List of Titles

Density-ratio based clustering for discovering clusters with varying densities

- Zhu, Ye, Ting, Kaiming, Carman, Mark

Authors: Zhu, Ye , Ting, Kaiming , Carman, Mark
Date: 2016
Type: Text , Journal article
Relation: Pattern Recognition Vol. 60, no. (2016), p. 983-997
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Description: Density-based clustering algorithms are able to identify clusters of arbitrary shapes and sizes in a dataset which contains noise. It is well-known that most of these algorithms, which use a global density threshold, have difficulty identifying all clusters in a dataset having clusters of greatly varying densities. This paper identifies and analyses the condition under which density-based clustering algorithms fail in this scenario. It proposes a density-ratio based method to overcome this weakness, and reveals that it can be implemented in two approaches. One approach is to modify a density-based clustering algorithm to do density-ratio based clustering by using its density estimator to compute density-ratio. The other approach involves rescaling the given dataset only. An existing density-based clustering algorithm, which is applied to the rescaled dataset, can find all clusters with varying densities that would otherwise impossible had the same algorithm been applied to the unscaled dataset. We provide an empirical evaluation using DBSCAN, OPTICS and SNN to show the effectiveness of these two approaches. © 2016 Elsevier Ltd

Flow and Telepresence contributing to Internet Abuse : Differences according to gender and age

- Stavropoulos, Vasileios, Alexandraki, Kyriaki, Motti-Stefanidi, Frosso

Authors: Stavropoulos, Vasileios , Alexandraki, Kyriaki , Motti-Stefanidi, Frosso
Date: 2013
Type: Text , Journal article
Relation: Computers in Human Behavior Vol. 29, no. 5 (2013), p. 1941-1948
Full Text: false
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Description: Flow describes immersive tendencies to Internet activities, and Telepresence defines the level one is absorbed in his virtual environment. The aim of this study was twofold: (a) to test whether and how Flow and Telepresence may contribute to Internet Abuse and (b) to examine group differences in Internet Abuse, Flow and Telepresence according to gender and age among adolescents. The sample consisted of 1609 adolescents, with a mean age of 16 years old. Internet Abuse was assessed with the Internet Addiction Test (Young, 1998), Flow with the Flow Questionnaire (Chen, Wigand, & Nilan, 1999) and Telepresence with the Presence II questionnaire (Witmer & Singer, 1998). Findings revealed that Flow and Telepresence were related with Internet Abuse with Telepresence positively moderating the effect of Flow. Considering group differences, males were at higher risk of Internet Abuse and were more likely to experience Flow and Telepresence, while older adolescents scored higher only in Telepresence. © 2013 Elsevier Ltd. All rights reserved.

Clustering in large data sets with the limited memory bundle method

- Karmitsa, Napsu, Bagirov, Adil, Taheri, Sona

Authors: Karmitsa, Napsu , Bagirov, Adil , Taheri, Sona
Date: 2018
Type: Text , Journal article
Relation: Pattern Recognition Vol. 83, no. (2018), p. 245-259
Relation: http://purl.org/au-research/grants/arc/DP140103213
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Description: The aim of this paper is to design an algorithm based on nonsmooth optimization techniques to solve the minimum sum-of-squares clustering problems in very large data sets. First, the clustering problem is formulated as a nonsmooth optimization problem. Then the limited memory bundle method [Haarala et al., 2007] is modified and combined with an incremental approach to design a new clustering algorithm. The algorithm is evaluated using real world data sets with both the large number of attributes and the large number of data points. It is also compared with some other optimization based clustering algorithms. The numerical results demonstrate the efficiency of the proposed algorithm for clustering in very large data sets.

Grouping points by shared subspaces for effective subspace clustering

- Zhu, Ye, Ting, Kaiming, Carman, Mark

Authors: Zhu, Ye , Ting, Kaiming , Carman, Mark
Date: 2018
Type: Text , Journal article
Relation: Pattern Recognition Vol. 83, no. (2018), p. 230-244
Full Text: false
Reviewed:
Description: Clusters may exist in different subspaces of a multidimensional dataset. Traditional full-space clustering algorithms have difficulty in identifying these clusters. Various subspace clustering algorithms have used different subspace search strategies. They require clustering to assess whether cluster(s) exist in a subspace. In addition, all of them perform clustering by measuring similarity between points in the given feature space. As a result, the subspace selection and clustering processes are tightly coupled. In this paper, we propose a new subspace clustering framework named CSSub (Clustering by Shared Subspaces). It enables neighbouring core points to be clustered based on the number of subspaces they share. It explicitly splits candidate subspace selection and clustering into two separate processes, enabling different types of cluster definitions to be employed easily. Through extensive experiments on synthetic and real-world datasets, we demonstrate that CSSub discovers non-redundant subspace clusters with arbitrary shapes in noisy data; and it significantly outperforms existing state-of-the-art subspace clustering algorithms.

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Understanding personal use of the Internet at work: An integrated model of neutralization techniques and general deterrence theory

- Cheng, Lijiao, Li, Wenli, Zhai, Qingguo, Smyth, Russell

Authors: Cheng, Lijiao , Li, Wenli , Zhai, Qingguo , Smyth, Russell
Date: 2014
Type: Text , Journal article
Relation: Computers in Human Behavior Vol. 38, no. (September 2014 2014), p. 220-228
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Description: This paper examines the influence of neutralization techniques, perceived sanction severity, perceived detection certainty and perceived benefits of using the Internet for personal purposes on intention to use the Internet at work for personal use. To do so, we draw on a conceptual framework integrating neutralization theory and general deterrence theory. The study finds that both neutralization techniques and perceived benefits have a positive effect on personal use of the Internet. Perceived detection certainty is found to have a negative effect on personal use of the Internet, while the effect of perceived sanctions severity on personal use of the Internet is not significant. The effect of neutralization and perceived benefits are much stronger than perceived detection certainty. The findings suggest that people may think more about neutralization and perceived benefits than they do about costs, when deciding whether to use the Internet at work for personal purposes.
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Eye tracking to investigate cue processing in medical decision making : A scoping review

- Al-Moteri, Modi, Symmons, Mark, Plummer, Virginia, Cooper, Simon J.

Authors: Al-Moteri, Modi , Symmons, Mark , Plummer, Virginia , Cooper, Simon J.
Date: 2017
Type: Text , Journal article , Review
Relation: Computers in Human Behavior Vol. 66, no. (2017), p. 52-66
Full Text: false
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Description: Eye-tracking techniques have been adopted as a research tool for a wide range of applications in healthcare studies. Recently, healthcare researchers have started to show interest in using eye-tracking techniques to study medical decision-making. Mapping the literature pertaining to eye tracking using a systematic approach is valuable at this point to bring together all the studies to date on how medical decision-makers make decisions, and the results may contribute to clinical training. This review follows Arksey and O'Malley's scoping review framework to improve our understanding of visual cue processing in medical decision-making. A diverse range of studies was identified, and the results are presented descriptively to develop a more coherent understanding of different aspects of cue processing and errors in medical decision-making. The review shows the need for more extensive investigations of cue processing and medical decision-making. Crown Copyright (C) 2016 Published by Elsevier Ltd. All rights reserved.

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