WHEN IS CROWDSOURCING ADVANTAGEOUS? THE CASE OF CROWDSOURCED SOFTWARE TESTING

Crowdsourcing describes a novel mode of value creation in which organizations broadcast tasks that have been previously performed in-house to a large magnitude of Internet users that perform these tasks. Although the concept has gained maturity and has proven to be an alternative way of problem-solving, an organizational cost-benefit perspective has largely been neglected by existing research. More specifically, it remains unclear when crowdsourcing is advantageous in comparison to alterna-tive governance structures such as in-house production. Drawing on crowdsourcing literature and transaction action cost theory, we present two case studies from the domain of crowdsourced software testing. We systematically analyze two organizations that applied crowdtesting to test a mobile appli-cation. As both organizations tested the application via crowdtesting and their traditional in-house testing, we are able to relate the effectiveness of crowdtesting and the associated costs to the effective-ness and costs of in-house testing. We find that crowdtesting is comparable in terms of testing quality and costs, but provides large advantages in terms of speed, heterogeneity of testers and user feedback as added value. We contribute to the crowdsourcing literature by providing first empirical evidence about the instances in which crowdsourcing is an advantageous way of problem solving

Integrated quantized electronics: a semiconductor quantized voltage source

The Josephson effect in superconductors links a quantized output voltage Vout = f \cdot(h/2e) to the natural constants of the electron's charge e, Planck's constant h, and to an excitation frequency f with important applications in electrical quantum metrology. Also semiconductors are routinely applied in electrical quantum metrology making use of the quantum Hall effect. However, despite their broad range of further applications e.g. in integrated circuits, quantized voltage generation by a semiconductor device has never been obtained. Here we report a semiconductor quantized voltage source generating quantized voltages Vout = f\cdot(h/e). It is based on an integrated quantized circuit of a single electron pump operated at pumping frequency f and a quantum Hall device monolithically integrated in series. The output voltages of several \muV are expected to be scalable by orders of magnitude using present technology. The device might open a new route towards the closure of the quantum metrological triangle. Furthermore it represents a universal electrical quantum reference allowing to generate quantized values of the three most relevant electrical units of voltage, current, and resistance based on fundamental constants using a single device.Comment: 15 pages, 3 figure

A quantized current source with mesoscopic feedback

We study a mesoscopic circuit of two quantized current sources, realized by non-adiabatic single- electron pumps connected in series with a small micron-sized island in between. We find that quantum transport through the second pump can be locked onto the quantized current of the first one by a feedback due to charging of the mesoscopic island. This is confirmed by a measurement of the charge variation on the island using a nearby charge detector. Finally, the charge feedback signal clearly evidences loading into excited states of the dynamic quantum dot during single-electron pump operation

Algorithmic Management: Its Implications for Information Systems Research

In recent years, the topic of algorithmic management has received increasing attention in information systems (IS) research and beyond. As both emerging platform businesses and established companies rely on artificial intelligence and sophisticated software to automate tasks previously done by managers, important organizational, social, and ethical questions emerge. However, a cross-disciplinary approach to algorithmic management that brings together IS perspectives with other (sub-)disciplines such as macro- and micro-organizational behavior, business ethics, and digital sociology is missing, despite its usefulness for IS research. This article engages in cross-disciplinary agenda setting through an in-depth report of a professional development workshop (PDW) entitled “Algorithmic Management: Toward a Cross-Disciplinary Research Agenda” delivered at the 2021 Academy of Management Annual Meeting. Three leading experts (Mareike Möhlmann, Lindsey Cameron, and Laura Lamers) on the topic provide their insights on the current status of algorithmic management research, how their work contributes to this area, where the field is heading in the future, and what important questions should be answered going forward. These accounts are followed up by insights from the breakout group discussions at the PDW that provided further input. Overall, the experts and workshop participants highlighted that future research should examine both the desirable and undesirable outcomes of algorithmic management and should not shy away from posing ethical and normative questions

Ketamine Alters Functional Gamma and Theta Resting-State Connectivity in Healthy Humans: Implications for Schizophrenia Treatment Targeting the Glutamate System

Disturbed functional connectivity is assumed to cause neurocognitive deficits in patients suffering from schizophrenia. A Glutamate N-methyl-D-aspartate receptor (NMDAR) dysfunction has been suggested as a possible mechanism underlying altered connectivity in schizophrenia, especially in the gamma- and theta-frequency range. The present study aimed to investigate the effects of the NMDAR-antagonist ketamine on resting-state power, functional connectivity, and schizophrenia-like psychopathological changes in healthy volunteers. In a placebo-controlled crossover design, 25 healthy subjects were recorded using resting-state 64-channel-electroencephalography (EEG) (eyes closed). The imaginary coherence-based Multivariate Interaction Measure (MIM) was used to measure gamma and theta connectivity across 80 cortical regions. The network-based statistic was applied to identify involved networks under ketamine. Psychopathology was assessed with the Positive and Negative Syndrome Scale (PANSS) and the 5-Dimensional Altered States of Consciousness Rating Scale (5D-ASC). Ketamine caused an increase in all PANSS (p < 0.001) as well as 5D-ASC scores (p < 0.01). Significant increases in resting-state gamma and theta power were observed under ketamine compared to placebo (p < 0.05). The source-space analysis revealed two distinct networks with an increased mean functional gamma- or theta-band connectivity during the ketamine session. The gamma-network consisted of midline regions, the cuneus, the precuneus, and the bilateral posterior cingulate cortices, while the theta-band network involved the Heschl gyrus, midline regions, the insula, and the middle cingulate cortex. The current source density (CSD) within the gamma-band correlated negatively with the PANSS negative symptom score, and the activity within the gamma-band network correlated negatively with the subjective changed meaning of percepts subscale of the 5D-ASC. These results are in line with resting-state patterns seen in people who have schizophrenia and argue for a crucial role of the glutamate system in mediating dysfunctional gamma- and theta-band-connectivity in schizophrenia. Resting-state networks could serve as biomarkers for the response to glutamatergic drugs or drug development efforts within the glutamate system

Prävalenz von sexuell und durch Blut übertragenen Infektionen und Tuberkulose bei Menschen in Wohnungs­losigkeit in Berlin – Erste Ergebnisse der Pilotstudie POINT

Das RKI hat in Kooperation mit Fixpunkt e. V. und BeSog Berliner Sozialprojekte gGmbH die Querschnittsstudie POINT initiiert, um valide Aussagen zur Prävalenz von sexuell und durch Blut übertragbaren Infektionen und Tuberkulose bei wohnungslosen Personen treffen zu können. Mit den gewonnenen Daten sollen Präventions- und Versorgungsangebote ausgestaltet sowie internationale Strategien zur Eliminierung der untersuchten Infektionen unterstützt werdenPeer Reviewe

Prävalenz von sexuell und durch Blut übertragenen Infektionen und Tuberkulose bei Menschen in Wohnungs­losigkeit in Berlin – Erste Ergebnisse der Pilotstudie POINT

Das RKI hat in Kooperation mit Fixpunkt e. V. und BeSog Berliner Sozialprojekte gGmbH die Querschnittsstudie POINT initiiert, um valide Aussagen zur Prävalenz von sexuell und durch Blut übertragbaren Infektionen und Tuberkulose bei wohnungslosen Personen treffen zu können. Mit den gewonnenen Daten sollen Präventions- und Versorgungsangebote ausgestaltet sowie internationale Strategien zur Eliminierung der untersuchten Infektionen unterstützt werdenPeer Reviewe

Auditory verbal hallucinations and the interhemispheric auditory pathway in chronic schizophrenia

Objectives—The interhemispheric auditory pathway has been shown to play a crucial role in the processing of acoustic stimuli, and alterations of structural and functional connectivity between bilateral auditory areas are likely relevant to the pathogenesis of auditory verbal hallucinations (AVHs). The aim of this study was to examine this pathway in patients with chronic schizophrenia regarding their lifetime history of AVHs. Methods—DTI scans were acquired from 33 healthy controls (HC), 24 schizophrenia patients with a history of AVHs (LT-AVH) and 9 schizophrenia patients without any lifetime hallucinations (N-LT-AVH). The interhemispheric auditory fibre bundles were extracted using streamline tractography. Subsequently, diffusivity indices, namely Fractional Anisotropy (FA), Trace, Mode, Axial and Radial Diffusivity, were calculated.Results—FA was decreased over the entire pathway in LT-AVH compared with N-LT-AVH. Moreover, LT-AVH displayed decreased FA and Mode as well as increased Radial Diffusivity in the midsagittal section of the fibre tract. Conclusions—These findings indicate complex microstructural changes in the interhemispheric auditory pathway of schizophrenia patients with a history of AVHs. Alterations appear to be absent in patients who have never hallucinated