Actionable 3D subspace clustering from real-world continuous-valued 3D (i.e., object-attribute-context) data promises tangible benefits such as discovery of biologically significant protein residues and profitable stocks, but existing algorithms are inadequate in solving this clustering problem; most of them are not actionable (ability to suggest profitable or beneficial actions to users), do not allow incorporation of domain knowledge, and are parameter sensitive, i.e., the wrong threshold setting reduces the cluster quality. Moreover, its 3D structure complicates this clustering problem. We propose a centroid-based actionable 3D subspace clustering framework, named CATSeeker, which allows incorporation of domain knowledge, and achieves parameter insensitivity and excellent performance through a unique combination of singular value decomposition, numerical optimization, and 3D frequent itemset mining. Experimental results on synthetic, protein structural, and financial data show that CATSeeker significantly outperforms all the competing methods in terms of efficiency, parameter insensitivity, and cluster usefulness.

We derive generalization error (loss) bounds for orthogonal matching pursuit algorithms, starting with kernel matching pursuit and sparse kernel principal components analysis. We propose (to the best of our knowledge) the first loss bound for kernel matching pursuit using a novel application of sample compression and Vapnik-Chervonenkis bounds. For sparse kernel principal components analysis, we find that it can be bounded using a standard sample compression analysis, as the subspace it constructs is a compression scheme. We demonstrate empirically that this bound is tighter than previous state-of-the-art bounds for principal components analysis, which use global and local Rademacher complexities. From this analysis we propose a novel sparse variant of kernel canonical correlation analysis and bound its generalization performance using the results developed in this paper. We conclude with a general technique for designing matching pursuit algorithms for other learning domains.

In order to help users navigate an image search system, one could provide explicit information on a small set of images as to which of them are relevant or not to their task. These rankings are learned in order to present a user with a new set of images that are relevant to their task. Requiring such explicit information may not be feasible in a number of cases, we consider the setting where the user provides implicit feedback, eye movements, to assist when performing such a task. This paper explores the idea of implicitly incorporating eye movement features in an image ranking task where only images are available during testing. Previous work had demonstrated that combining eye movement and image features improved on the retrieval accuracy when compared to using each of the sources independently. Despite these encouraging results the proposed approach is unrealistic as no eye movements will be presented a-priori for new images (i.e. only after the ranked images are presented would one be able to measure a user's eye movements on them). We propose a novel search methodology which combines image features together with implicit feedback from users' eye movements in a tensor ranking Support Vector Machine and show that it is possible to extract the individual source-specific weight vectors. Furthermore, we demonstrate that the decomposed image weight vector is able to construct a new image-based semantic space that outperforms the retrieval accuracy than when solely using the image-features.

This paper gives both general linear model (GLM) and support vector machine (SVM) analyses of an experiment concerned with tonality in music. The two forms of analysis are both contrasted and used to complement each other, and a new technique employing the GLM as a pre-processing step for the SVM is presented. The SVM is given the task of classifying the stimulus conditions (tonal or atonal) on the basis of the blood oxygen level-dependent signal of novel data, and the prediction performance is evaluated. In addition, a more detailed assessment of the SVM performance is given in a comparison of the similarity in the identification of voxels relevant to the classification of the SVM and a GLM. A high level of similarity between SVM weight and GLM t-maps demonstrate that the SVM is successfully identifying relevant voxels, and it is this that allows it to perform well in the classification task in spite of very noisy data and stimuli that involve higher-order cognitive functions and considerably inter-subject variation in neural response.

In the above article, published in Connection Science, Volume 21, Issues 2–3, pp.161–175 (DOI: 10.1080/09540090902733863), the author affiliations appeared as follows: Simon Durranta*, David R. Har...

This special issue on Music, Brain, & Cognition aims to shed light on some of the key issues in current and future music research and technology. Cognitive musicology was envisaged by Seifert (1993...

Kernel methods make it relatively easy to define complex highdimensional feature spaces. This raises the question of how we can identify the relevant subspaces for a particular learning task. When two views of the same phenomenon are available kernel Canonical Correlation Analysis (KCCA) has been shown to be an effective preprocessing step that can improve the performance of classification algorithms such as the Support Vector Machine (SVM). This paper takes this observation to its logical conclusion and proposes a method that combines this two stage learning (KCCA followed by SVM) into a single optimisation termed SVM-2K. We present both experimental and theoretical analysis of the approach showing encouraging results and insights.

We present a general method using kernel canonical correlation analysis to learn a semantic representation to web images and their associated text. The semantic space provides a common representation and enables a comparison between the text and images. In the experiments, we look at two approaches of retrieving images based on only their content from a text query. We compare orthogonalization approaches against a standard cross-representation retrieval technique known as the generalized vector space model.