1 CIS607, Fall 2004 Semantic Information Integration Presentation by Xiaofang Zhang Week 7 (Nov. 10)

2 Questions from Homework 5 What’s the difference between this approach and other approaches? – The paper is doing a nice job proving the properties of ontology mapping and matching problem. But it seems what they propose – middleware data model – is exactly what some others are doing. I.e. other approaches are also mapping data in different ontologies into an intermediate one and then go from there. – Along the same line of question one, when the authors talk about representing correspondence/relations between difference data in their data model, they said they assume having “ a SINGLE data forest (that can be viewed as the union of data forests) ”. And also they distinguish data from different sources by putting source (e.g. F1, F2) into the labels. This looks very similar with the idea of having a merged onotology with namespace distinguish sources in paper by Dou etal. What is the relationship between these two approaches? -- Xiangkui – How is the strategy of translation in this paper different then the one from Dou et al? How is it similar? -- Paea

3 Questions from Homework 5 (cont ’ d) Is there a standard (better) way to do translation? – With all these research efforts being made to translate data from disparate sources, each using their own preferred format, wouldn't it be worthwhile to spend efforts on coming up with some standards (similar to IETF protocols) and getting away with all the translation problem? – Each paper on translation/merging/alignment presents a new approach to solve the concerned problem. Is there some common underlying mechanism that these approaches use or are they just ad-hoc solutions? -- Vikash

4 Questions from Homework 5 (cont ’ d) About the algorithm. – I don’t see how labeling input and output vertices in the merged trees is considered a restriction – it seems like necessary bookkeeping to me. Is it because additional metadata is added to the forest which is irrelevant to the source and target data? -- Kevin – Can the validity of rules be checked as they are being composed, i.e. are the rulesets provably correct in what actions they will take since they are defined formally? -- Julian

5 Questions from Homework 5 (cont ’ d) Other questions about this paper: – Data sources must be in a tree-like (forest-like) format, correct? An example of data that is not in such a format would be? – Paea – This seems like a good solution for creating data warehouses and database translation. Is this method implemented in other software? Has the W3TRANS software been successful? -- Kevin - How do the execution times of W3TRANS compare to other systems? -- Julian