ORCID Profile
0000-0002-9656-5932
Current Organisations
Curtin University
,
University of KwaZulu-Natal
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Publisher: eLife Sciences Publications, Ltd
Date: 14-09-2020
DOI: 10.7554/ELIFE.57067
Abstract: The proportion of research outputs published in open access journals or made available on other freely-accessible platforms has increased over the past two decades, driven largely by funder mandates, institutional policies, grass-roots advocacy, and changing attitudes in the research community. However, the relative effectiveness of these different interventions has remained largely unexplored. Here we present a robust, transparent and updateable method for analysing how these interventions affect the open access performance of in idual institutes. We studied 1,207 institutions from across the world, and found that, in 2017, the top-performing universities published around 80–90% of their research open access. The analysis also showed that publisher-mediated (gold) open access was popular in Latin American and African universities, whereas the growth of open access in Europe and North America has mostly been driven by repositories.
Publisher: Zenodo
Date: 2022
Publisher: Zenodo
Date: 2020
Publisher: Zenodo
Date: 2020
Publisher: MDPI AG
Date: 24-08-2022
DOI: 10.3390/MIN12091065
Abstract: Governance of abandoned mines has become a pressing issue for China. The utilization of abandoned mines is a technology that can solve the problem of governance and recreate the value of mines, which is in line with the current strategic goals of ecological protection and double carbon in China. In this paper, the various utilization models and the advances in rock mechanics of abandoned mines across the globe are summarized and reviewed. The utilization models of abandoned mines can be categorized into four aspects: Energy storage, Waste treatment, Ecological restoration, and carbon dioxide (CO2) sequestration. There are a number of applications and uses of abandoned mines, such as pumped storage, compressed air storage, salt cavern gas/oil storage construction, carbon dioxide storage and utilization, radioactive waste disposal and treatment, and tourism development. Various progress practices of abandoned mines are discussed in detail with emphasis on the national conditions of China. The basic rock mechanics problems and advances involved in the construction of the facilities related to the utilization of abandoned mines are discussed and evaluated. The establishment of relevant research and experimental platforms will contribute to the sustainable development of China’s mining industry and the improvement of clean technologies.
Publisher: Zenodo
Date: 2023
Publisher: Springer International Publishing
Date: 2021
DOI: 10.1007/978-3-030-71305-8_36
Abstract: The Curtin Open Knowledge Initiative (COKI) is an innovative research project that collects and analyses publicly available research output data to assist and encourage researchers, academics, administrators and executives to understand the actual and potential reach of openness in research, and to assess their progress on the path towards open knowledge institutions. By taking a broad global approach and using multiple data sources, the project erges from existing approaches, methods and bibliometric measures in the scholarly research environment. It combines analysis of research output, citations, publication sources and publishers, funders, social media events, open and not open access to provide overviews of research output and performance at institutional, funder, consortial and country levels. The project collects and analyses personnel ersity data such as gender, focusing on widening the reach of data analysis to emphasise the importance and value of ersity in research and knowledge production. Interactive visual tools present research output and performance to encourage understanding and dialogue among researchers and management. The path towards becoming open knowledge institutions involves a process of cultural change, moving beyond dominant publishing and evaluation practices. This paper discusses how through ergence, ersity and dialogue the COKI project can contribute to this change, with ex les of applications in understanding and embracing openness.
Publisher: Ligue des Bibliotheques Europeennes de Recherche
Date: 03-11-2022
DOI: 10.53377/LQ.11544
Abstract: In the current era of worldwide competition in higher education, universities are caught up in market processes that encourage compliance with the measurement systems applied by world university rankings. Despite questions about the rankings’ methodologies and data sources, universities continue to adopt assessment and evaluation practices that require academic researchers to publish in sources indexed by the major commercial bibliographic databases used by world rankings. Building on a critique of the limited bibliometric measures and underlying assumptions of rankings, the Curtin Open Knowledge Initiative interdisciplinary research project aggregates and analyses scholarly research data including open access output from multiple open sources for more than 20,000 institutions worldwide. To understand who is creating knowledge and how ersity is enacted through the transmission of knowledge we analyse workforce demographic data. In this article, we discuss the project’s rationale, methodologies and ex les of data analysis that can enable universities to make independent assessments, ask questions about rankings, and contribute to open knowledge-making and sharing. Expanding on our presentation to the LIBER Online 2021 Conference, we discuss collaboration with academic libraries and other scholarly communication stakeholders to develop and extend the open knowledge project.
Publisher: Zenodo
Date: 2022
Publisher: Zenodo
Date: 2019
Publisher: Zenodo
Date: 2019
Publisher: Zenodo
Date: 2019
Publisher: Ligue des Bibliotheques Europeennes de Recherche
Date: 31-10-2019
DOI: 10.18352/LQ.10298
Publisher: Zenodo
Date: 2019
Publisher: Clute Institute
Date: 27-02-2014
Abstract: South Africa is a cornucopia of mineral riches and the performance of its mining industry has significant impacts on the economy. Hence, an accurate distributional assumption of the underlying mining index returns is imperative for the forecasting and understanding of the financial market. In this paper, we propose three subclasses of the generalized hyperbolic distributions as appropriate models for the Johannesburg Stock Exchange (JSE) Mining Index returns. These models are shown to outperform the traditional assumption of normality and accommodate for a number of stylized features, such as excess kurtosis and volatility clustering, embedded within the financial data. The models are compared using the Akaike Information Criterion (AIC), the Bayesian Information Criterion (BIC) and log-likelihoods. In addition, Value-at-Risk (VaR) estimation and backtesting were also performed to test the extreme tails. The various criteria utilized suggest the generalized hyperbolic (GH) skew Students t-distribution as the most robust model for the South African Mining Index returns.
Publisher: Zenodo
Date: 2015
Publisher: Zenodo
Date: 2017
Publisher: MIT Press - Journals
Date: 08-2020
DOI: 10.1162/QSS_A_00052
Abstract: Pressured by globalization and demand for public organizations to be accountable, efficient, and transparent, university rankings have become an important tool for assessing the quality of higher education institutions. It is therefore important to assess exactly what these rankings measure. Here, the three major global university rankings—the Academic Ranking of World Universities, the Times Higher Education ranking and the Quacquarelli Symonds World University Rankings—are studied. After a description of the ranking methodologies, it is shown that university rankings are stable over time but that there is variation between the three rankings. Furthermore, using principal component analysis and exploratory factor analysis, we demonstrate that the variables used to construct the rankings primarily measure two underlying factors: a university’s reputation and its research performance. By correlating these factors and plotting regional aggregates of universities on the two factors, differences between the rankings are made visible. Last, we elaborate how the results from these analysis can be viewed in light of often-voiced critiques of the ranking process. This indicates that the variables used by the rankings might not capture the concepts they claim to measure. The study provides evidence of the ambiguous nature of university rankings quantification of university performance.
Publisher: OpenEdition Press
Date: 29-05-2019
Publisher: No publisher found
Date: 2020
Publisher: Zenodo
Date: 2022
Publisher: Springer Science and Business Media LLC
Date: 14-08-2017
Publisher: Clute Institute
Date: 30-06-2014
Abstract: It has been well documented that the empirical distribution of daily logarithmic returns from financial market variables is characterized by excess kurtosis and skewness. In order to capture such properties in financial data, heavy-tailed and asymmetric distributions are required to overcome shortfalls of the widely exhausted classical normality assumption. In the context of financial forecasting and risk management, the accuracy in modeling the underlying returns distribution plays a vital role. For ex le, risk management tools such as value-at-risk (VaR) are highly dependent on the underlying distributional assumption, with particular focus being placed at the extreme tails. Hence, identifying a distribution that best captures all aspects of the given financial data may provide vast advantages to both investors and risk managers. In this paper, we investigate major financial indices on the Johannesburg Stock Exchange (JSE) and fit their associated returns to classes of heavy tailed distributions. The relative adequacy and goodness-of-fit of these distributions are then assessed through the robustness of their respective VaR estimates. Our results indicate that the best model selection is not only variant across the indices, but also across different VaR levels and the dissimilar tails of return series.
Publisher: Zenodo
Date: 2016
Publisher: Zenodo
Date: 2020
Publisher: Zenodo
Date: 2016
Publisher: Humanities Commons
Date: 2020
DOI: 10.17613/TYHV-H252
Publisher: Zenodo
Date: 2013
Publisher: Clute Institute
Date: 03-2017
Abstract: The resource sector accounts for a substantial proportion of market capitalization on the US and South African stock exchanges. Hence, severe movements in related stock prices can drastically affect the risk profile of the entire market. Extreme value theory provides a basis for evaluating and forecasting such sporadic occurrences. In this article, we compare performances of classical extreme value models against the recently suggested generalized logistic distribution, for estimating value-at-risk and expected shortfall in resource indices. Our results suggest a significant difference in risk behavior between the two markets and the generalized logistic distribution does not always outperform classical models, as previous work may have suggested.
Publisher: OpenEdition Press
Date: 18-04-2020
Publisher: Zenodo
Date: 2014
Publisher: Walter de Gruyter GmbH
Date: 2020
DOI: 10.5334/CSCI.136
Abstract: This paper explores the concept of ‘open’ knowledge – and the growing importance of digital literacies in supporting a transformation of universities into open knowledge institutions. In order to operate as successful open knowledge institutions, universities must do more than support the transmission of research outcomes from experts located within the university to external communities. They must engage in knowledge-making with communities. This involves questions of equity, ersity and inclusion – who gets to make knowledge as well the role of productive interactions across boundaries (disciplines/university/wider community) in its growth and spread. There is a genuine desire among many universities, research funders, and researchers themselves, to address the challenges of ersity, equity and impact implicit in the open knowledge agenda. However, open knowledge aspirations are being stymied by comparative rankings that are built on data that excludes the work of entire disciplines, continents and languages and are not capable of capturing important aspects of the value universities create. Many of the stakeholders using these rankings to inform decision-making are unaware of the prejudices and blind spots that current measurement tools create and perpetuate. They are also unaware that it is possible to interact critically with the tools used to measure and narrate performance to demand that new questions are asked of the digital traces that universities and research communities create and build better tools for understanding the role of universities in processes of knowledge-making and sharing. As this paper discusses, the Curtin Open Knowledge Initiative, a major research project funded by Curtin University, is a deliberate effort to support the new forms of digital literacy needed to enable this shift.
Publisher: Zenodo
Date: 2019
Publisher: Zenodo
Date: 2019
Publisher: Cold Spring Harbor Laboratory
Date: 21-03-2020
DOI: 10.1101/2020.03.19.998336
Abstract: Open Access to research outputs is becoming rapidly more important to the global research community and society. Changes are driven by funder mandates, institutional policy, grass-roots advocacy and culture change. It has been challenging to provide a robust, transparent and updateable analysis of progress towards open access that can inform these interventions, particularly at the institutional level. Here we propose a minimum reporting standard and present a large-scale analysis of open access progress across 1,207 institutions world-wide that shows substantial progress being made. The analysis detects responses that coincide with policy and funding interventions. Among the striking results are the high performance of Latin American and African universities, particularly for gold open access, whereas overall open access levels in Europe and North America are driven by repository-mediated access. We present a top-100 of global universities with the world’s leading institutions achieving around 80% open access for 2017 publications.
Publisher: Cold Spring Harbor Laboratory
Date: 09-2019
DOI: 10.1101/750075
Abstract: Universities are increasingly evaluated, both internally and externally on the basis of their outputs. Often these are converted to simple, and frequently contested, rankings based on quantitative analysis of those outputs. These rankings can have substantial implications for student and staff recruitment, research income and perceived prestige of a university. Both internal and external analyses usually rely on a single data source to define the set of outputs assigned to a specific university. Although some differences between such databases are documented, few studies have explored them at the institutional scale and examined the implications of these differences for the metrics and rankings that are derived from them. We address this gap by performing detailed bibliographic comparisons between three key databases: Web of Science (WoS), Scopus and, the recently relaunched Microsoft Academic (MSA). We analyse the differences between outputs with DOIs identified from each source for a s le of 155 universities and supplement this with a detailed manual analysis of the differences for fifteen universities. We find significant differences between the sources at the university level. Sources differ in the publication year of specific objects, the completeness of metadata, as well as in their coverage of disciplines, outlets, and publication type. We construct two simple rankings based on citation counts and open access status of the outputs for these universities and show dramatic changes in position based on the choice of bibliographic data sources. Those universities that experience the largest changes are frequently those from non-English speaking countries and those that are outside the top positions in international university rankings. Overall MSA has greater coverage than Scopus or WoS, but has less complete affiliation metadata. We suggest that robust evaluation measures need to consider the effect of choice of data sources and recommend an approach where data from multiple sources is integrated to provide a more robust dataset.
Publisher: Zenodo
Date: 2019
Publisher: PeerJ
Date: 11-05-2021
DOI: 10.7717/PEERJ.11391
Abstract: While the movement for open research has gained momentum in recent years, there remain concerns about the broader commitment to openness in knowledge production and dissemination. Increasingly, universities are under pressure to transform themselves to engage with the wider community and to be more inclusive. Open knowledge institutions (OKIs) provide a framework that encourages universities to act with the principles of openness at their centre not only should universities embrace digital open access (OA), but also lead actions in cultivating ersity, equity, transparency and positive changes in society. This leads to questions of whether we can evaluate the progress of OKIs and what are potential indicators for OKIs. As an exploratory study, this article reports on the collection and analysis of a list of potential OKI indicators. Data for these indicators are gathered for 43 Australian universities. The indicators provide high-dimensional and complex signals about university performances. They show evidence of large disparities in characteristics such as Indigenous employment and gender equity, and a preference for repository-mediated OA across Australian universities. We demonstrate use of the OKI evaluation framework to categorise these indicators into three platforms of ersity, communication and coordination. The analysis provides new insights into the Australian open knowledge landscape and ways of mapping different paths of OKIs.
Publisher: Wiley
Date: 12-05-2014
DOI: 10.1111/SAJE.12051
Publisher: Elsevier BV
Date: 07-2017
Publisher: Infopro Digital Services Limited
Date: 2019
Publisher: Zenodo
Date: 2009
Publisher: MIT Press - Journals
Date: 10-03-2020
DOI: 10.1162/QSS_A_00031
Abstract: Universities are increasingly evaluated on the basis of their outputs. These are often converted to simple and contested rankings with substantial implications for recruitment, income, and perceived prestige. Such evaluation usually relies on a single data source to define the set of outputs for a university. However, few studies have explored differences across data sources and their implications for metrics and rankings at the institutional scale. We address this gap by performing detailed bibliographic comparisons between Web of Science (WoS), Scopus, and Microsoft Academic (MSA) at the institutional level and supplement this with a manual analysis of 15 universities. We further construct two simple rankings based on citation count and open access status. Our results show that there are significant differences across databases. These differences contribute to drastic changes in rank positions of universities, which are most prevalent for non-English-speaking universities and those outside the top positions in international university rankings. Overall, MSA has greater coverage than Scopus and WoS, but with less complete affiliation metadata. We suggest that robust evaluation measures need to consider the effect of choice of data sources and recommend an approach where data from multiple sources is integrated to provide a more robust data set.
Publisher: Zenodo
Date: 2021
Publisher: eLife Sciences Publications, Ltd
Date: 13-08-2020
Publisher: Cold Spring Harbor Laboratory
Date: 21-03-2020
DOI: 10.1101/2020.03.19.998542
Abstract: In the article “Evaluating institutional open access performance: Methodology, challenges and assessment” we develop the first comprehensive and reproducible workflow that integrates multiple bibliographic data sources for evaluating institutional open access (OA) performance. The major data sources include Web of Science, Scopus, Microsoft Academic, and Unpaywall. However, each of these databases continues to update, both actively and retrospectively. This implies the results produced by the proposed process are potentially sensitive to both the choice of data source and the versions of them used. In addition, there remain the issue relating to selection bias in s le size and margin of error. The current work shows that the levels of sensitivity relating to the above issues can be significant at the institutional level. Hence, the transparency and clear documentation of the choices made on data sources (and their versions) and cut-off boundaries are vital for reproducibility and verifiability.
Publisher: Ubiquity Press, Ltd.
Date: 2021
DOI: 10.1629/UKSG.558
Publisher: AOSIS
Date: 27-11-2015
Abstract: A country’s level of exchange risk is closely linked to its financial stability, on a macro-economic scale. South African exchange rates, in particular, have a significant impact on imports, inflation, consumer prices and monetary policies. Consequently, it is imperative for economists and investors to assess accurately the associated exchange risks. Exchange rates, like most financial time series, are leptokurtic and contradict the classical Gaussian assumption. We therefore introduce subclasses of the generalised hyperbolic distribution as alternative models and contrast these with the normal distribution. We conclude that the variance-gamma model is the most robust for describing the log-returns of daily USD/ZAR exchange rates and their related Value-at-Risk (VaR) estimates. The model selection methodologies utilised in our analyses include the robust Kolmogorov-Smirnov test and the Akaike information criterion. Backtesting on the adequacy of VaR estimates is also performed using the Kupiec likelihood ratio test.
Publisher: Open Library of the Humanities
Date: 19-05-2022
DOI: 10.16995/OLH.4809
Abstract: In this article we discuss the collection and nature of ersity data relating to origin (ethnicity, race, nationality, indigeneity), gender/sex and disability in higher education institutional workforces across 24 locations within Africa, Asia, Europe, Latin America, North America and Oceania. The research emerges from the Curtin Open Knowledge Initiative project (n.d.), in which we analyse data relating to published research literature, its open access status, citations and collaborations for institutions, publishers and research funding bodies. Our project explores demographic data relating to workforce ersity and research production we examine who creates knowledge and how ersity is transmitted through research. Collecting and analysing higher education workforce demographic ersity data reveals a global datascape with considerable variation in practices and data collected. The data reflect political and social histories, national and international policies and practices, priorities and funding. The presence and absence of public data provide an opportunity to understand differing national situations and priorities beneath the statistics. We open a conversation about how the concepts of equity, ersity and inclusion differ between groups of countries, which makes global comparisons difficult. By identifying higher education data and gaps, we also encourage institutions and countries to review their workforce demographics and their intersection with research production. Awareness of institutional ersity levels through data analysis can guide institutions towards knowledge openness.
Publisher: Zenodo
Date: 2020
Publisher: OpenEdition Press
Date: 18-04-2020
Publisher: Zenodo
Date: 2017
Publisher: University of Michigan Library
Date: 10-05-2023
DOI: 10.3998/JEP.3398
Abstract: We identify two issues that obstruct the clear assessment of open access publishing performance by academics, librarians, and other stakeholders. Firstly, the current open access categories are difficult to understand and reason about. Secondly, there are no easily accessible tools that allow many countries and institutions to view their open access publishing performance. To address the first issue, we have re-designed the open access categories using descriptive category names rather than opaque colour names, re-organised the categories into a hierarchy to facilitate top-down comprehension, and presented publisher and repository-based open access categories without preferencing one category over the other. To address the second issue, we have developed the COKI Open Access Dashboard, an open-source, public dashboard for measuring and visualising the open access performance of 189 countries and over 7000 institutions. We explore the design decisions underlying the redesigned categories and the dashboard.
Publisher: Humanities Commons
Date: 2018
DOI: 10.17613/VAD9-SC89
Publisher: Zenodo
Date: 2019
Publisher: Clute Institute
Date: 23-12-2014
Abstract: Extreme value theory (EVT) has been widely applied in fields such as hydrology and insurance. It is a tool used to reflect on probabilities associated with extreme, and thus rare, events. EVT is useful in modeling the impact of crashes or situations of extreme stress on investor portfolios. It describes the behavior of maxima or minima in a time series, i.e., tails of a distribution. In this paper, we propose the use of generalised Pareto distribution (GPD) to model extreme returns in the gold market. This method provides effective means of estimating tail risk measures such as Value-at-Risk (VaR) and Expected Shortfall (ES). This is confirmed by various backtesting procedures. In particular, we utilize the Kupiec unconditional coverage test and the Christoffersen conditional coverage test for VaR backtesting, while the Bootstrap test is used for ES backtesting. The results indicate that GPD is superior to the traditional Gaussian and Students t models for VaR and ES estimations.
Publisher: Zenodo
Date: 2017
Publisher: Zenodo
Date: 2015
No related grants have been discovered for Chun-Kai Huang.