Updates in RDF stores have recently been standardised in the SPARQL 1.1 Update specification. However, computing answers entailed by ontologies in triple stores is usually treated orthogonal to updates. Even the W3C's recent SPARQL 1.1 Update language and SPARQL 1.1 Entailment Regimes specifications explicitly exclude a standard behaviour how SPARQL endpoints should treat entailment regimes other than simple entailment in the context of updates. In this paper, we take a first step to close this gap. We define a fragment of SPARQL basic graph patterns corresponding to (the RDFS fragment of) DL-Lite and the corresponding SPARQL update language, dealing with updates both of ABox and of TBox statements. We discuss possible semantics along with potential strategies for implementing them. We treat both, (i) materialised RDF stores, which store all entailed triples explicitly, and (ii) reduced RDF Stores, that is, redundancy-free RDF stores that do not store any RDF triples (corresponding to DL-Lite ABox statements) entailed by others already. / Series: Working Papers on Information Systems, Information Business and Operations

Package party, implemented in the R system for statistical computing, provides basic classes and methods for recursive partitioning along with reference implementations for three recently-suggested tree-based learners: conditional inference trees and forests, and model-based recursive partitioning. / Series: Research Report Series / Department of Statistics and Mathematics

One of the cornerstones of the R system for statistical computing is the multitude of contributed packages making an extremely broad range of statistical techniques and other quantitative methods freely available. This study investigates which factors are the crucial determinants responsible for the participation of the package authors in the R project. For this purpose a survey was conducted among R package authors, collecting data on different types of participation in the R project, three psychometric scales (hybrid forms of motivation, work design characteristics, and values), as well as various specie-demographic factors. These data are analyzed using item response theory and generalized linear models, showing that the most important determinants for participation are a hybrid form of motivation and the knowledge characteristics of the work design. Other factors are found to have less impact or influence only specific aspects of participation. (authors' abstract) / Series: Research Report Series / Department of Statistics and Mathematics