CfP: 9th International Rule Challenge 2015 part of the

March 28, 2015 12:11 PM
The RuleML 2015 Challenge is one of the highlights at RuleML 2015 Conference which seeks to provide a competition among innovative rule-oriented applications, aimed at both the research and industrial side. Take the chance to get a 500/300/200 USD for the three best RuleML Rulebases of 2015.

Key themes of the RuleML 2015 Challenge include, but are not limited to the following:

  • Demos related to the RuleML 2015 Track Topics
  • Rule-based Event Processing and Stream Reasoning
  • Rule learning
  • Distributed rule bases and rule services
  • Reports on industrial experience about rule systems
  • Real cases and practical experiences


Rule modeling, rule authoring, rule engines and applications

  • - Innovative UX for rule modeling, rule editors, NLP powered rule authoring
  • - Cloud-based applications for rule storage and execution
  • - Translators between different rule languages, open source rule engines
  • - Semantic Web rule applications using social media data
  • - Rule-based applications for crowdsourcing

RuleML Rulebase Competition

RuleML Inc announces three awards (of $500, $300, $200) for the three best RuleML Rulebases of 2015. This year's rulebases are solicited in Reaction RuleML 1.0 or 1.02, Deliberation RuleML 1.01 or 1.02 or Consumer RuleML 1.02.

Rule-based Recommender Systems for the Web of Data

  • - rule learning algorithms applied on recommender problems
  • - using the linked open data cloud for feature set extension


Like in the previous edition, RuleML Inc. will offer prizes:

RuleML Challenge Award

RuleML Challenge Runner-up Award

Three best RuleML Rulebase Awards

Four prizes in the Rule-based Recommender Systems for the Web of Data track

Submission Guidelines

High quality, original papers, potentially referencing online material, and ranging between 5-15 pages can be submitted at

All submissions must conform with the LNCS format (
To ensure high quality, submitted papers will be carefully peer-reviewed by 3 PC members based on clarity and significance of objectives and demonstration of results.

The annual International Web Rule Symposium (RuleML) is an international conference on research, applications, languages and standards for rule technologies. RuleML is the leading conference to build bridges between academia and industry in the field of rules and its applications, especially as part of the semantic technology stack.
  • Conference URL:
  • Conference hashtag:
  • Organization Website:
  • RuleML Blog & Social Mediazine:

Keynotes at: Thom Fruehwirth, Constraint Handling Rules

March 18, 2015 9:17 AM
Thom Frühwirth is the designer of the programming language Constraint Handling Rules (CHR) and author of the book by the same name. He has co-authored two leading textbooks on constraint programming and reasoning that became standard references for the research area. He has published more than 170 research papers in declarative programming and logical reasoning.

Constraint Handling Rules (CHR) is a concurrent committed-choice constraint logic programming language. It consists of guarded rules that transform multi-sets of atomic formulas (constraints) until exhaustion. In CHR, one can describe algorithms in a compact declarative way. It can directly embed many rule-based formalisms and systems.

The clean logical semantics of CHR ensures that several desirable properties hold for proper CHR programs for free (such as incrementality). It also facilitates non-trivial program analysis (such as confluence). In particular, operational equivalence of terminating programs is decidable.

Last but not least, we present typical academic and commercial applications from the international CHR community. They range from stock broking to a world record attempt in robot sailing.

The annual International Web Rule Symposium (RuleML) is an international conference on research, applications, languages and standards for rule technologies. RuleML is the leading conference to build bridges between academia and industry in the field of rules and its applications, especially as part of the semantic technology stack.
  • Conference URL:
  • Conference hashtag:
  • Organization Website:
  • RuleML Blog & Social Mediazine:

CfP: Rule-based Recommender Systems Challenge at

March 16, 2015 11:18 AM
The challenge has two focus areas: (1) rule learning algorithms applied on recommender problems and (2) using the linked open data cloud for feature set extension. It uses a semantically enriched version of the MovieLens dataset. In addition to the standard metrics, the challenge aims to assess the understandability of the rule set generated by the participating rule-based systems.
A challenge of, August 2-5, 2015 Berlin
Important dates
  • Paper and result submission: May 23, 2015
  • Author Notification: June 6, 2015
  • Challenge: 3-5 Aug, 2015
The Task
The participating systems are requested to find and recommend a limited set of 5 items that best match a user profile.
  • The participants will be provided with a semantically enriched version of the MovieLens dataset.
  • It is mandatory that a participating solution either uses the linked open data cloud to further extend the feature set or is a rule-based classifier. Both options simultaneously are preferred.
  • A scorer is provided by the organizers so that the participants can check their progress.
  • Challenge submission will consist of the set of additional recommendations (top-5 movies) for each user from the train dataset and a file containing the rules that lead to the prediction (rule based classifiers only, PMML RuleSet model preferred but not required).
Judging and Prizes
Four prizes, totalling to 500 USD, will be given:
  • best recommender performance will be given to the paper with the highest score in the evaluation (main prize)
  • most understandable ruleset (only rule-based submissions eligible)
  • best aggregate diversity
  • most original approach, selected by the Challenge Program Committee with the reviewing process

Rule Challenge 2015 proceedings will be published as CEUR Proceedings and indexed by SCOPUS.

  • Jaroslav Kuchař (Czech Technical University, Prague)
  • Tommaso di Noia (Politecnico di Bari, Italy)
  • Heiko Paulheim (University Mannheim, Germany)
  • Tomáš Kliegr (University of Economics, Prague)
The annual International Web Rule Symposium (RuleML) is an international conference on research, applications, languages and standards for rule technologies. RuleML is the leading conference to build bridges between academia and industry in the field of rules and its applications, especially as part of the semantic technology stack.
  • Conference URL:
  • Conference hashtag:
  • Organization Website:
  • RuleML Blog & Social Mediazine:

Keynotes at: Michael Genesereth,The Herbrand Manifesto-Thinking Inside the Box

March 9, 2015 5:25 PM
Michael Genesereth is an associate professor in the Computer Science Department at Stanford University. He received his Sc.B. in Physics from M.I.T. and his Ph.D. in Applied Mathematics from Harvard University. Genesereth is most known for his work on Computational Logic and applications of that work in Enterprise Management, Electronic Commerce, and Computational Law.
The traditional semantics for First Order Logic (sometimes called Tarskian semantics) is based on the notion of interpretations of constants. Herbrand semantics is an alternative semantics based directly on truth assignments for ground sentences rather than interpretations of constants. Herbrand semantics is simpler and more intuitive than Tarskian semantics; and, consequently, it is easier to teach and learn. Moreover, it is more expressive. For example, while it is not possible to finitely axiomatize integer arithmetic with Tarskian semantics, this can be done easily with Herbrand Semantics. The downside is a loss of some common logical properties, such as compactness and completeness. However, there is no loss of inferential power. Anything that can be proved according to Tarskian semantics can also be proved according to Herbrand semantics. In this presentation, we define Herbrand semantics; we look at the implications for research on logic and rules systems and automated reasoning; and we assess the potential for popularizing logic.

RuleML 2015 Deadline Extension (March 18, 2015)

March 4, 2015 11:28 AM
After receiving several requests the Organization Committee decieded to extend the full paper submission deadline by two weeks to March 18, 2015. So, there is more time to finish your papers without undue haste. You might even consider a new paper entry if some related research became ready just now. Other RuleML2015 sub-events have later deadlines

Business Cases and Technologies for Rules in Industry (CfP)-

January 28, 2015 1:56 PM
With the increased importance of big data for improving operational performance in all sectors of industry, the role of rule technologies has become ever more manifest (and even critical). Indeed, if Data assets have been recognized as the "new oil", then Rule technologies should be introduced for the most important processing steps in generating value from data.

For example, event-condition rules enable the detection of an anomaly state in the process execution by processing huge streams of sensor data. However, not only the creation and execution of such rules, but also their maintenance and refinement require a systematic approach, provided usually through rule management methodologies and systems. On the other hand the industry is still not completely aware of the importance of such approaches for an efficient utilization of rules in the era of big data. Therefore, there is a need for industry to share, exploit, and learn about the use of rules and rule technologies for solving real life business problems. The proposed industry track aims to be a forum for all sectors of industry (and the corresponding public sectors) to address such needs.

Incentives for industry participation in this track include:

  • Present own results / solutions for use of rule technologies in business settings
  • Learn about new trends in rule technologies, and how they can be used to address business problems
  • Learn about new trends in other domains (like Big data, Internet of Things) that influence the application of rule technologies in industry
  • Exchange experiences about business cases and use of rules
  • Compete for a RuleML award for best business case for use of rules technologies


The track seeks two types of submissions in LNCS format:

  • Extended abstracts of up to 2 pages
  • Short papers of up to 8 pages

Irrespective of the type, the submissions must follow the following structure / template:

  1. Business case - explain the business case and the value proposition
  2. Technological challenges - explaining why the business case challenge is difficult to solve using traditional technologies
  3. Rule-based solution - technical details, esp. the usage of rules
  4. Results - the benefits of the solution, including improvement of KPIs
  5. Importance and impact - describe the importance of the solution for business/technology

Topic-wise any rules-related topics are welcome as long as they follow the above structure.

The submissions will be peer-reviewed. Selected best industry papers will be published in the RuleML Springer LNCS Proceedings and all other accepted industry papers will be published in the RuleML CEUR proceedings. The papers must be submitted via RuleML submission system at and selecting the track "RuleML 2015 - Industry Track".

Besides presenting their business case papers, selected authors of industry track papers, among others, will be invited to participate in a panel related to the use of rules and rule technologies in business cases.


Paper Submission: April 30, 2015
Author Notification May 15, 2015
Camera Ready May 30, 2015
Industry Track dates: 3-5 Aug, 2015


Nenad Stojanovic, Nissatech Innovation Centre, Serbia,
Dumitru Roman, SINTEF, Norway,
Mark Proctor, Redhat, UK,


The Sad State Concerning the Relationships between Logic, Rules and Logic Programming

January 13, 2015 3:48 PM

Confusions about the relationships between logic, rules and logic programming are endemic in the world of computing. Here are some quotes from Paul Thagard’s popular textbook [15], Mind, Introduction to Cognitive Science, which show how bad things are:

Rules are if-then structures such as: IF you pass forty Arts courses, THEN you graduate with a B.A. These structures are very similar to the conditionals discussed in chapter 2, but they have different representational and computational properties. (Page 43)

Unlike logic, rule-based systems can also easily represent strategic information about what to do. Rules often contain actions that represent goals, such as IF you want to go home for the weekend, and you have the bus fare, THEN you can catch a bus. (Page 45)

In logic-based systems the fundamental operation of thinking is logical deduction, but from the perspective of rule-based systems the fundamental operation of thinking is search.  (Page 45)

Rule-based problem solving sounds a lot like logical deduction, but it differs in that much more attention is paid to strategies for applying the right rules at the right time. (Page 47)

I am particularly sensitive to the claim about the difference between deduction and search, because two of my earliest papers [3, 4] investigated the relationship between deduction and search. In my 2011 book [5], I discuss Thagard’s various claims about logic and rules, and I argue that there are three varieties of production rules:

  1. Rules like IF you pass forty Arts courses, THEN you graduate with a B.A. These are logic programming clauses, used to reason forwards from conditions to conclusions.
  2. Rules like IF you want to go home for the weekend, and you have the bus fare, THEN you can catch a bus. These are “forward chaining” rules, used to simulate backward reasoning with logic programming clauses, such as, you go home for the weekend, if you have the bus fare, and you catch a bus.
  3. Rules like IF you are hungry THEN eat something. These are reactive rules, used to make the conclusion of the rule true whenever the condition of the rule becomes true.

In the book, I argue that reactive rules have a more general syntax than logic programming clauses, and they are also more fundamental. But, curiously, almost all of the examples of rules in Thagard’s book are of the first and second variety. So, contrary to Thagard’s intentions, most of his arguments against logic and in favour of rules are actually arguments for logic programming.

In the book (Chapter 8), I argue that reactive rules (or maintenance goals) are the “driving force of life”. Consider, for example, the following AgentSpeak [14] reactive rule (or “plan”), which specifies a waste-collecting robot’s mission in life:

+location(waste, X):location(robot, X) & location(bin, Y) <- pick(waste); !location(robot, Y); drop(waste).

The rule is triggered whenever waste appears at a location and the robot is at the same location.  The robot then picks up the waste, moves to the bin location and drops the waste. The direction of the arrow <- is motivated by the seeming similarity of such plans to logic programming clauses. But it is opposite to the direction that is needed to give the plan a logical meaning. For example:

If there is waste at location X at time T1, and the robot is at location X at T1 and the bin is at location Y at T1, then the robot picks up the waste at time T1+1, the robot goes to location Y at some time T2 (after T1) and the robot drops the waste into the bin at time T2+1.


There are two problems with such rule-based systems: How to specify the logic of reactive rules, and how to relate the logic of reactive rules to the logic of logic programs.

Abductive logic programming (ALP) [2, 6] provides a candidate solution: Given a Horn clause logic program P, a set of integrity constraints I (representing reactive rules) and candidate assumptions A (representing all possible state-transforming actions), the computational task is to find a collection of actions Δ ⊆ A, such that I is true in the minimal model of P ⋃ Δ. For more general logic programs, the minimal model needs to be replaced by a more general canonical model, such as the perfect model.

The ALP solution also needs a way to generate state transitions. It is common to use the event calculus [13] for this purpose. But this involves using a frame axiom, to reason explicitly that a fact (or fluent) that is true in a state continues to be true in subsequent states until it is terminated by an action or external event. This kind of reasoning is not computationally feasible in the general case. However, Fariba Sadri and I have shown [7, 8, 9, 10, 11, 12] that state transitions can also be generated in the usual, more efficient way that uses destructive updates, without affecting the model theoretic semantics. We call the resulting framework LPS, for Logic-based Production System, because it was motivated by the goal of giving a logical semantics to production systems.

In some of our recent papers, for the sake of simplicity, we have focussed on a Kernel sublanguage, KELPS [10, 11], which consists of reactive rules alone. It was only recently that we realised that the model-theoretic semantics of KELPS is similar to that of MetaTem, which was being developed by other researchers in our logic programming group at Imperial College in the late 1980s.

MetaTem is a modal temporal logic language in which all program statements have the form past and present formula implies present or future formula. For example,

    hungry ==> (buy_food ∧ О cook_food ∧ О О eat)

At a sufficiently abstract level, the semantics of MetaTem is identical to that of LPS and KELPS: Computation is the process of attempting to generate a model that makes the program true. But in MetaTem, models are possible world structures, generated using frame axioms. In KELPS/LPS, programs are represented in a non-modal language with explicit time, and models are classical models in which all facts are time stamped and contained in a single structure.  For example, in KELPS, the MetaTem program above would be approximated by a reactive rule of the form:

    hungry(T) --> buy_food(T+1) ∧ cook_food(T+2) ∧ eat(T+3)

where buying food occurs after (instead of at the same time as) becoming hungry.

I believe that KELPS and LPS are more powerful and more efficient than MetaTem. But the  MetaTem  approach was on the right track. Back in the 1980s, because it was so different from logic programming and because it was formulated in modal logic, I couldn’t see the bigger picture.

Having finally understood MetaTem after more than 25 years, although it was developed under my own nose, I am not surprised that other researchers also have problems in seeing connections that are staring them in the face. Nonetheless, it is still a sad state of affairs.



  1. Barringer, H., Fisher, M., Gabbay, D., Gough, G., & Owens, R. (1990, January). METATEM: A framework for programming in temporal logic. In Stepwise Refinement of Distributed Systems Models, Formalisms, Correctness (pp. 94-129). Springer Berlin Heidelberg, Available at
  2. Kakas, A. C., Kowalski, R., Toni, F. (1998). The Role of Logic Programming in Abduction, Handbook of Logic in Artificial Intelligence and Programming 5, Oxford University Press, 235-324.
  3. Kowalski, R. (1970), "Search Strategies for Theorem-proving", in Machine Intelligence 5,  (eds. B. Meltzer and D. Michie), Edinburgh University Press, 1970, pp. 181-201, Available at
  4. Kowalski, R. (1972), "And-or Graphs, Theorem-proving Graphs and Bi-directional Search", in Machine Intelligence 7,  (eds. B. Meltzer and D. Michie), Edinburgh University Press, 1972, pp. 167-94. Available at
  5. Kowalski, R. (2011) Computational Logic and Human Thinking: How to be Artificially Intelligent, Cambridge University Press. Available at
  6. Kowalski, R. and Sadri, F. (1999) From Logic Programming Towards Multi-agent Systems, Annals of Mathematics and Artificial Intelligence, Vol. 25, 391-419.
  7. Kowalski, R. and Sadri, F. (2009) Integrating Logic Programming and Production Systems in Abductive Logic Programming Agents. In Proceedings of the Third International Conference on Web Reasoning and Rule Systems, Chantilly, Virginia, USA.
  8. Kowalski, R. and Sadri, F. (2010) An Agent Language with Destructive Assignment and Model-Theoretic Semantics, In: Dix J., Leite J., Governatori G., Jamroga W. (eds.), Proc. of the 11th International Workshop on Computational Logic in Multi-Agent Systems (CLIMA), 200-218.
  9. Kowalski, R. and Sadri, F. (2011) Abductive Logic Programming Agents with Destructive Databases, Annals of Mathematics and Artificial Intelligence, Vol. 62, No. 1, 129-158.
  10. Kowalski, R. and Sadri, F. (2012) A Logic-Based Framework for Reactive Systems, Rules on the Web: Research and Applications, In: A. Bikakis and A. Giurca (Eds.) Proceedings of the 6th International Symposium on Rules: Research Based and Industry Focused (RuleML 2012),  Springer-Verlag, LNCS 7438, pp. 1–15. See also
  11. Kowalski, R. and Sadri, F. (2014)  A Logical Characterization of a Reactive System Language, In: A. Bikakis et al. (Eds.) Proceedings of the 8th International Web Rule Symposium (RuleML 2014), LNCS 8620, Springer International Publishing Switzerland, pp. 22-36. See also
  12. Kowalski, R. and Sadri, F. (2014) Model-theoretic and operational semantics for Reactive Computing. To appear in New Generation Computing.
  13. Kowalski, R., Sergot, M. (1986) A Logic-based Calculus of Events. New Generation Computing, Vol. 4, No.1, 67—95. Available at
  14. Rao, A. (1996) AgentSpeak (L): BDI agents speak out in a logical computable language. Agents Breaking Away, 42-55. Available at
  15. Thagard, P. (2005) Mind: Introduction to cognitive science. MIT press.


Call for Papers: The 9th International Web Rule Symposium (RuleML 2015)

December 18, 2014 12:35 PM
The annual International Web Rule Symposium (RuleML) is the leading international event in the field of rules and their applications. RuleML 2015, the ninth event in this series, will be held in Berlin, Germany, August 3-5 in conjunction with the Conference on Automated Deduction (CADE), the Conference on Web Reasoning and Rule Systems (RR) and the Reasoning Web Summer School (RW).
RuleML 2015 will host multiple tracks on Complex Event Processing, Existential Rules and Datalog+/-, Industry, Legal Rules and Reasoning and Rule Learning, as well as hosting the 9th International Rule Challenge and the 5th RuleML Doctoral Consortium.
  • Co-located with:
    CADE 2015 RR 2015 Reasoning Web 2015 FOMI 2015
  • Sponsored by:
  • In cooperation with:
    TCSEM CSW Group Berlin


RuleML 2015 welcomes practitioners, interested in the theory and applications of rules in academic research, industry, engineering, business and other diverse application areas. It provides a forum for stimulating co-operation and cross-fertilization between the many different communities focused on the research and development of rule-based systems.
The symposium's areas of research and development have helped drive rapid progress in technologies for practical rule and event processing in distributed enterprise, intranets, and open distributed environments. Industry practitioners, rule-system providers, users of rules, technical experts and developers, and researchers who are exploring foundational issues, developing systems and applications, or using rule-based systems are invited to share ideas, results, and experiences.


The conference has 5 special tracks, as well as general sessions. The tracks are:

  • Complex Event Processing
  • Existential Rules and Datalog+/
  • Legal Rules and Reasoning
  • Rule Learning
  • Industry

We invite high-quality submissions related (but not limited) to the special tracks and within the general theme of the conference.

Track Topics

Complex Event Processing (Main theme: Uncertainty Handling in Complex Event Processing)

  • Scalable CEP under uncertainty
  • Visual analytics for CEP systems
  • Distributed CEP under uncertainty
  • Real-world applications of CEP
  • Event forecasting under uncertainty
  • Privacy issues in CEP
  • Multi-scale temporal aggregation of events
  • Benchmarks and testbeds for CEP
  • Machine learning for event processing and forecasting

Existential Rules and Datalog+/

  • Decidability paradigms for existential rules
  • Consistent query answering
  • Reasoning and querying
  • Query Rewriting
  • Nonmonotonic reasoning
  • Query Optimization
  • Probabilistic reasoning
  • Ontology Languages
  • Data and knowledge integration and exchange
  • Ontology-based Data Access System
  • Conceptual modeling
  • Descriptions and applications
  • Semi-structured data, graph databases and (Semantic) Web data

Legal Rules and Reasoning

  • Learning from legal texts
  • Modeling normative rules
  • Reguratory compliance by rules
  • Modeling legislation
  • XML, standards for legal documents
  • Legal ontology
  • Semantic Web in Legal Domain
  • Legal Open Data and Rules
  • Reasoning about normative rules
  • Normative rules extraction by natural language processing

Rule Learning

  • Inductive rule learning
  • Classification rules
  • Association rules
  • Learning rules for the semantic web
  • Preference rules
  • Rule-based recommender systems
  • Relational learning
  • Learning business rules
  • Descriptive rule learning
  • Predictive rule learning

Industry Track

The RuleML 2015 Industry Track targets businesses and the private sector interested in sharing, exploring, and learning about the use of rules and rule technologies for solving real life business problems. For further information about the Industry Track topics and submission see:

General Topics (not limited to)

  • Rules and automated reasoning
  • Rule-based policies, reputation, and trust
  • Reaction rules
  • Rules and the Web
  • Rule discovery from data
  • Fuzzy rules and uncertainty
  • Logic programming and nonmonotonic reasoning
  • Non-classical logics and the Web (e.g modal, especially deontic and epistemic, logics)
  • Hybrid methods for combining rules and statistical machine learning techniques (e.g., conditional random fields, Probabilistic Soft Logic)
  • Rule transformation and extraction
  • Vocabularies, ontologies, and business rules
  • Rule markup languages and rule interchange formats
  • Rule-based distributed/multi-agent systems
  • Rules, agents, and norms
  • Rule-based communication, dialogue, and argumentation models
  • Rule-based data integration
  • Vocabularies and ontologies for pragmatic primitives (e.g. speech acts and deontic primitives)
  • Pragmatic web reasoning and distributed rule inference / rule execution
  • Rules in online market research and online marketing
  • Applications of rule technologies in health care and life sciences
  • Rules and Human Language Technology
  • Industrial applications of rules
  • Rules and business process compliance checking
  • Standards activities related to rules
  • Rules and social media
  • General rule topics

Student Travel Support

Student Travel Support of EUR 500 will be provided for the two best student (first author) submissions. For a paper to be considered, its first author must be a student. Proof of studentship will be required at time of registration. More detailed information on how to apply will be sent to authors of accepted papers through Easychair.

Important Dates

  • Abstract Submission February 25, 2015
  • Paper Submission March 4, 2015
  • Notification May 4, 2015
  • Camera Ready May 18, 2015
  • Symposium Dates August 3-5, 2015

Submission guidelines

(except for the Industry Track - the guidelines for the Industry Track can be found at

Papers must be original contributions written in English and must be submitted at EasyChair ( as:

For all Tracks and general topics:

  • Full Papers (15 pages in the proceedings)
  • Short Papers (8 pages in the proceedings)

For submission to a particular track please select that particular track/category. To submit under the general topics simply select the "General RuleML track" category.

All papers must have at least three keywords identifying the main topics of the paper.

Please upload all submissions in LNCS format ( To ensure high quality, submitted papers will be carefully peer-reviewed by 3 PC members based on originality, significance, technical soundness, and clarity of exposition. Selected papers, including those accepted for the special tracks will be published in book form in the Springer Lecture Notes in Computer Science (LNCS) series (

Short papers may contain 1 extra page maximum for which there is a charge of US$200, while for long papers you are allowed 2 extra pages maximum for EACH of which there is a charge of US$200.