Description Logics (DLs) are a class of knowledge representation formalisms that can represent terminological and assertional knowledge using a well-defined semantics. Often, knowledge engineers are experts in their own fields, but not in logics, and require assistance in the process of ontology design. This thesis presents three methods that can extract terminological knowledge from existing data and thereby assist in the design process. They are based on similar formalisms from Formal Concept Analysis (FCA), in particular the Next-Closure Algorithm and Attribute-Exploration. The first of the three methods computes terminological knowledge from the data, without any expert interaction. The two other methods use expert interaction where a human expert can confirm each terminological axiom or refute it by providing a counterexample. These two methods differ only in the way counterexamples are provided.

The main contribution of this thesis is a comprehensive analysis of the influence of changes in the population structure on local communities, in particular with respect to the provision of publicly provided goods. The focus is placed on the consequences of two of the major processes of demographic change, namely aging and shrinking. The three main chapters of this contribution consider the effects at the local level from both a theoretical and an empirical perspective. The first model focuses on the influence of population aging on the provision of local publicly provided goods, when the young population may relocate. When aging advances, gerontocracies and social planners substitute publicly provided goods aimed at the mobile young for publicly provided goods for the elderly. However, due to fiscal competition, gerontocracies will provide even more of the publicly provided good for the young than the social planner. The second model considers in a two-period setting, the interaction of a shrinking population when the investments made by the previous generation are long lived. The laissez-faire and welfare maximizing outcomes are computed for two cases; first with no costs of upkeep and second for the case when costs of upkeep accrue. A comparison of the solutions shows that public provision for the first generation is inefficiently low in laissez-faire when there are no costs of upkeep. However, if costs of upkeep accrue, the laissez-faire outcome for the intergenerational publicly provided good may be too high. Chapter four contains an empirical analysis. In a two-stage analysis the efficiency of the provision of child care services in municipalities is evaluated in the German State of Saxony. First, the results of the Data Envelopment Analysis (DEA) show substantial efficiency differences; the median municipality is up to 28% inefficient. In a second stage bootstrapped truncated regression, determinants of the inefficiency are identified. Explanatory variables such as an uncompensated mayor or a larger share of over 65-year-olds significantly increase inefficiency.