Research and Data Reusability

By data exchangeability we mean the ability of two entities, i.e., data author and data user, to exchange meaningful data sets. Data exchangeability is a prerequisite for data reuse. During the data exchange process, especially when data are moving between scientific disciplines, three types of "heterogeneity" must be addressed.

First, heterogeneity between the native data/query language (of the data author) and the target data/query language (of the data user). When this heterogeneity is resolved, we say that syntactic exchangeability between the two entities has been achieved.

Second, heterogeneity between the data models adopted by data author and user to represent information objects. When this heterogeneity is resolved, we say that structural exchangeability between the two entities has been achieved.

Third, heterogeneity between the domain of discourse of data author and user. When this heterogeneity is resolved, we say that semantic exchangeability between the two entities has been achieved.

These three levels of exchangeability, i.e., syntactic, structural, and semantic allow a meaningful exchange of data between the data author and user. However, the three levels of exchangeability do not guarantee that the data user is able to reuse the exchanged data; they only constitute a necessary but not sufficient condition for effective data reuse.

The main concept enabling data exchangeability is mediation. This concept has been used to cope with many dimensions of heterogeneity, spanning data language syntaxes, data models, and semantics. The mediation concept is implemented by a mediator, which is a software device capable of establishing exchangeability by resolving heterogeneities.