In current distributed systems, the notion of mobility is emerging in many forms and applications. Mobility arises naturally wireless computing since location users changes as they move. Besides computing, software mobile agents are another popular form moving objects. Locating objects, i.e., identifying their location, central to computing. We present a comprehensive survey various approaches problem storing, querying, updating objects The fundamental techniques underlying proposed...

Result diversification has recently attracted much attention as a means of increasing user satisfaction in recommender systems and web search. Many different approaches have been proposed the related literature for problem. In this paper, we survey, classify comparatively study various definitions, algorithms metrics result diversification.

Preferences have been traditionally studied in philosophy, psychology, and economics applied to decision making problems. Recently, they attracted the attention of researchers other fields, such as databases where capture soft criteria for queries. Databases bring a whole fresh perspective study preferences, both computational representational. From representational perspective, central question is how we can effectively represent preferences incorporate them database querying. look at...

Recommending packages of items to groups users has several applications, including recommending vacation tourists, entertainment friends, or sets courses students. In this paper, we focus on a novel aspect package-to-group recommendations, that fairness. Specifically, when recommend package group people, ask recommendation is fair in the sense every member satisfied by sufficient number package. We explore two definitions fairness and show for either definition problem finding most NP-hard....

Abstract We increasingly depend on a variety of data-driven algorithmic systems to assist us in many aspects life. Search engines and recommender among others are used as sources information help making all sort decisions from selecting restaurants books, choosing friends careers. This has given rise important concerns regarding the fairness such systems. In this work, we aim at presenting toolkit definitions, models methods for ensuring rankings recommendations. Our objectives threefold:...

To deal with the frequent, foreseeable and variable disconnections that occur in a mobile environment, we introduce flexible, two-level consistency model. Semantically related or closely located data are grouped together to form cluster. While all inside cluster mutually consistent, degrees of inconsistency allowed among at different clusters. take advantage predictability disconnections, accommodate mobility, configuration is dynamic. We allow transactions exhibit certain tolerance for...

Recently, result diversification has attracted a lot of attention as means to improve the quality results retrieved by user queries. In this paper, we propose new, intuitive definition diversity called DisC diversity. A diverse subset query contains objects such that each object in is represented similar and are dissimilar other. We show locating minimum an NP-hard problem provide heuristics for its approximation. also adapting subsets different degree diversification. call operation...

Mobile computing introduces a new form of distributed computation in which communication is most often intermittent, low-bandwidth, or expensive, thus providing only weak connectivity. We present replication scheme tailored for such environments. Bounded inconsistency defined by allowing controlled deviation among copies located at weakly connected sites. A dual database interface proposed that addition to read and write operations with the usual semantics supports operations. In contrast...

The popularity of the Web as a universal access mechanism for network information has created need developing Web-based DBMS client/server applications. However, current commercial applet-based approaches accessing database systems offer limited flexibility, scalability, and robustness. We propose new framework distributed to based on Java-based mobile agents. supports lightweight, portable, autonomous clients well operation slow or expensive networks. implementation using aglet workbench...

Peer-to-peer (p2p) systems are attracting increasing attention as an efficient means of sharing data among large, diverse and dynamic sets users. The widespread use XML a standard for representing exchanging in the Internet suggests using describing shared p2p system. However, imposes new challenges related to supporting advanced querying beyond simple keyword-based retrieval. In this paper, we focus on management issues processing setting, namely indexing, replication, clustering query...

Traditionally, the refreshment of data warehouses has been performed in an off-line fashion. Active Data Warehousing refers to a new trend where are updated as frequently possible, accommodate high demands users for fresh data. In this paper, we propose framework implementation active warehousing, with following goals: (a) minimal changes software configuration source, (b) overhead source due nature propagation, (c) possibility smoothly regulating overall environment principled way. our...

To handle the overwhelming amount of information currently available, personalization systems allow users to specify that interests them through preferences. Most often, have different preferences depending on context. In this paper, we introduce a model for expressing such contextual Context is modeled as set multidimensional attributes. We formulate context resolution problem (a) identifying those qualify encompass state query and (b) selecting most appropriate among them. also propose an...

Bias in online information has recently become a pressing issue, with search engines, social networks and recommendation services being accused of exhibiting some form bias. In this vision paper, we make the case for systematic approach towards measuring To end, discuss formal measures quantifying various types bias, outline system components necessary realizing them, highlight related research challenges open problems.

In this paper, we focus on labeled graphs that evolve over time. Given a sequence of graph snapshots representing the state at different time instants, seek to find most durable matches an input pattern query, is, exist for longest period The straightforward way address problem is by running state-of-the-art algorithm each snapshot and aggregating results. However, large networks approach computationally expensive, since all have be generated snapshot, including those appearing only once. We...

Graphs offer a generic abstraction for modeling entities and the interactions relationships between them. Most real-world graphs, such as social cooperation networks, evolve over time, exploring their evolution may reveal important information. In this paper, we present TempoGRAPHer, system analyzing visualizing of temporal attributed graphs. TempoGRAPHer supports both attribute aggregation. It also allows graph exploration by identifying periods significant growth, shrinkage, or stability....

Counterfactuals have been recognized as an effective approach to explain classifier decisions. Nevertheless, they not yet considered in the context of clustering. In this work, we propose use counterfactuals clustering solutions. First, present a general definition for model-based that includes plausibility and feasibility constraints. Then consider counterfactual generation problem k-means Gaussian assuming Euclidean distance. Our takes input factual, target cluster, binary mask indicating...

In this paper, we present a comprehensive survey on the pervasive issue of medical misinformation in social networks from perspective information technology. The aims at providing systematic review related research and helping researchers practitioners navigate through fast-changing field. Research spans multiple disciplines, but technical surveys rarely focus domain. Existing provide broad insights for various stakeholders lack deep dive into computational methods. This fills that gap by...

It is expected that in the near future, tens of millions users will have access to distributed information systems through wireless connections. The technical characteristics medium and resulting mobility both data resources consumers raise new challenging questions regarding development appropriate for mobile environments. In this paper, we report on such a system. First, describe general architecture system main considerations our design. Then, based these considerations, present support...