Open semantic hyperwikis

Wikis are lightweight, community-editable, web-based hypertext systems, which can be described as a website that anybody can edit. From this collaborative base has grown significant efforts at large-scale knowledge management such as Wikipedia. Recently, ‘semantic’ wiki systems have been developed with typed links, such that the structure of nodes and links is analogous to an RDF graph of resources and arcs: a machineprocessable representation of the relations between articles which can form part of the web of linked data. Despite this, the hypermedia side of wiki systems has so far largely been constrained to the web model of simple embedded, unidirectional links. This research considers the hypertext origins of wiki systems, asks, and answers how the technologies developed during decades of hypertext research may be applied to better manage their document, and thus knowledge, structure. We present experimental evidence supporting the hypothesis that additional hypermedia features would be useful to wiki editors on both macro- and micro-scales. Quantitative analysis of editing logs from a large-scale wiki shows that hyperstructure changes form a substantial proportion of editing effort. Conversely, qualitative user studies show that individual user editing can be better supported by classical but since overlooked hypertext features such as first-class links and transclusion. We then specify an extensive model for a ‘open semantic hyperwiki’ system which draws from these fields, based around first-class links with support for transclusion and advanced functional link types, with defined semantics for the role of versioning and parametric nodes in the linked data world, while mindful to preserve the core simplicity that allows non-expert users to contribute. This is followed by a practical approach to its implementation in terms of an existing experimental modular wiki foundation, and the actual prototype implementation, which has been made available as open source software. Finally, we work through applying the system to a set of real-world use cases which are currently employing classic, non-semantic wiki software, and evaluate the implementation in comparison to a conventional semantic wiki in a user study.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Hyperstructure Maintenance Costs in Large-scale Wikis

Wiki systems have developed over the past years as lightweight, community-editable, web-based hypertext systems. With the emergence of Semantic Wikis, these collections of interlinked documents have also gained a dual role as ad-hoc RDF graphs. However, their roots lie at the limited hypertext capabilities of the World Wide Web: embedded links, without support for composite objects or transclusion. In this paper, we present experimental evidence that hyperstructure changes, as opposed to content changes, form a substantial proportion of editing effort on a large-scale wiki. The experiment is set in the wider context of a study of how the technologies developed during decades of hypertext research may be applied to improve management of wiki document structure and, with semantic wikis, knowledge structure

A Model for Open Semantic Hyperwikis

Wiki systems have developed over the past years as lightweight, community-editable, web-based hypertext systems. With the emergence of semantic wikis such as Semantic MediaWiki, these collections of interlinked documents have also gained a dual role as ad-hoc RDF graphs. However, their roots lie in the limited hypertext capabilities of the World Wide Web: embedded links, without support for features like composite objects or transclusion. Collaborative editing on wikis has been hampered by redundancy; much of the effort spent on Wikipedia is used keeping content synchronised and organised. We have developed a model for a system, which we have prototyped and are evaluating, which reintroduces ideas from the field of hypertext to help alleviate this burden. In this paper, we present a model for what we term an 'open semantic hyperwiki' system, drawing from both past hypermedia models, and the informal model of modern semantic wiki systems. An 'open semantic hyperwiki' is a reformulation of the popular semantic wiki technology in terms of the long-standing field of hypermedia, which then highlights and resolves the omissions of hypermedia technology made by the World Wide Web and the applications built around its ideas. In particular, our model supports first-class linking, where links are managed separately from nodes. This is then enhanced by the system's ability to embed links into other nodes and separate them out again, allowing for a user editing experience similar to HTML-style embedded links, while still gaining the advantages of separate links. We add to this transclusion, which allows for content sharing by including the content of one node into another, and edit-time transclusion, which allows users to edit pages containing shared content without the need to follow a sequence of indirections to find the actual text they wish to modify. Our model supports more advanced linking mechanisms, such as generic links, which allow words in the wiki to be used as link endpoints. The development of this model has been driven by our prior experimental work on the limitations of existing wikis and user interaction. We have produced a prototype implementation which provides first-class links, transclusion, and generic links

Open Semantic Hyperwikis

Wikis are lightweight, community-editable, web-based hypertext systems, which can be described as a website that anybody can edit. From this collaborative base has grown significant efforts at large-scale knowledge management such as Wikipedia. Recently, ‘semantic’ wiki systems have been developed with typed links, such that the structure of nodes and links is analogous to an RDF graph of resources and arcs: a machineprocessable representation of the relations between articles which can form part of the web of linked data. Despite this, the hypermedia side of wiki systems has so far largely been constrained to the web model of simple embedded, unidirectional links. This research considers the hypertext origins of wiki systems, asks, and answers how the technologies developed during decades of hypertext research may be applied to better manage their document, and thus knowledge, structure. We present experimental evidence supporting the hypothesis that additional hypermedia features would be useful to wiki editors on both macro- and micro-scales. Quantitative analysis of editing logs from a large-scale wiki shows that hyperstructure changes form a substantial proportion of editing effort. Conversely, qualitative user studies show that individual user editing can be better supported by classical but since overlooked hypertext features such as first-class links and transclusion. We then specify an extensive model for a ‘open semantic hyperwiki’ system which draws from these fields, based around first-class links with support for transclusion and advanced functional link types, with defined semantics for the role of versioning and parametric nodes in the linked data world, while mindful to preserve the core simplicity that allows non-expert users to contribute. This is followed by a practical approach to its implementation in terms of an existing experimental modular wiki foundation, and the actual prototype implementation, which has been made available as open source software. Finally, we work through applying the system to a set of real-world use cases which are currently employing classic, non-semantic wiki software, and evaluate the implementation in comparison to a conventional semantic wiki in a user study

Semantics on Demand: Can a Semantic Wiki Replace a Knowledge Base?

In the same way that Wikis have become the mechanism that has enabled groups of users to collaborate on the production of hypertexts on the web, Semantic Wikis promise a future of collaboration on the production of semantically linked and ontologically structured hypertexts. In this paper we describe our efforts to convert an existing ontologically structured web site called FREMA into a Semantic Wiki specifically to enable community contribution. We compare a number of existing Semantic Wikis, and explore how the notion of semantics-on-demand affects a system’s ability to control the creation of useful ontologies and annotations. The FREMA case study introduces a number of the problems we encountered and solved, and sets the template for others considering implementing web-based knowledge bases using Semantic Wikis. Our conclusions will contribute to the agenda for those implementing the next generation of Semantic Wikis

There and here: patterns of content transclusion in Wikipedia

As large, collaboratively authored hypertexts such as Wikipedia grow so does the requirement both for organisational principles and methods to provide sustainable consistency and to ease the task of contributing editors. Large numbers of (potential) editors are not necessarily a sufficient bulwark against loss of coherence amongst a corpus of many discrete articles. The longitudinal task of curation may benefit from deliberate curatorial roles and techniques.A potentially beneficial technique for the development and maintenance of hypertext content at scale is hypertext transclusion, by offering controllable re-use of a canonical source. In considering issues of longitudinal support of web collaborative hypertexts, we investigated the current degree and manner of adoption of transclusion facilities by editors of Wikipedia articles. We sampled 20 million articles from ten discrete language wikis within Wikipedia to analyse behaviour both within and across the individual Wikipedia communities.We show that Wikipedia makes limited, inconsistent of use of transclusion (as at February 2016). Use is localised to subject areas, which differ between sampled languages. A limited number of patterns were observed including: Lists from transclusion, Lists of Lists, Episodic Media Listings, Tangles, Articles as Macros, and Self-Transclusion. We find little indication of deliberate structural maintenance of the hypertext

A Bayesian reanalysis of the Standard versus Accelerated Initiation of Renal-Replacement Therapy in Acute Kidney Injury (STARRT-AKI) trial

Background Timing of initiation of kidney-replacement therapy (KRT) in critically ill patients remains controversial. The Standard versus Accelerated Initiation of Renal-Replacement Therapy in Acute Kidney Injury (STARRT-AKI) trial compared two strategies of KRT initiation (accelerated versus standard) in critically ill patients with acute kidney injury and found neutral results for 90-day all-cause mortality. Probabilistic exploration of the trial endpoints may enable greater understanding of the trial findings. We aimed to perform a reanalysis using a Bayesian framework. Methods We performed a secondary analysis of all 2927 patients randomized in multi-national STARRT-AKI trial, performed at 168 centers in 15 countries. The primary endpoint, 90-day all-cause mortality, was evaluated using hierarchical Bayesian logistic regression. A spectrum of priors includes optimistic, neutral, and pessimistic priors, along with priors informed from earlier clinical trials. Secondary endpoints (KRT-free days and hospital-free days) were assessed using zero–one inflated beta regression. Results The posterior probability of benefit comparing an accelerated versus a standard KRT initiation strategy for the primary endpoint suggested no important difference, regardless of the prior used (absolute difference of 0.13% [95% credible interval [CrI] − 3.30%; 3.40%], − 0.39% [95% CrI − 3.46%; 3.00%], and 0.64% [95% CrI − 2.53%; 3.88%] for neutral, optimistic, and pessimistic priors, respectively). There was a very low probability that the effect size was equal or larger than a consensus-defined minimal clinically important difference. Patients allocated to the accelerated strategy had a lower number of KRT-free days (median absolute difference of − 3.55 days [95% CrI − 6.38; − 0.48]), with a probability that the accelerated strategy was associated with more KRT-free days of 0.008. Hospital-free days were similar between strategies, with the accelerated strategy having a median absolute difference of 0.48 more hospital-free days (95% CrI − 1.87; 2.72) compared with the standard strategy and the probability that the accelerated strategy had more hospital-free days was 0.66. Conclusions In a Bayesian reanalysis of the STARRT-AKI trial, we found very low probability that an accelerated strategy has clinically important benefits compared with the standard strategy. Patients receiving the accelerated strategy probably have fewer days alive and KRT-free. These findings do not support the adoption of an accelerated strategy of KRT initiation

Regional Practice Variation and Outcomes in the Standard Versus Accelerated Initiation of Renal Replacement Therapy in Acute Kidney Injury (STARRT-AKI) Trial: A Post Hoc Secondary Analysis.

ObjectivesAmong patients with severe acute kidney injury (AKI) admitted to the ICU in high-income countries, regional practice variations for fluid balance (FB) management, timing, and choice of renal replacement therapy (RRT) modality may be significant.DesignSecondary post hoc analysis of the STandard vs. Accelerated initiation of Renal Replacement Therapy in Acute Kidney Injury (STARRT-AKI) trial (ClinicalTrials.gov number NCT02568722).SettingOne hundred-fifty-three ICUs in 13 countries.PatientsAltogether 2693 critically ill patients with AKI, of whom 994 were North American, 1143 European, and 556 from Australia and New Zealand (ANZ).InterventionsNone.Measurements and main resultsTotal mean FB to a maximum of 14 days was +7199 mL in North America, +5641 mL in Europe, and +2211 mL in ANZ (p p p p p p p p = 0.007).ConclusionsAmong STARRT-AKI trial centers, significant regional practice variation exists regarding FB, timing of initiation of RRT, and initial use of continuous RRT. After adjustment, such practice variation was associated with lower ICU and hospital stay and 90-day mortality among ANZ patients compared with other regions