1,721,083 research outputs found
Uso e (abuso) di prassi di ricerca problematiche in psicologia
Full text linkKeywords: Questionable Research Practices; Research Credibility; Scientific Transparency; Italian Research Psychology.
Le prassi di ricerca problematiche sono prassi metodologiche che aumentano la probabilità di fornire evidenze a supporto di un'ipotesi quando, in realtà, l'evidenza potrebbe essere spuria, introducendo così delle distorsioni nella letteratura scientifica. I bassi tassi di riproducibilità nella letteratura psicologica, riscontrati negli studi di replica, possono essere attribuiti (almeno in parte) all'uso di queste prassi di ricerca. Quali sono le cause della messa in atto delle prassi di ricerca problematiche e la prevalenza del loro utilizzo? John, Loewenstein e Prelec (2012) hanno condotto uno studio andando ad indagare la messa in atto di pratiche di ricerca problematiche con un questionario rivolto a psicologi accademici afferenti ad università statunitensi. I risultati indicano sorprendentemente la presenza di una diffusa messa in atto delle prassi di ricerca problematiche. Uno studio di replica è stato condotto con gli psicologi italiani iscritti all'Associazione Italiana Psicologi. I risultati molto simili ottenuti nei due studi (Stati Uniti e Italia) indicano che le prassi sono ampiamente adottate in ambedue le comunità di ricerca. La somiglianza dei risultati negli Stati Uniti, in Italia e i risultati ottenuti in uno studio simile in Germania, suggerisce che la messa in atto di queste prassi riguarda un fenomeno internazionale, probabilmente dovuto a caratteristiche sistemiche dei processi di ricerca e di pubblicazione
Valutazione dello stato di degrado di materiali lapidei in contesti archeologici: il teatro antico di Taormina
No full textInvestigating the Internal Deterioration of the Auriga Statue of Mozia Island, Sicily, through Ultrasonic and Ground-Penetrating Radar Studies
Full text linkThe Greek marble statue of the Auriga of Mozia Island, in Sicily, is the most important artwork displayed at the Whitaker Foundation Archaeological Museum. It underwent geophysical investigations twice, in 2012 and 2021, to assess the marble’s degradation. The 2012 investigation prepared the statue for transfer to the Paul Getty Museum in New York and repositioning on an anti-seismic pedestal. The 2021 investigation evaluated potential new damage before another transfer. Both investigations utilized 3D ultrasonic tomography (UST) to detect degraded marble areas and ground-penetrating radar (GPR) to identify internal discontinuities, such as fractures or lesions, and locate metal pins that were previously inserted to reassemble the statue and its pedestal. Results from the UST indicate an average marble velocity of approximately 4700 m/s, suggesting good mechanical strength, with some areas showing lower velocities (~3000 m/s) within the material’s variability range. The GPR profiles demonstrated internal signal homogeneity, excluding internal fracture surfaces or lesions, and confirmed the presence of metallic pins. This study highlights the effectiveness of integrating UST and GPR for non-invasive diagnostics of marble sculptures, providing detailed insights into the marble’s condition and identifying hidden defects or damage
Misinterpretation caused by 3D effects on 2D Electrical Resistivity Tomography: tests on simple models
No full textThe aim of this work is to evaluate the effects of 2D inversion of electrical resistivity data when in presence on 3D structures by testing synthetic and experimental models. Several numerical simulations have been calculated for different resistivity models and 2D datasets were extracted to study and quantify the effects of 2D inversion on 3D structures. Results have been compared with field texts carried out in quarrying sites. The main tests here presented simulates prism-shaped cavities with a square vertical section of l x l size and a variable lateral extension d, from l to infinity (this latter being a 2D tunnel model). Inversion of predicted data show that 2D tomography does not always give satisfactory results on cavities that have a more or less limited extension perpendicular to the profile. In all cases the resistivity anomaly obtained by the 2D inversion of a 3D cavity underestimates the true value much more than the inversion of the corresponding 2D model and obviously underestimation increases with three-dimensional characteristics. The effects of three-dimensionality can lead to the identification of false cavities along the vertical or can lead to strong errors in the estimation of depth and size, thus causing misleading statements
Trading activity and price impact in parallel markets: SETS vs. off-book market at the London Stock Exchange
No full textWe study empirically the trading activity in the electronic on-book segment and in the dealership off-book segment of the London Stock Exchange, investigating separately the trading of active market members and of other market participants who are non-members. We find that (i) the volume distribution of off-book transactions has a significantly fatter tail than that of on-book transactions, (ii) groups of members and non-members can be classified in categories according to their trading profile, (iii) there is a strong anticorrelation between the daily inventory variation of a market member due to on-book market transactions and an inventory variation due to off-book market transactions with non-members, and (iv) the autocorrelation of the sign of the orders of non-members in the off-book market is slowly decaying. We also analyse the on-book price impact function over time, both for positive and negative lags, of the electronic trades and of the off-book trades. The unconditional impact curves are very different for the electronic trades and the off-book trades. Moreover, there is a small dependence of the impact on the volume for the on-book electronic trades, while the shape and magnitude of the impact function of off-book transactions strongly depend on volume
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
Vacuum induced spin-1/2 Berry's phase.
No full textWe calculate the Berry phase of a spin-1/2 particle in a magnetic field considering the quantum nature of the field. The phase reduces to the standard Berry phase in the semiclassical limit and the eigenstate of the particle acquires a phase in the vacuum. We also show how to generate a vacuum induced Berry phase considering two quantized modes of the field which has an interesting physical interpretation
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