbare oder, in Bezug auf seine spektrale Zerlegung, die zugehörige orthonormale Basis -- aus dem Kontinuum der ineinander verschränkte Kontexte identifizieren, wie pro das zugehörige maximal beobachtbare, tatsächlich oder implizit vorbereitete.In Itamar Pitowsky's reading of the Gleason and the Kochen-Specker theorems, in particular, his Logical Indeterminacy Principle, the emphasis is on the value indefiniteness of observables which are not within the preparation context. This is in stark contrast to the prevalent term contextuality used by many researchers in informal, heuristic yet omni-realistic and potentially misleading ways. This paper discusses both concepts and argues in favor of value indefiniteness in all but a continuum of contexts intertwining in the vector representing a single pure (prepared) state. Even more restrictively, and inspired by operationalism but not justified by Pitowsky's Logical Indeterminacy Principle or similar, one could identify with a ``quantum state" a single quantum context -- aka the respective maximal observable, or, in terms of its spectral decomposition, the associated orthonormal basis -- from the continuum of intertwining context, as per the associated maximal observable actually or implicitly prepared
Agents in Healey’s Pragmatist Quantum Theory: A Comparison with Pitowsky’s Approach to Quantum Mechanics
No full textIn a series of related papers and in a book (Healey R. The quantum
revolution in philosophy. Oxford University Press, Oxford, 2017b), Richard Healey
has proposed and articulated a new pragmatist approach to quantum theory that I
will refer to as PQT. After briefly reviewing PQT by putting it into a more general
philosophical context, I will discuss Healey’s self-proclaimed quantum realism by
stressing that his agent-centered approach to quantum mechanics makes his position
rather close to a sophisticated form of instrumentalist, despite his claims to the
contrary. My discussion of the possible sources of incompatibility between PQT
and the view that agents can be regarded as physical systems (agent physicalism)
will allow me to compare Healey’s view of quantum theory with Pitowsky’s. In
particular, by focusing on the measurement problem, I will discuss the role of
observers and the notion of information in their respective philosophical approach
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
- …
