1 Introduction. - 1. 1 Problem Solving. - 1. 2 Hierarchical Problem Solving. - 1. 3 Generating Abstraction Hierarchies. - 1. 4 Closely Related Work. - 1. 5 Contributions. - 1. 6 Outline. - 2 Problem Solving. - 2. 1 Definition of Problem Solving. - 2. 2 Tower of Hanoi Example. - 2. 3 Problem Solving in PRODIGY. - 3 Hierarchical Problem Solving. - 3. 1 Abstraction Hierarchies. - 3. 2 Hierarchical Problem Solving. - 3. 3 Analysis of the Search Reduction. - 3. 4 Tower of Hanoi Example. - 3. 5 Hierarchical Problem Solving in PRODIGY. - 3. 6 Discussion. - 4 Generating Abstractions. - 4. 1 Properties of Abstraction Hierarchies. - 4. 2 Generating Abstraction Hierarchies. - 4. 3 Tower of Hanoi Example. - 4. 4 Generating Abstractions in ALPINE. - 4. 5 Discussion. - 5 Empirical Results. - 5. 1 Search Reduction: Theory vs. Practice. - 5. 2 Empirical Results for ALPINE. - 5. 3 Comparison of ALPINE and EBL. - 5. 4 Comparison of ALPINE and ABSTRIPS. - 6 Related Work. - 6. 1 Using Abstractions for Problem Solving. - 6. 2 Generating Abstractions for Problem Solving. - 6. 3 Properties of Abstractions. - 7 Conclusion. - 7. 1 Theory of Abstraction. - 7. 2 Generating Abstractions. - 7. 3 Using Abstractions. - 7. 4 Discussion. Language: English