131,263 research outputs found
MLDS: Maximum Likelihood Difference Scaling in R
No full textThe MLDS package in the R programming language can be used to estimate perceptual scales based on the results of psychophysical experiments using the method of difference scaling. In a difference scaling experiment, observers compare two supra-threshold differences (a,b) and (c,d) on each trial. The approach is based on a stochastic model of how the observer decides which perceptual difference (or interval) (a,b) or (c,d) is greater, and the parameters of the model are estimated using a maximum likelihood criterion. We also propose a method to test the model by evaluating the self-consistency of the estimated scale. The package includes an example in which an observer judges the differences in correlation between scatterplots. The example may be readily adapted to estimate perceptual scales for arbitrary physical continua.
Repräsentationen taktischen Verhaltens im Fußball
No full textLex H, Pollmann D, Knoblauch A, Schack T. Repräsentationen taktischen Verhaltens im Fußball. In: 48. Kongress der Deutschen Gesellschaft für Psychologie (DGPs). Bielefeld: Pabst Science Publishers; 2012: 125
Monitoring & Information Center for Human Rights Violations during the Pandemic of COVID-19
No full textHuman Dignity Observatory / #PandemicWithoutHarm
The visibility of human rights violations contributes to the strengthening of democracy and the defense of the rule of law. The political and social impact as a tool we are developing for human rights defenders and researchers.
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Observatorio de Dignidad Humana / #PandemiaSinAbusosAbstract
La visibilidad de las violaciones de los derechos humanos contribuye al fortalecimiento de la democracia y a la defensa del Estado de Derecho. El impacto político y social como herramienta que estamos desarrollando para defensores de los derechos humanos e investigadores.Cite article:
"Díaz Velásquez, M. I., Molina Aguilar, J., Baños, S. A., & Espin García, O. H. (2021). Human Dignity Observatory. In D. Kreher (Ed.), Knowmad Institut (Vol. 2, Issue 1). Knowmad Institut gemeinnützige UG (haftungsbeschränkt); Knowmad Institut gemeinnützige UG (haftungsbeschränkt). https://knowmadinstitut.org/2020/04/quarantine-hhrr/ | Civil Society Partners: FESPAD (El Salvador), REDUC (Brazil) , LGBTI Mexico (Mexico) | Advisors: Navas, N., & Knoblauch, M. Volunteers: Torres, M., & Romero, O | CC BY-NC 4.0 // 2020 | Map user content has been published under licence Licence ouverte/Open Licence Map background credits OSM Dark (jawgmaps) Tiles courtesy of jawgmaps - Map data © OpenStreetMap contributors, under ODbL." https://knowmadinstitut.org/2020/04/quarantine-hhrr/ Civil Society Partners: FESPAD (El Salvador), REDUC (Brazil) , LGBTI Mexico (Mexico) Advisors: Navas, N., & Knoblauch, M. | Volunteers: Torres, M., & Romero, O CC BY-NC 4.0 // 2021 | Map user content has been published under licence Licence ouverte/Open Licence | Map background credits OSM Dark (jawgmaps) Tiles courtesy of jawgmaps - Map data © OpenStreetMa
Schichtung ohne Interaktionsbezug: Eine moderne Sozialstruktur und ihre semantischen Korrelate
No full textKieserling A. Schichtung ohne Interaktionsbezug: Eine moderne Sozialstruktur und ihre semantischen Korrelate. In: Tänzler D, Knoblauch H, Soeffner H-G, eds. Neue Perspektiven der Wissenssoziologie. Erfahrung, Wissen, Imagination. Vol 8. Konstanz: UVK.-Verl.-Ges.; 2006: 346
Expertiseabhängige Unterschiede kognitiver Repräsentationen mannschaftstaktischen Verhaltens im Fußball
No full textLex H, Pollmann D, Knoblauch D, Schack T. Expertiseabhängige Unterschiede kognitiver Repräsentationen mannschaftstaktischen Verhaltens im Fußball. In: Baumgart C, Hoppe MW, Freiwald J, eds. Trainingswissenschaftliche, geschlechtsspezifische und medizinische Aspekte des Hochleistungsfußballs - Beiträge und Analysen zum Fußballsport XVIII. dvs. Vol 222. Hannover: Feldhaus Verlag; 2012: 183-188
MeSH term explosion and author rank improve expert recommendations
No full textInformation overload is an often-cited phenomenon that reduces the productivity, efficiency and efficacy of scientists. One challenge for scientists is to find appropriate collaborators in their research. The literature describes various solutions to the problem of expertise location, but most current approaches do not appear to be very suitable for expert recommendations in biomedical research. In this study, we present the development and initial evaluation of a vector space model-based algorithm to calculate researcher similarity using four inputs: 1) MeSH terms of publications; 2) MeSH terms and author rank; 3) exploded MeSH terms; and 4) exploded MeSH terms and author rank. We developed and evaluated the algorithm using a data set of 17,525 authors and their 22,542 papers. On average, our algorithms correctly predicted 2.5 of the top 5/10 coauthors of individual scientists. Exploded MeSH and author rank outperformed all other algorithms in accuracy, followed closely by MeSH and author rank. Our results show that the accuracy of MeSH term-based matching can be enhanced with other metadata such as author rank
Die Dokumentation qualitativer Interviews im Rahmen von Organisationsstudien
No full textGebel T, Liebig S. Die Dokumentation qualitativer Interviews im Rahmen von Organisationsstudien. In: Huschka D, Knoblauch H, Oellers C, Solga H, eds. Forschungsinfrastrukturen. Berlin: Scivero; 2013: 73-90
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Circadian and homeostatic modulation of sleep spindles in the human electroencephalogram
No full textSleep spindles are transient EEG oscillations of about 12-16 Hz. Together with slow waves, they hallmark the human non-REM sleep EEG. Sleep spindles originate in the thalamus and are suggested to have a sleep protective function by reducing sensory transmission to the cortex. Other evidence points to an involvement of sleep spindles in brain plasticity processes during sleep. Previous studies have shown that sleep spindles are both under homeostatic (sleep-wake dependent) and circadian (time of day-dependent) control. Furthermore, frequency-specific topographical distribution of power density within the spindle frequency range has been reported. The aim of this thesis was to assess homeostatic and circadian influences on spectral spindle frequency activity (SFA) and spindle parameters in different brain regions. Healthy young volunteers participated in both a 40-h sleep deprivation (SD) and a 40-h multiple nap paradigm. The recovery nights after the SD and the nap protocol served to assess the effect of enhanced and reduced homeostatic sleep pressure, respectively. The multiple nap paradigm revealed the modulation of sleep spindles across the circadian cycle. Two different methodological approaches were used to analyze the EEGs: classical spectral analysis (Fast Fourier Transform, FFT) and a new method for instantaneous spectral analysis (Fast Time Frequency Transform, FTFT), developed as a part of this thesis project in collaboration with Wim Martens from TEMEC, The Netherlands. Slow wave activity (SWA, spectral power density in the 0.75-4.5 Hz range) and spindle frequency activity (SFA, spectral power density in the spindle frequency range) in the high frequency range (13.75-16.5 Hz) were oppositely affected by the differential levels of sleep pressure (Chapter 2). These effects strongly depended on brain location. After SD, the SWA increase compared to the baseline night was most pronounced in the beginning of the night and in the fronto-central region. Power density in the high spindle frequency range was reduced in the centro-parietal brain region. After the nap protocol, when sleep pressure was reduced, power density in the SWA range was decreased at the beginning of the night. SFA was generally increased after the nap protocol. The data indicate that the balance between SWA and high-frequency spindle activity may represent a sensitive marker for the level of
homeostatic sleep pressure.
The new method of FTFT revealed that spindle density was reduced after SD
(Chapter 3). This reduction was particularly apparent in the frontal derivation, and
most pronounced in the first half of the night. The reduction of spindle density with its
temporal and local specificity confirms the inverse homeostatic regulation of slow
waves and sleep spindles. Sleep spindles had a lower frequency and a higher
amplitude after SD. Within an individual spindle, frequency variability was reduced,
which indicates that sleep spindles were more stable and homogenous after SD. The
increase in spindle amplitude and the reduced intra-spindle frequency variability
suggests a higher degree of synchronization in thalamocortical neurons under high
homeostatic sleep pressure.
EEGs during the nap paradigm were analyzed to compare SFA and sleep
spindle characteristics during and outside the circadian phase of melatonin secretion
(the “biological night” and “biological day”, respectively) (Chapter 4). In naps
occurring during the phase of melatonin secretion, lower spindle frequencies were
promoted, indexed as a reduction in mean spindle frequency (i.e. slowing of sleep
spindles) and an increase in spindle amplitude and SFA in the low-frequency range
(up to ~14.25 Hz) paralleled by a reduction in the high-frequency range (~ 14.5-16
Hz). Furthermore, spindle density was increased, and intra-spindle frequency
variability reduced during the night. Thus, the circadian pacemaker is likely to
promote low-frequency, high amplitude and homogenous sleep spindles during the
biological night. The circadian modulation of sleep spindles may be a way by which
the circadian system modulates and times sleep consolidation. This circadian
modulation clearly depended on brain location such that it was maximal in the
parietal and minimal in the frontal derivation.
Taken together, the segregated analysis of different spindle parameters by the
new high-time and high-frequency resolution spindle analysis provides new insights
into sleep spindles and their regulation. Both homeostatic and circadian processes
affected sleep spindles characteristics in a topography-specific manner. These statedependent
local aspects provide further evidence that sleep is a dynamic
phenomenon which reflects use-dependent recovery or reactivation processes
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