Multiple kernel learning

About: Multiple kernel learning is a research topic. Over the lifetime, 1630 publications have been published within this topic receiving 56082 citations.

Soft Kernel Target Alignment for Two-Stage Multiple Kernel Learning

Abstract: The two-stage multiple kernel learning (MKL) algorithms gained the popularity due to their simplicity and modularity. In this paper, we focus on two recently proposed two-stage MKL algorithms: ALIGNF and TSMKL. We first show through a simple vectorization of the input and target kernels that ALIGNF corresponds to a non-negative least squares and TSMKL to a non-negative SVM in the transformed space. Then we propose ALIGNF+, a soft version of ALIGNF, based on the observation that the dual problem of ALIGNF is essentially a one-class SVM problem. It turns out that the ALIGNF+ just requires an upper bound on the kernel weights of original ALIGNF. This upper bound makes ALIGNF+ interpolate between ALIGNF and the uniform combination of kernels. Our experiments demonstrate favorable performance and improved robustness of ALIGNF+ comparing to ALIGNF. Experiments data and code written in python are freely available at github (https://github.com/aalto-ics-kepaco/softALIGNF).

Combining multiple deep cues for action recognition

Abstract: In this paper, we propose a novel deep learning based framework to fuse multiple cues of action motions, objects and scenes for complex action recognition Since the deep features achieve promising results, three deep representations are extracted for capturing both temporal and contextual information of actions Particularly, for the action cue, we first adopt a deep detection model to detect persons frame by frame and then feed the deep representations of persons into a Gated Recurrent Unit model to generate the action features Different from the existing deep action features, our feature is capable of modeling the global dynamics of long human motion The scene and object cues are also represented by deep features pooling on all the frames in a video Moreover, we introduce an lp-norm multiple kernel learning method to effectively combine the multiple deep representations of the video to learn robust classifiers of actions by capturing the contextual relationships between action, object and scene Extensive experiments on two real-world action datasets (ie, UCF101 and HMDB51) clearly demonstrate the effectiveness of our method

A novel approach to protein structure prediction using PCA or LDA based extreme learning machines

Abstract: In the area of bio-informatics, large amount of data is harvested with functional and genetic features of proteins. The structure of protein plays an important role in its biological and genetic functions. In this study, we propose a protein structure prediction scheme based novel learning algorithms --- the extreme learning machine and the Support Vector Machine using multiple kernel learning, The experimental validation of the proposed approach on a publicly available protein data set shows a significant improvement in performance of the proposed approach in terms of accuracy of classification of protein folds using multiple kernels where multiple heterogeneous feature space data are available. The proposed method provides the higher recognition ratio as compared to other methods reported in previous studies.

Multi-view semantic learning for data representation

Abstract: Many real-world datasets are represented by multiple features or modalities which often provide compatible and complementary information to each other. In order to obtain a good data representation that synthesizes multiple features, researchers have proposed different multi-view subspace learning algorithms. Although label information has been exploited for guiding multi-view subspace learning, previous approaches either fail to directly capture the semantic relations between labeled items or unrealistically make Gaussian assumption about data distribution. In this paper, we propose a new multi-view nonnegative subspace learning algorithm called Multi-view Semantic Learning (MvSL). MvSL tries to capture the semantic structure of multi-view data by a novel graph embedding framework. The key idea is to let neighboring intra-class items be near each other while keep nearest inter-class items away from each other in the learned common subspace across multiple views. This nonparametric scheme can better model non-Gaussian data. To assess nearest neighbors in the multi-view context, we develop a multiple kernel learning method for obtaining an optimal kernel combination from multiple features. In addition, we encourage each latent dimension to be associated with a subset of views via sparseness constraints. In this way, MvSL is able to capture flexible conceptual patterns hidden in multi-view features. Experiments on two real-world datasets demonstrate the effectiveness of the proposed algorithm.

Exploiting multimedia content: a machine learning based approach

Abstract: This thesis explores use of machine learning for multimedia content management involving single/multiple features, modalities and concepts. We introduce shape based feature for binary patterns and apply it for recognition and retrieval application in single and multiple feature based architecture. The multiple feature based recognition and retrieval frameworks are based on the theory of multiple kernel learning (MKL). A binary pattern recognition framework is presented by combining the binary MKL classifiers using a decision directed acyclic graph. The evaluation is shown for Indian script character recognition, and MPEG7 shape symbol recognition. A word image based document indexing framework is presented using the distance based hashing (DBH) defined on learned pivot centres. We use a new multi-kernel learning scheme using a Genetic Algorithm for developing a kernel DBH based document image retrieval system. The experimental evaluation is presented on document collections of Devanagari, Bengali and English scripts. Next, methods for document retrieval using multi-modal information fusion are presented. Text/Graphics segmentation framework is presented for documents having a complex layout. We present a novel multi-modal document retrieval framework using the segmented regions. The approach is evaluated on English magazine pages. A document script identification framework is presented using decision level aggregation of page, paragraph and word level prediction. Latent Dirichlet Allocation based topic modelling with modified edit distance is introduced for the retrieval of documents having recognition inaccuracies. A multi-modal indexing framework for such documents is presented by a learning based combination of text and image based properties. Experimental results are shown on Devanagari script documents. Finally, we have investigated concept based approaches for multimedia analysis. A multi-modal document retrieval framework is presented by combining the generative and discriminative modelling for exploiting the cross-modal correlation between modalities. The combination is also explored for semantic concept recognition using multi-modal components of the same document, and different documents over a collection. An experimental evaluation of the framework is shown for semantic event detection in sport videos, and semantic labelling of components of multi-modal document images.