Hyperguide for
Logics of Actions and Change

Edited by Erik Sandewall, Department of Computer and Information Science, Linköping, Sweden.

The Hyperguide for Logics of Actions and Change (hg/lac) is a WWW-based structure containing survey and tutorial information about this topic of A.I. research, as well as direct links to key publications in the field. Thus it attempts to combine the functionalities of a traditional "Handbook" in the scientific sense and those of a "Selected papers in ..." volume. The Hyperguide is a joint project by the Esprit working group Logic and Change (LAC), which is directed by Prof. Antonio Porto, Lisbon, Portugal. The work on the Hyperguide is directed by Prof. Erik Sandewall, Linköping, Sweden.

About the hyperguide

Topic: Logics of Actions and Change [scope]
This section is to define the scope of the Hyperguide. The present contents here are provisional. Another introduction to the topic will have to be written eventually, but this file serves as a placeholder and as a proposal for a uniform notation.
Organization of the Hypertext [orghyp]
Explains how this hypertext is organized into sections of a few pages each, with plentiful cross-references between sections and superstructures over them.
How to Reference Material in the Hypermanual [reference]
Catalogue of Authors [authors]
The names of the authors, and cross-links to the sections they have written and to their private home pages.
Who publishes the Hyperguide?

Varieties of logic

Standard multi-sorted FOPC

General
Equality

Nonmonotonic extensions of FOPC

Closure axioms
Default logic
Entailment by model selection
Circumscription

Adaptations for reasoning about change

Fluents, features, the Holds predicate
Fixed, finite object domains

Modal logics

Dynamic logic
Logic of knowledge and belief
Auto-epistemic logic

Non-binary logics

Fuzzy logic
Probabilistic logic

Linear logic

Other...?

Chronicles

Restricted logic syntax
"A" language family
Hypermanual Chronicle Syntax (Choice for this hypermanual)
Transformations and subsumptions between chronicle notations

Semantic concepts

States and state transitions, and their formulation in logic
Timepoint domains and Herbrand situation spaces
Interval time domains
Trajectories
Developments (= histories containing both fluents and actions, resulting from a game)
Static domain constraints (Use (a) as integrity constraints, (b) for ramification i.e. side-effects, and (c) for indirect qualification).
Dynamic domain constraints

Representative examples

[repres-exemp]

Integrated approaches

Each integrated approach is characterized by its choice of logic, its choice of chronicle syntax, and its choice of semantics.

Situation calculus with Herbrand situations

Original situation calculus
Lifschitz, Gelfond, Kartha, et al
Reiter et al

Situation calculus with state situations

Baker

Explicit time described as timepoints

Sandewall et al (Features and fluents)

Explicit time described as intervals

Allen et al
Kowalski et al (Event calculus)

Other

Ontological refinements -- extensions of expressiveness within strict inertia

For each combination of an extension and an integrated approach, either the extension is already present in the approach, or it can/has been realized by some modification of the approach.
Restricted-domain actions (only defined for some starting states)
Branching time
Metric time
Continuous time
Composite actions

Ontological extensions -- extensions of expressiveness beyond strict inertia

Ramification (U, D)
Surprises (S)
Concurrent actions (C)
Natural events (E)
Delayed effects; causation between natural events (L)

Epistemological choices

Strict inertia (K) and strict inertia with limited knowledge about actions (Q)
Misperception: unreliable observations and events(M)

Proposed entailment methods

[entail-methods]

Implementations

Implementations by compilation to monotonic theories [impl-compil]
Implementations by nonmonotonic reasoning algorithms [impl-nonmon]
Other approaches to implementation [impl-other]

Validation and assessment of entailment methods

General principles (Define and discuss concepts of validation, assessment, and postulates)
Upper bounds on range of applicability
Assessments of entailment methods wrt strict inertia
Assessments of entailment methods wrt ramification

Application of entailment methods to representative examples

General principles (Discuss usefulness and limitations of this approach)
Case studies

Notation and terminology

Notational conventions [notn]
Term index [termindex]
ECSTER: European Colloquium on Spatial and Temporal Reasoning
This is the homepage of the Hyperguide.
Latest update: 8.9.1995
Administrated by Erik Sandewall, Linköping University, Sweden. E-mail ejs@ida.liu.se.