The Use of Reference Points in a Sorting Task

The research results presented here draw from data previously reported at SIG-CR 95 (Jorgensen1995b). The theoretical perspectives of categorical perception are used to investigate the nature of similarity judgements in a pictorial environment and to develop a conceptual framework for exploration of the use of reference points in a sorting task. Both Boundary Reference Points and Prototype Reference Points are used by participants in the sorting task. The classification process does not appear to move in a linear or orderly way, and several suggestions concerning the nature of the use of reference points in classificatory behavior do not seem to be supported by this data. Theresults carry implications both for understanding the nature of classificatory behavior and for image indexing and retrieval applications

Classifying Images: Criteria for Grouping as Revealed in a Sorting Task

In the last few decades, technologies such as video-recording and computer-based graphics packages have made images and tools for their creation widely accessible. Advances in technology have made digitization and transmission of images over long distances possible using both network and satellite technology, and these factors have produced a growing number of collections of images stored in digital format. However, providing means of access to the visual content of images has not kept pace with the advances in their production, storage, and transmission

The Exploration by Means of Repertory Grids of Semantic Differences Among Names for Office Documents.

We used repertory grids to investigate the differences in names assigned to a selected list of 11 frequently mentioned office documents. The assumption is that naming reflects a classificatory decision and is based on a complex set of perceived aspects (which we call constructs) of the documents being named. We describe repertory grids as used in this application and summarize the resulting analysis

Optimized intermolecular potential for nitriles based on Anisotropic United Atoms model

An extension of the Anisotropic United Atoms intermolecular potential model is proposed for nitriles. The electrostatic part of the intermolecular potential is calculated using atomic charges obtained by a simple Mulliken population analysis. The repulsion-dispersion interaction parameters for methyl and methylene groups are taken from transferable AUA4 literature parameters [Ungerer et al., J. Chem. Phys., 2000, 112, 5499]. Non-bonding Lennard-Jones intermolecular potential parameters are regressed for the carbon and nitrogen atoms of the nitrile group (–C≡N) from experimental vapor-liquid equilibrium data of acetonitrile. Gibbs Ensemble Monte Carlo simulations and experimental data agreement is very good for acetonitrile, and better than previous molecular potential proposed by Hloucha et al. [J. Chem. Phys., 2000, 113, 5401]. The transferability of the resulting potential is then successfully tested, without any further readjustment, to predict vapor-liquid phase equilibrium of propionitrile and n-butyronitrile

Genetic Resistance to Rhabdovirus Infection in Teleost Fish Is Paralleled to the Derived Cell Resistance Status

Genetic factors of resistance and predisposition to viral diseases explain a significant part of the clinical variability observed within host populations. Predisposition to viral diseases has been associated to MHC haplotypes and T cell immunity, but a growing repertoire of innate/intrinsic factors are implicated in the genetic determinism of the host susceptibility to viruses. In a long-term study of the genetics of host resistance to fish rhabdoviruses, we produced a collection of double-haploid rainbow trout clones showing a wide range of susceptibility to Viral Hemorrhagic Septicemia Virus (VHSV) waterborne infection. The susceptibility of fibroblastic cell lines derived from these clonal fish was fully consistent with the susceptibility of the parental fish clones. The mechanisms determining the host resistance therefore did not associate with specific host immunity, but rather with innate or intrinsic factors. One cell line was resistant to rhabdovirus infection due to the combination of an early interferon IFN induction - that was not observed in the susceptible cells - and of yet unknown factors that hamper the first steps of the viral cycle. The implication of IFN was well consistent with the wide range of resistance of this genetic background to VSHV and IHNV, to the birnavirus IPNV and the orthomyxovirus ISAV. Another cell line was even more refractory to the VHSV infection through different antiviral mechanisms. This collection of clonal fish and isogenic cell lines provides an interesting model to analyze the relative contribution of antiviral pathways to the resistance to different viruses

Image attributes: An investigation

With the rapid expansion in imaging technologies, access to collections of images is a subject of major interest. Indexing systems and computerized retrieval systems for images both need data concerning those image attributes which are typically described. To date, there has been little research upon which to base choices as to which attributes should be included in access systems for images. This research reviews appropriate literature in the psychology and aesthetics of art, image indexing, and cognitive psychology as a foundation for exploratory research investigating attributes typically described in several types of tasks using pictorial images. Participants performed descriptive, categorizing, and searching tasks, and word and phrase data were subjected to content and statistical analyses. Forty-seven image attributes and twelve higher level attribute classes are described. The data suggest that indexing of literal object is of prime significance, as is indexing of the human form and other human characteristics and associated attributes. The concept of location occurs frequently and needs to be addressed. Color is both typically and consistently described and appears to cue attention to certain attributes or areas as well as providing additional information about these attributes. Content/Story and other abstract and affective attributes are also typically described, suggesting that image indexing may benefit by application of concepts associated with indexing of fiction. The strongest factor affecting the image descriptions is the nature of the specific task. The describing tasks and the Sorting and Concept Search Task produced two markedly different distributions of data. The describing tasks appear to mirror a specific item search, whereas the Sorting and Concept Search Task appear to elicit more of a browsing type of behavior. Constructs such as Figure-Ground, prototypes, and schemas are discussed as appropriate contexts for decisions concerning indexing of image attributes. Similarity among images cannot be represented solely by perceptual attributes but must take into account interpretive attributes as well. Term variability is less than might have been expected, suggesting some constraints may exist on the process of communicating about visually perceived data. Future research includes replication of the data with other participants and images, and specification and testing of a set of heuristics to guide decisions in describing the content of visual images for a generalized group of users

Image Access, the Semantic Gap, and Social Tagging as a Paradigm Shift

The recent phenomenon of "social tagging" or "distributed indexing" raises a number of questions regarding long-held beliefs and practices of the classification and indexing community. This workshop paper covers several of these issues, such as locus of authority, control, and meaning, and suggests we may be observing the emergence of a new paradigm of knowledge organization