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Showing papers on "Representation (systemics) published in 2008"


Journal ArticleDOI
TL;DR: How place cells and grid cells may form the basis for quantitative spatiotemporal representation of places, routes, and associated experiences during behavior and in memory is reviewed.
Abstract: More than three decades of research have demonstrated a role for hippocampal place cells in representation of the spatial environment in the brain. New studies have shown that place cells are part of a broader circuit for dynamic representation of self-location. A key component of this network is the entorhinal grid cells, which, by virtue of their tessellating firing fields, may provide the elements of a path integration-based neural map. Here we review how place cells and grid cells may form the basis for quantitative spatiotemporal representation of places, routes, and associated experiences during behavior and in memory. Because these cell types have some of the most conspicuous behavioral correlates among neurons in nonsensory cortical systems, and because their spatial firing structure reflects computations internally in the system, studies of entorhinal-hippocampal representations may offer considerable insight into general principles of cortical network dynamics.

1,641 citations


Journal ArticleDOI
TL;DR: This article re-conceptualize coherence assessment as a learning task and shows that the proposed entity-grid representation of discourse is well-suited for ranking-based generation and text classification tasks.
Abstract: This article proposes a novel framework for representing and measuring local coherence. Central to this approach is the entity-grid representation of discourse, which captures patterns of entity distribution in a text. The algorithm introduced in the article automatically abstracts a text into a set of entity transition sequences and records distributional, syntactic, and referential information about discourse entities. We re-conceptualize coherence assessment as a learning task and show that our entity-based representation is well-suited for ranking-based generation and text classification tasks. Using the proposed representation, we achieve good performance on text ordering, summary coherence evaluation, and readability assessment.

754 citations


Journal ArticleDOI
TL;DR: Recent evidence is presented about how the brain constructs a representation of the surrounding world through whisker-mediated sense of touch and how the transformation of one representation to another is achieved.
Abstract: In the visual system of primates, different neuronal pathways are specialized for processing information about the spatial coordinates of objects and their identity — that is, 'where' and 'what'. By contrast, rats and other nocturnal animals build up a neuronal representation of 'where' and 'what' by seeking out and palpating objects with their whiskers. We present recent evidence about how the brain constructs a representation of the surrounding world through whisker-mediated sense of touch. While considerable knowledge exists about the representation of the physical properties of stimuli — like texture, shape and position — we know little about how the brain represents their meaning. Future research may elucidate this and show how the transformation of one representation to another is achieved.

547 citations


Book ChapterDOI
01 Jan 2008
TL;DR: It is argued that statistical representations play central roles throughout the brain, and that they underlie linguistic forms and situated simulations in the brain's modal systems.
Abstract: This chapter explains that multiple systems represent knowledge. It focuses on two resources of knowledge, believed to have strong empirical support — linguistic forms in the brain's language systems, and situated simulations in the brain's modal systems. Although this chapter focuses on two sources of knowledge, it does not exclude the possibility that other types are important as well. It argues that statistical representations play central roles throughout the brain, and that they underlie linguistic forms and situated simulations. It examines linguistic and modal approaches to the representation of knowledge. It proposes the language and situated simulation (LASS) theory as a preliminary framework for integrating these approaches. It then explores the evidence for the LASS theory, including evidence for dual code theory, Glaser's (1922) revision of dual code theory or the lexical hypothesis, evidence from the laboratories.

481 citations


Journal ArticleDOI
TL;DR: Evidence from chronometric, neuroimaging, developmental and comparative fields is critically reviewed, and a meta-analysis of the neuroim imaging data is supplemented with an integrative overview of each approach to discuss limitations inherent in each approach.

353 citations


Journal ArticleDOI
TL;DR: It appears that information outside the focus of attention can be represented at an abstract level that lacks local detail, but nevertheless carries a precise statistical summary of the scene.
Abstract: The representation of visual information inside the focus of attention is more precise than the representation of information outside the focus of attention. We found that the visual system can compensate for the cost of withdrawing attention by pooling noisy local features and computing summary statistics. The location of an individual object is a local feature, whereas the center of mass of several objects (centroid) is a summary feature representing the mean object location. Three experiments showed that withdrawing attention degraded the representation of individual positions more than the representation of the centroid. It appears that information outside the focus of attention can be represented at an abstract level that lacks local detail, but nevertheless carries a precise statistical summary of the scene. The term ensemble features refers to a broad class of statistical summary features that we propose collectively make up the representation of information outside the focus of attention.

326 citations



Journal ArticleDOI
25 Apr 2008-Science
TL;DR: Undergraduate students may benefit more from learning mathematics through a single abstract, symbolic representation than from learning multiple concrete examples.
Abstract: Undergraduate students may benefit more from learning mathematics through a single abstract, symbolic representation than from learning multiple concrete examples.

263 citations


Patent
27 Feb 2008
TL;DR: In this article, a representation of a user can move with respect to a graphical user interface based on input of the user based on a gesture recognition system, and based on the recognized gesture, the display of the graphical interface is altered and an application control is outputted.
Abstract: A representation of a user can move with respect to a graphical user interface based on input of a user. The graphical user interface comprises a central region and interaction elements disposed outside of the central region. The interaction elements are not shown until the representation of the user is aligned with the central region. A gesture of the user is recognized, and, based on the recognized gesture, the display of the graphical user interface is altered and an application control is outputted.

259 citations


Journal ArticleDOI
TL;DR: A practical method is proposed to implement the multi-word extraction from documents based on the syntactical structure and two strategies as general concept representation and subtopic representation are presented to represent the documents using the extracted multi-words to investigate the effectiveness of using multi- words for text representation on the performances of text classification.
Abstract: One of the main themes which support text mining is text representation; that is, its task is to look for appropriate terms to transfer documents into numerical vectors. Recently, many efforts have been invested on this topic to enrich text representation using vector space model (VSM) to improve the performances of text mining techniques such as text classification and text clustering. The main concern in this paper is to investigate the effectiveness of using multi-words for text representation on the performances of text classification. Firstly, a practical method is proposed to implement the multi-word extraction from documents based on the syntactical structure. Secondly, two strategies as general concept representation and subtopic representation are presented to represent the documents using the extracted multi-words. In particular, the dynamic k-mismatch is proposed to determine the presence of a long multi-word which is a subtopic of the content of a document. Finally, we carried out a series of experiments on classifying the Reuters-21578 documents using the representations with multi-words. We used the performance of representation in individual words as the baseline, which has the largest dimension of feature set for representation without linguistic preprocessing. Moreover, linear kernel and non-linear polynomial kernel in support vector machines (SVM) are examined comparatively for classification to investigate the effect of kernel type on their performances. Index terms with low information gain (IG) are removed from the feature set at different percentages to observe the robustness of each classification method. Our experiments demonstrate that in multi-word representation, subtopic representation outperforms the general concept representation and the linear kernel outperforms the non-linear kernel of SVM in classifying the Reuters data. The effect of applying different representation strategies is greater than the effect of applying the different SVM kernels on classification performance. Furthermore, the representation using individual words outperforms any representation using multi-words. This is consistent with the major opinions concerning the role of linguistic preprocessing on documents' features when using SVM for text classification.

239 citations



Journal ArticleDOI
TL;DR: The effects of representation within the modality of sketching, the effects of functional models, and the retrieval and use of analogies are explored to find that the level of abstraction for the representation of prior knowledge and the represented of a current design problem both affect people's ability to retrieve and use analogous solutions.
Abstract: Design by analogy is a powerful part of the design process across the wide variety of modalities used by designers such as linguistic descriptions, sketches, and diagrams. We need tools to support people's ability to find and use analogies. A deeper understanding of the cognitive mechanisms underlying design and analogy is a crucial step in developing these tools. This paper presents an experiment that explores the effects of representation within the modality of sketching, the effects of functional models, and the retrieval and use of analogies. We find that the level of abstraction for the representation of prior knowledge and the representation of a current design problem both affect people's ability to retrieve and use analogous solutions. A general semantic description in memory facilitates retrieval of that prior knowledge. The ability to find and use an analogy is also facilitated by having an appropriate functional model of the problem. These studies result in a number of important implications for the development of tools to support design by analogy. Foremost among these implications is the ability to provide multiple representations of design problems by which designers may reason across, where the verb construct in the English language is a preferred mode for these representations.

Proceedings ArticleDOI
23 Jun 2008
TL;DR: A time-invariant representation that drastically simplifies learning and recognition by removing time related information such as speed or length of an action is proposed.
Abstract: In this paper, we address the problem of representing human actions using visual cues for the purpose of learning and recognition. Traditional approaches model actions as space-time representations which explicitly or implicitly encode the dynamics of an action through temporal dependencies. In contrast, we propose a new compact and efficient representation which does not account for such dependencies. Instead, motion sequences are represented with respect to a set of discriminative static key-pose exemplars and without modeling any temporal ordering. The interest is a time-invariant representation that drastically simplifies learning and recognition by removing time related information such as speed or length of an action. The proposed representation is equivalent to embedding actions into a space defined by distances to key-pose exemplars. We show how to build such embedding spaces of low dimension by identifying a vocabulary of highly discriminative exemplars using a forward selection. To test our representation, we have used a publicly available dataset which demonstrates that our method can precisely recognize actions, even with cluttered and non-segmented sequences.

Patent
23 May 2008
TL;DR: In this paper, a method and apparatus for creating links between a representation and a realization (e.g., text data and corresponding audio data) is provided, by combining a time-stamped version of the representation generated from the realization with structural information from the representation.
Abstract: A method and apparatus for creating links between a representation, (e.g. text data,) and a realization, (e.g. corresponding audio data,) is provided. According to the invention the realization is structured by combining a time-stamped version of the representation generated from the realization with structural information from the representation. Thereby so called hyper links between representation and realization are created. These hyper links are used for performing search operations in realization data equivalent to those which are possible in representation data, enabling an improved access to the realization (e.g. via audio databases).

Patent
25 Jan 2008
TL;DR: In this paper, a location is specified, e.g., a current location of a mobile device or a user-specified location, and a representation of the location is represented on a map displayed by the mobile device.
Abstract: A location is specified, e.g., a current location of a mobile device or a user-specified location. A representation of the location is represented on a map displayed by the mobile device. A set of contacts having a corresponding address in proximity to the location is determined. A graphical representation of the set of contacts is provided on the map proximate to the one or more corresponding addresses. If the location is a current location of a mobile device, the map can be updated in response to the current location changing with a representation of an updated current location and a representation of an updated set of contacts.


Journal ArticleDOI
TL;DR: It is argued that the ability that characterizes and defines a true cognitive mind, as opposed to a merely adaptive system, is that of building representations of the non-existent, of what is not currently (yet) true or perceivable, ofwhat is desired.
Abstract: Humans and other animals are able not only to coordinate their actions with their current sensorimotor state, but also to imagine, plan and act in view of the future, and to realize distal goals. In this paper we discuss whether or not their future-oriented conducts imply (future-oriented) representations. We illustrate the role played by anticipatory mechanisms in natural and artificial agents, and we propose a notion of representation that is grounded in the agent's predictive capabilities. Therefore, we argue that the ability that characterizes and defines a true cognitive mind, as opposed to a merely adaptive system, is that of building representations of the non-existent, of what is not currently (yet) true or perceivable, of what is desired. A real mental activity begins when the organism is able to endogenously (i.e. not as the consequence of current perceptual stimuli) produce an internal representation of the world in order to select and guide its conduct goal-directed: the mind serves to coordinate with the future.

Proceedings ArticleDOI
12 Jun 2008
TL;DR: A novel unsupervised method for sentence compression which relies on a dependency tree representation and shortens sentences by removing subtrees and it is demonstrated that the choice of the parser affects the performance of the system.
Abstract: We present a novel unsupervised method for sentence compression which relies on a dependency tree representation and shortens sentences by removing subtrees. An automatic evaluation shows that our method obtains result comparable or superior to the state of the art. We demonstrate that the choice of the parser affects the performance of the system. We also apply the method to German and report the results of an evaluation with humans.

Patent
30 Sep 2008
TL;DR: In this paper, a modified representation of the medication treatment parameter profile and the physiological profile based on the detected modification to a segment of the segment of medication treatment parameters is presented. And the first representation of a physiological profile associated with the medication parameter profile is also presented.
Abstract: Method and system including displaying a first representation of a medication treatment parameter profile, displaying a first representation of a physiological profile associated with the medication treatment parameter profile, detecting a modification to a segment of the medication treatment parameter profile, displaying a modified representation of the medication treatment parameter profile and the physiological profile based on the detected modification to the segment of the medication treatment parameter profile, modifying an attribute of the first representation of the medication treatment parameter profile, and modifying an attribute of the first representation of the physiological profile are provided.

Book ChapterDOI
12 May 2008
TL;DR: This paper proposes a system for the detection of functional object classes, based on a representation of visually distinct hints on object affordances (affordance cues), which spans the complete range from tutordriven acquisition of affordance cues, learning of corresponding object models, and detecting novel instances offunctional object classes in real images.
Abstract: Current approaches to visual object class detection mainly focus on the recognition of basic level categories, such as cars, motorbikes, mugs and bottles. Although these approaches have demonstrated impressive performance in terms of recognition, their restriction to these categories seems inadequate in the context of embodied, cognitive agents. Here, distinguishing objects according to functional aspects based on object affordances is important in order to enable manipulation of and interaction between physical objects and cognitive agent. In this paper, we propose a system for the detection of functional object classes, based on a representation of visually distinct hints on object affordances (affordance cues). It spans the complete range from tutordriven acquisition of affordance cues, learning of corresponding object models, and detecting novel instances of functional object classes in real images.


Journal ArticleDOI
TL;DR: These findings indicate that object recognition benefits from associative representations that integrate information about objects' identities and their locations, and directly modulate activation in object-processing cortical regions.
Abstract: Visual context plays a prominent role in everyday perception. Contextual information can facilitate recognition of objects within scenes by providing predictions about objects that are most likely to appear in a specific setting, along with the locations that are most likely to contain objects in the scene. Is such identity-related (semantic) and location-related (spatial) contextual knowledge represented separately or jointly as a bound representation? We conducted a functional magnetic resonance imaging (fMRI) priming experiment whereby semantic and spatial contextual relations between prime and target object pictures were independently manipulated. This method allowed us to determine whether the two contextual factors affect object recognition with or without interacting, supporting a unified versus independent representations, respectively. Results revealed a Semantic Spatial interaction in reaction times for target object recognition. Namely, significant semantic priming was obtained when targets were positioned in expected (congruent), but not in unexpected (incongruent), locations. fMRI results showed corresponding interactive effects in brain regions associated with semantic processing (inferior prefrontal cortex), visual contextual processing (parahippocampal cortex), and object-related processing (lateral occipital complex). In addition, activation in fronto-parietal areas suggests that attention and memory-related processes might also contribute to the contextual effects observed. These findings indicate that object recognition benefits from associative representations that integrate information about objects' identities and their locations, and directly modulate activation in object-processing cortical regions. Such context frames are useful in maintaining a coherent and meaningful representation of the visual world, and in providing a platform from which predictions can be generated to facilitate perception and action.

Patent
15 Sep 2008
TL;DR: In this paper, gesture-based user interaction within an interactive display area is discussed. The display of one or more virtual objects and user interactions with the virtual objects may be further provided Multiple interactive areas may be created by partitioning an area proximate a display into multiple volumetric spaces or zones.
Abstract: Systems and methods for processing gesture-based user interactions within an interactive display area are provided The display of one or more virtual objects and user interactions with the one or more virtual objects may be further provided Multiple interactive areas may be created by partitioning an area proximate a display into multiple volumetric spaces or zones The zones may be associated with respective user interaction capabilities A representation of a user on the display may change as the ability of the user to interact with one or more virtual object changes

Proceedings ArticleDOI
23 Jun 2008
TL;DR: The proposed speed-ups make the system scale to large databases and improve the state-of-the-art in unsupervised learning as well as supervised detection on the challenging PASCALpsila06 multi-class detection tasks for several categories.
Abstract: We present a novel method for the discovery and detection of visual object categories based on decompositions using topic models. The approach is capable of learning a compact and low dimensional representation for multiple visual categories from multiple view points without labeling of the training instances. The learnt object components range from local structures over line segments to global silhouette-like descriptions. This representation can be used to discover object categories in a totally unsupervised fashion. Furthermore we employ the representation as the basis for building a supervised multi-category detection system making efficient use of training examples and out-performing pure features-based representations. The proposed speed-ups make the system scale to large databases. Experiments on three databases show that the approach improves the state-of-the-art in unsupervised learning as well as supervised detection. In particular we improve the state-of-the-art on the challenging PASCALpsila06 multi-class detection tasks for several categories.

Journal ArticleDOI
TL;DR: Methods that could enable a robot to to link sensory information to increasingly abstract concepts (spatial constructs) and the representation that results thereof would enable robots to be more cognizant of their surroundings and yet, compatible to us.

Patent
10 Jul 2008
TL;DR: In this article, a machine learning engine is described that is configured to recognize and learn behaviors, as well as to identify and distinguish between normal and abnormal behavior within a scene, by analyzing movements and/or activities (or absence of such) over time.
Abstract: A machine-learning engine is disclosed that is configured to recognize and learn behaviors, as well as to identify and distinguish between normal and abnormal behavior within a scene, by analyzing movements and/or activities (or absence of such) over time. The machine-learning engine may be configured to evaluate a sequence of primitive events and associated kinematic data generated for an object depicted in a sequence of video frames and a related vector representation. The vector representation is generated from a primitive event symbol stream and a phase space symbol stream, and the streams describe actions of the objects depicted in the sequence of video frames.

Journal Article
TL;DR: The conference was opened by the Minister of Home Affairs Dato Seri Syed Hamid Albar who delivered a keynote address focusing on the theme of the conference as discussed by the authors, which was both critical and timely in view of the fact that Islam is the fastest growing religion and perhaps the most misunderstood religion especially in the West.
Abstract: The conference was opened by the Minister of Home Affairs Dato Seri Syed Hamid Albar who delivered a keynote address focusing on the theme of the conference. The Minister said the conference is both critical and timely in view of the fact that Islam is the fastest growing religion and perhaps the most misunderstood religion especially in the West. He stressed that in the present postmodern time mass media have played and continue to play a significant role in asserting and sustaining stereotypical visions and conceptions about Islam and Muslims. “Evidently, this has given rise to a significant amount of confusion and distorted imagination in the mind of the public at large. Thus, labels such as jihadists, extremists, terrorists and fundamentalists are increasingly becoming more and more popular descriptions of Islam in both the mainstream and the non-mainstream media, particularly in the West,” he added.


Proceedings ArticleDOI
18 Aug 2008
TL;DR: This work proposes opinion frames as a representation of discourse-level associations which arise from related opinion topics and illustrates how opinion frames help gather more information and also assist disambiguation.
Abstract: This work proposes opinion frames as a representation of discourse-level associations which arise from related opinion topics We illustrate how opinion frames help gather more information and also assist disambiguation Finally we present the results of our experiments to detect these associations

01 Jan 2008
TL;DR: In this paper, the authors define a consumer category as a set of products, services, brands, or other marketing entities, states, or events that appear, to the consumer, related in some way.
Abstract: To make sense of the myriad new and existing products and services in the marketplace, consum­ ers construct and use categorical representations to classify, interpret, and understand information they receive about these products and services. We define a consumer category as a set of products, services, brands, or other marketing entities, states, or events that appear, to the consumer, related in some way. We define a categorical representation as information that becomes stored in the cognitive system for a consumer category, and that is later used to process it.! One important use of category representations is during categorization, when consumers use these representations to assign a particular product or service to a consumer category, so that they can understand and draw inferences about it. Consumers might classify a new product as an MP3 player on the basis of prior knowledge about physical or functional features of MP3 players, for example, that MP3 play­ ers store music efficiently, are small in size, and are rectangular in shape. Once the new product is categorized, prior categorical information about MP3 players may also be used to make inferences about unknown attributes or features of the new product, or to form an evaluation of the new product. From a marketing perspective, a number of questions about categorization have been examined that have implications for marketing decision making. For example, how should a new product be