Towards plug-and-play visual graph query interfaces

Canned patterns ( i.e. , small subgraph patterns) in visual graph query interfaces (a.k.a GUI) facilitate efficient query formulation by enabling pattern-at-a-time construction mode. However, existing GUIS for querying large networks either do not expose any canned patterns or if they do then they are typically selected manually based on domain knowledge. Unfortunately, manual generation of canned patterns is not only labor intensive but may also lack diversity for supporting efficient visual formulation of a wide range of subgraph queries. In this paper, we present a novel, generic, and extensible framework called TATTOO that takes a data-driven approach to automatically select canned patterns for a GUI from large networks. Specifically, it first decomposes the underlying network into truss-infested and truss-oblivious regions. Then candidate canned patterns capturing different real-world query topologies are generated from these regions. Canned patterns based on a user-specified plug are then selected for the GUI from these candidates by maximizing coverage and diversity , and by minimizing the cognitive load of the pattern set. Experimental studies with real-world datasets demonstrate the benefits of TATTOO. Importantly, this work takes a concrete step towards realizing plug-and-play visual graph query interfaces for large networks.

Towards a digital key to the lichens of Italy

Work is in progress for the completion of a computer-aided key to all lichens known to occur in Italy, which will be freely available online, and as a free application for mobile devices. A first example, concerning the lichens of Northern Italy (2.339 infrageneric taxa), is already available online for testing. A computer-generated but manually edited dichotomous key is invoked for all species previously filtered via a multi-entry interface, where several selected characters can be specified in a single step. To optimize the two query interfaces, two different datasets are used, one for the dichotomous, the other for the multi-entry interface.

Online digital library sampling based on query related graph

Purpose Digital library sampling is used to obtain a collection of random literature records from the backend database, which is a crucial issue for a variety of important purposes in many online digital library applications. Digital libraries can only be accessed through their query interfaces. The challenge is how to ensure the randomness of the sample via the autonomous query interface. Design/methodology/approach This paper presents an iterative and incremental approach to obtain samples through the query interface of a digital library. In the approach, a novel graph model, query-related graph, is proposed to transform the flat literature records into a graph structure, and samples are obtained iteratively by traveling the query-related graph. Besides query-related graph, the key components, query generation, termination condition and amending deviation, are also discussed in detail. Findings The extensive experiments over two real digital libraries, ISTIC and IEEE Xplore, show the proposed approach results in a better performance. First, the approach is very effective to obtain high-quality samples which are evaluated by the measure “sample deviation.” Second, the sampling process is very efficient by only submitting fewer random queries. Third, the approach is robust. Research limitations/implications This sampling approach is limited by the query interfaces on a web page. In rare cases (<3 per cent), this approach cannot access query interfaces by sophisticated techniques. Practical implications Digital library sampling is very useful for a variety of important purposes: subject distribution analysis, literature quality evaluation, digital library size estimation, source selection in digital library integration and content freshness evaluation. Social implications Myriads of online digital libraries can be accessed online. Digital library sampling is a useful way to understand digital libraries for many important applications. Originality/value Most of the attributes of a digital library query interface have infinite values, such as keyword attributes, which cannot be handled effectively by the existing sampling approaches.