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"STIMULUS AGENTS: AN ALTERNATIVE,FRAMEWORK FOR COMPUTER-AIDED
DECISION MAKING"
by
Albert AN GEHRN*
N° 9I/54/TM
* Assistant Professor of Information Systems, INSEAD, Boulevard de Constance,Fontainebleau 77305 Cedex, France.
Printed at INSEAD,Fontainebleau, France.
Stimulus Agents: An alternative Framework forComputer-aided Decision Making
Albert A. AngehrnINSEAD, European Institute of Business Administration
F-77300 Fontainebleau, France
Today's Decision Support Systems (DSS), Expert Systems, Executive InformationSystems, Group DSS and similar computer-based tools are based on conceptualframeworks developed in the early 80s. New frameworks capturing the latestresearch tendencies in the DSS field are needed as a basis for the next generationof decision support tools. The alternative DSS framework illustrated in this paperis rooted in the metaphor of a "Decision Making Arena" in which decisionmakers define and explore their problems interactively under the continuousstimulus (help, guidance and criticism) of dynamic "Agents". The role of suchelectronic agents is to recreate a team-work environment. Accordingly, theyassume in turn the role of information providers, servants, experts or mentors.By intervening in the arena on explicit request of the decision maker as well asunexpectedly, dynamic agents illustrate a "supporting by challenging" approachto computer-aided decision making.
Keywords: Decision making, DSS, Agents, Human-Computer Interaction.
Address: INSEAD,European Institute of Business AdministrationBd de ConstanceF-77305 Fontainebleau Cedex, France
Phone: 33 - 1 - 60 72 40 00Fax: 33 - 1 - 60 72 40 49Bitnet: Angehrn@Freiba5l
Stimulus Agents: An alternative Framework forComputer-aided Decision Making
Albert A. ANGEHRN
INSEAD, European Institute of Business AdministrationFontainebleau, France
Today's Decision Support Systems (DSS), Expert Systems, Executive InformationSystems, Group DSS and similar computer-based tools are based on conceptualframeworks developed in the early 80s. New frameworks capturing the latestresearch tendencies in the DSS field are needed as a basis for the next generationof decision support tools. The alternative DSS framework illustrated in this paperis rooted in the metaphor of a "Decision Making Arena" in which decisionmakers define and explore their problems interactively under the continuousstimulus (help, guidance and criticism) of dynamic "Agents". The role of suchelectronic agents is to recreate a team-work environment. Accordingly, theyassume in turn the role of information providers, servants, experts or mentors.By intervening in the arena on explicit request of the decision maker as well asunexpectedly, dynamic agents illustrate a "supporting by challenging" approachto computer-aided decision making.
Computer-aided Decision Making: Ambitions and OutcomesA first milestone in the field of computer-aided decision making was the seminalwork on Management Decision Systems of Scott Morton [1971], who defined suchsystems as "an aid for those management problems that are large, unstructured,non-programmable (in Simon's [1960] terms) and that involve managementjudgment." Several books and research papers followed in the early 80s (see e.g.Keen and Scott Morton [1978], Bonczek et al. [1981], Sprague and Carlson [1982])providing alternative, but similar definitions of the type of system which will begrouped here under the label "DSS", including also in this concept tools such asExpert Systems, Knowledge-based or Intelligent Decision Systems (DSS exploitingArtificial Intelligence techniques), Executive Information Systems (DSSaddressing the needs of top managers), Group and Negotiation Support Systems(DSS supporting teams of cooperative and non-cooperative decision makers). Astestified by recent surveys, the DSS concept has had a rapid growth in research aswell as in practice (cf. Eom and Lee [1990] for an extensive list of DSS applicationsdescribed in academic and business journals). In spite of that, computer-aideddecision making is still far from being considered as a "completed" project. It isnot difficult to encounter constructive criticism coming both from the academicand the practitioners' world, addressing the limitations of current conceptualframeworks and questioning the effective applicability and usefulness of today'sDSS.
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Designing Effective DSS: Traditional ApproachesOur present day view of how to develop DSS is the result of almost twenty yearsof research and experiences. In addition, the field has inherited concepts as wellas techniques, technologies and methodologies from disciplines such as DecisionScience, Operations Research, Computer Science, Data Management andInformation Systems, and - to a minor extent - from Psychology, CognitiveScience, Human Factors and Organizational Studies. As a result, current DSS areconceived and designed on the basis of a few traditional frameworks (cf. the twomajor ones proposed by Sprague and Carlson [1982] and by Bonczek et al. [1981])and employ several types of computer techniques and technologies ranging fromNeural Networks and Logic Programming to Hypermedia and other advancedHuman-Computer Interaction techniques (see e.g. Trippi and Turban [1989],Kimbrough et al. [1990], Jones [1991], Angehrn and Liithi [1990]). In addition,questions concerning the management of DSS implementation in organizationsas well as their evaluation and justification [Keen 1981] have been largelyaddressed and explored.
A common point on which all DSS converge, independent from the frameworkadopted, the technology used and the strategy selected by designers andimplementors, is the shared objective of "providing support" to human decisionmakers. This is a basic, but key consideration in that it clearly specifies the generalcontext DSS are supposed to address (the context of man-machine collaboration)and the type of situations in which the use of these systems can be beneficial (so-called "ill-" or "semi-structured" situations in which neither man alone normachine alone can work efficiently and effectively in an autonomous way).
Even if the term "providing support" can be and has been interpreted in severalways, it is possible to identify two broad, but distinct classes in which the majorityof current DSS can be categorized. Systems belonging to these two classes arecalled in this context "Vehicle" and "Toolbox" DSS. The first group of systems arethose resulting from the strong - and not often explicitly stated - designassumption that "Given a specific decision situation, an expert (or group ofexperts) is able to recognize the decision-maker's needs in terms of (1) how torepresent the decision situation (problem structuring), and (2) how to proceed inorder to identify the "best" solution (problem-solving strategy)."
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flexibilityguidanceprovidedsupport
To this first class belong all the DSS whose kernel consists of a specific problem-solving technique, e.g. an optimization algorithm, or an Artificial Intelligenceheuristic. Typical representatives of this category are so-called MCDSS (MultiCriteria DSS) [Eom 1989], i.e. systems based on specific Decision Theory models(e.g. Elimination by Aspects [Tversky 1972], Analytical Hierarchy Process [Saaty1986], Multi Attribute Utility Theory [Keeney and Raiffa 1976]) which providetheir users with a particular way of representing decisions as well as with a pre-determined strategy (usually supported by a given algorithm) for exploring theproblem and identifying "solutions". Systems equipped with more than onesingle method or problem-solving technique (i.e. containing a Model Base and arelated Model Management System [Blanning 1989]) can still be consideredVehicle DSS as long as they are based on the assumption mentioned above, i.e.on a model of problem representation and exploration which is determined apriori by the DSS designer. For all these DSS, the use of the term "vehicle" isjustified by the fact that such systems are basically a technological means allowingdecision-makers to easily access specific problem-solving techniques ormethodologies (generally based on a theoretic model of rationality).
On the other hand, Toolbox DSS are not based on any normative model ofdecision making. They do not impose any specific problem-structuring approachnor do they supply a particular problem-solving technique. The assumptionunderlying Toolbox DSS is that the objective of "providing support" can beachieved by simply delivering a set of tools which decision makers can employ instructuring, representing and exploring their problems. Typical DSS belonging tothis class are spreadsheet programs and so-called DSS generators [Sprague andCarlson 1982] providing a loosely coupled set of tools such as modelinglanguages, statistical functions, graphic packages, simulation and optimizationsubroutines, etc.
low low
Figure 1: "Vehicle" vs "Toolbox" DSS. Guidance vs Flexibility.
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Although almost every present day DSS falls into one of the two classesintroduced above, these simply represent two extremes of a still weakly exploredpalette of possibilities to "provide support" (see Figure 1). Vehicle DSSpropose/impose a specific methodology to the decision maker. They deliverstrong guidance at the cost of flexibility (constraining decision makers both in thechoice of problem representations and problem analysis strategies). On the otherhand, Toolbox DSS are generally flexible in terms of enabling their users toemploy a variety of approaches and tools for their decision tasks (cf. Huber [1983]),but provide little guidance on both problem representation and exploration.
In accordance with other authors - Keen [1987] describes a similar classification ofDSS into "active" and "passive" systems, and Silver [1990] proposes a broad andclear analysis of the two concepts of "decision guidance" and "systemrestrictiveness" - a way to increase the level of support provided by DSS consistsin identifying alternative frameworks leading to the design of new systems notbelonging to the traditional categories of Vehicle and Toolbox DSS. The guidance-flexibility antithesis illustrated above has led to the formulation of such analternative framework: A conversational, agent-based approach to DSS.
The Conversational Framework for Decision Support (CFDS): MotivationIn general terms, the introduction of new conceptual frameworks is appropriatewhenever an important objective cannot be attained by applying existingframeworks. The specific objective underlying the introduction of theConversational Framework is to "enhance creativity in collaborative human-computer problem solving".
The first issue, creativity-enhancement, is an old, still unachieved goal of DSSresearchers which has been recently brought up again by authors like Elam andMead [1990] and discussed for instance by Angehrn [1990] in the specific context ofdesigning MCDSS based on a "facilitation/stimulus" cycle involving problemstructuring/restructuring as well as the process of solution generation,questioning and justification. In addition, creativity-enhancement is not meantto be confined to the search for the correct path in a complex maze (the problem-solving phase [Newell and Simon 1972]) but also to the "maze-building" process[Dery 1983] in which a decision maker identifies or sets objectives, chooses thevalues to maintain and represents/conceptualizes problems accordingly.
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a: Individual problemrepresentation and
b: Continuous stimuli.
DM Arena
The second issue, collaborative human-computer problem solving, has alsorecently gained in importance in the DSS research field. For instance, at leasteight of the papers presented at a recent DSS Conference [ISDSS 90] discuss so-called Active, Adaptive, Symbiotic or Intelligent DSS (see e.g. Jakob et al. [1990] foran overview of these concepts and the related literature). The suggestedprototypes and the presented studies attempt to relate this new research directionin the DSS field to the theory of "inquiring systems" introduced by Churchman[1971], to implementation issues such as the use of (distributed) ArtificialIntelligence techniques, to theoretical constructs such as "cognitive coupling"[Fitter and Sime 1980], to Human-Computer Interaction studies, as well as to bothmachine-internal and decision-makers' learning processes.
The specific objective of the next sections is to illustrate a conceptual frameworkintegrating these research efforts and leading to the design of a new generation ofDSS for which existing frameworks are not sufficient anymore.
CFDS: OverviewThe basic difference between the Conversational Framework and previouslyproposed ones is that the former is conceptually based on a socio-political ratherthan on a techno-rational approach to supporting human decision-making.Whilst traditional frameworks mainly conceive DSS as a means for deliveringspecific problem-solving methodologies or technologies, the ConversationalFramework views DSS as an opportunity to recreate - via a computer - a naturalsetting in which problems are exposed, discussed and explored: The team-workenvironment (see Figure 2).
(Agent A
Figure 2: The "team-work" environment underlying CFDS and its threecomponents: User(s), Decision-Making Arena and Stimulus Agents.
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Conceptually as well as operationally, this framework differs from previousapproaches to DSS in three main dimensions: (D1) The overall objectives of thesystem, (D2) the approach adopted in order to deliver "decision support", and(D3) the technical means employed at the level of the DSS architecture. Table 1summarizes the Conversational Framework along these three dimensionsallowing a direct comparison with the characteristics of the two DSS types(vehides and toolboxes) discussed in the first part of the paper.
Conversational Vehicle Toolbox
Overall Objective facilitate and stimulatereflective learning
provide normativeguidance
provide flexibleenvironments
Decision SupportApproach
conversational(team-work centered)
prescriptive(system centered)
passively flexible(user centered)
Technical Means Decision-Making Arenaand Stimulus Agents
specific methodologyand/or technique
variety ofloosely coupled tools
Table 1: The Conversational Framework: Overview and Comparison.
(Dl) The Underlying Decision Making Model: The "Arena" MetaphorThe Conversational Framework is rooted in the assumption that decisionsupport can be provided by facilitating and stimulating reflective learning.
In accordance with Boxer [1980], we suppose that (1) decision-makers areintentional beings capable of original thought, that (2) such thought arises fromthe decision-makers' attempts to give expression to their intentions or sense ofpurpose, and that (3) this expression takes on an external form. In more concreteterms, reflective learning implies the existence of an explicit locus and of a set of
tools which facilitate decision-makers in incrementally "giving expression" totheir individual mental models, translating them into an "external form" andreflecting about them, generating "original thought."
On the other hand, it has been demonstrated that cognitive biases [Evans 1989],limitations of human information-processing capabilities [Hogarth 1987] and,more generally, bounded individual knowledge and rationality [Simon 1960]relevantly reduce the positive effects of free, i.e. completely unguided andunsupervised, reflective learning. Complementing individual reflectiveprocesses with external stimuli can be identified as an additional condition toeffective decision support.
(D1)
(D2)
(D3)
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breakdownsstimuli
Arena Level
Agents Level
evolving problemrepresentations (PR)and corresponding
4 444 44 • solutions (S) .1000nu 000000000000000000 I oo
User Level
problem view& analysis strategy
( USER ) Representation &
Analysis Tools Reflective Learning
alternative viewpoints on:• problem representation• problem analysis strategy
objectives, knowledge (data, models,rules, etc.) and communication facilities
Arena Analysis(static & dynamic) (AGENT ))
The above considerations determine the decision-making model underlying theConversational Framework (see Figure 3). In this model, decision-making isviewed as a process driven by (i) the analytical and reflective learning skills of thedecision maker, and (ii) the dynamic intervention of a set of stimulus agents. Thethird key element is the so-called "Decision-Making Arena" (DMA).Conceptually, the role of the Arena is to provide a neutral, blackboard-like [Nii1986] "common ground" on which all the actors involved in the process canrepresent, analyze and discuss a decision situation. In particular, the DMAprovides the explicit locus needed to support reflective learning (User Level -Arena Level loop) as well as to provide continuous stimuli for this process(Agents Level - Arena Level loop).
Figure 3: The decision-making process and the "Arena" metaphor for DSS.
In summary, the DMA fulfils three basic functions. First, it provides a concreteenvironment in which decision-makers can translate their thoughts. Second, itsupports reflective learning by enabling decision-makers to continuouslycompare their individual mental models with self-developed, explicit and henceanalyzable representations. Third, it determines an interaction space in whichother agents can intervene to stimulate the ongoing process.
The state of a DMA at any given time during the decision-making process can beformally represented through the pair (PR, S). The first element of the pair, PR,
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stands for a specific problem representation, i.e. for an explicit model of thedecision situation expressed through a set of entities, relationships andconstraints. The second element, S, stands for the specific course of action("solution proposal") mapped into the arena which is currently considered by thedecision maker. In these terms, the pair (PR, S) represents a dynamic, commonproblem view shared by the agents involved in the decision-making process.
The decision-making process itself can be mapped at the Arena Level into asequence of state transitions (PR, S) (PR', S'), where each step involves a newproblem representation PR', the identification of a more satisfactory solution S',or both. In its initial phase, starting e.g. from an "empty" arena (PR = 0, S = 0),the process is mainly driven by the user's objective to depict his or her currentproblem view, i.e. to map it into the arena. This "positioning phase" is thenfollowed by a "discussion phase" in which the content of the arena is analyzed,re-organized and updated until the task-related breakdowns [Winograd andFlores 1986] occurring during the process are solved, and a form of stability (cf. theconcept of cognitive equilibrium in [Zeleny 1989]) is obtained.
(D2) A Step beyond Toolbox and Vehicle DSS: Passive vs Active CouplingFrom an architectural point of view, the components of a DSS based on theConversational Framework are similar to those of a Toolbox DSS includingseveral knowledge sources such as databases, structured collections of analyticaltechniques, inference mechanisms, etc. (see Zachary [1986] for an overview ofdecision support techniques). Examples of such systems are commerciallyavailable DSS generators as well as spreadsheet packages including database accessmethods, risk analysis or optimization routines.The main difference between such conventional DSS and systems based on theConversational Framework does not lie in the availability of multiple knowledgesources, but in the way the different components of the man-machine systemcollaborate throughout a decision-making process (passive vs active coupling).
Passive coupling of decision support techniques is concerned only with enablingthe user to access sophisticated tools (data-, model-, rule-bases, etc.) via flexiblemodeling environments. Active coupling goes beyond providing access. Tostimulate reflective learning as described in the previous section, the differentknowledge sources stored in the DSS have to interact in a conversational stylerepresenting a mid-way point between the prescriptive/authoritative styleadopted in Vehicle DSS and the non-restrictive but somehow laxistic approachunderlying Toolbox DSS.
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In order to achieve this goal, decision support components based on specificfactual, technical or methodological knowledge are individually encapsulatedinto so-called Stimulus Agents equipped with:
(1) the capability of assessing dynamically the suitability of taking the initiativeand interrupting the ongoing, user-driven process, and
(2) the capability of intervening in the Decision-Making Arena providing -depending on their specific knowledge - new facts, viewpoints, suggestionsof different problem representations or reasons for adopting alternativeanalysis strategies.
Figure 4 illustrates a general architecture for encapsulating decision supportknowledge and tools within Stimulus Agents. This architecture results fromassociating the knowledge source available to each single agent (AKS module)with a so-called Agent's Behavior Component (ABC module). The latter modulerepresents an extension of the traditional way in which decision support toolsand techniques are integrated in DSS. In fact, the role of the ABC module is to
regulate the way the agent dynamically conveys its specific knowledge in theDMA. Its four slots (see Figure 4) consist of structured collections of rulesgoverning the behavior of the agent in response to events generated in the DMAby the decision-maker or by other agents. These rules determine (i) themechanisms used by the agent to analyze the current DMA state in order toidentify opportunities for interventions (Arena Analysis Slot), (ii) the criteriaused to evaluate the suitability and frequency of individual or concertedinterventions (Objectives and Coordination Slot), and (iii) the procedures used bythe agent to intervene in the arena and carry on a dialogue with the decision-maker (Communication Slot).
Agent's Interactionin the Decision-Making Arena
Agent's Behaviour Component(ABC)
Agent's Knowledge Source(AKS)
(as enerall fresent ra
...
...„...1"Objectives" Slot"Communication" Slot
"Coordination" Slot"Arena Analysis" Slot
Specific type of I
• Information(Data, Documents, Graphics, etc.)
• Information Processing Mechanism(Algorithms, Inference Techniques, etc.)
Figure 4: Agent's Architecture.
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In summary, the difference between passive and active coupling in DSS can beexplained in terms of presence (or absence) of the two key componentsunderlying the Conversational Framework, i.e. Stimulus Agents and DMA. Thisis illustrated in Table 2. According to [Te'erd and Ginzberg 1991], computer-aideddecision processes can be seen from the viewpoint of a collaboration between twoparties, a human and a computer-based one. Table 2 reflects the level of involve-ment of each party in shaping the decision-making process (passive vs. active)observable in different DSS types. From this perspective, Toolbox DSS areprincipally passive systems requiring the user to actively shape the process. Atthe other extreme, Vehicle DSS tend to confine users to a passive role, as thechoice of a suitable problem representation and analysis strategy are delegated tothe system, which virtually acts as a guiding expert.
User's role
System's roleActive Passive
Active Conversational DSS
C'v---0---
Vehicle DSS
Passive Toolbox DSS-41M11.-.
System enhancement witha Decision-Making Arena
Encapsulation of decisionsupport tools withinStimulus Agents
Table 2: Levels of involvement in shaping the decision-making process.
On the other hand, DSS based on the Conversational Framework fall into theactive-active category and represent both an extension and a generalization of theother two DSS types. For instance, Vehicle DSS can be seen as ConversationalDSS in which the decision process is dominated by a single, computer-based,authoritative agent. In this particular case, the presence of a DMA is not requiredgiven the absence of an authentic dialogue between the user and the system.
As illustrated in Table 2, both Vehicle and Toolbox DSS can be upgraded byrespectively extending these systems with one of the two key components - DMAand Stimulus Agents - introduced above. In the specific case of a Vehicle DSS, theaddition of a DMA turns out to be a necessary condition for enabling DSS users(as well as other potential actors) to actively participate in shaping the decision-making process.
(D3) Stimulus Agents: A Taxonomy
Stimulus Agents of the type described in section (D2) can be classified into threemain categories depending on their stimulus domain, i.e. on the specific phase ofthe decision-making process they contribute to shape (see Table 3).
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The first type of agents, Structuring Agents, provide stimuli to change, refine andreflect on a given problem representation. For instance, the function of 'story-teller' agents is to widen the decision-maker's current problem view. 'Mappingspecialists' provide alternative ways of representing and/or visualizing problems,and 'inquirers' force the user to reflect about the correctness, the completenessand the relevance of the model currently mapped in the Decision-Making Arena.The second type of agents, Solving Agents, are responsible for helping thedecision-maker to identify solutions for a given, provisionally fixed, problemrepresentation. This task can be fulfilled by encapsulating classical model-based,data-based and knowledge-based tools (e.g. OR and AI techniques as well as accessmechanisms to data and document bases) into active agents as described in thethe first part of this section. Finally, the role of the third type of agents, ProcessAgents, is to analyze, monitor and - if required - guide the decision-makingprocess. Concrete examples of the three types of Stimulus Agents listed in Table 3are provided in the next section in connection with an overview of currentresearch efforts.
Agent Type Stimulus domain Examples
Problem (re)structuring, framing process. • story tellersStructuring Agents Stimulate PR PR transitions • mapping specialists
given the Arena state (PR, S). • inquirers
Problem solving, choice process. • model-based agentsSolving Agents Stimulate S 5 transitions for a given PR • data-based agents
given the Arena state (PR, S) • knowledge-based agents
Supervision of decision-making process. • process expertsProcess Agents Stimulate next state transition(s) given • bias experts
a history (PRo,S3) (PRI,S1)... (PR.,S.) • methodology advisers
Table 3: A Taxonomy of Agents.
Major Research Areas
DSS with the characteristics described in this paper are still in a prototype stage.Currently, there are two major research areas related to the operationalization ofthe Conversational Framework. These are:
(1) Studies related to the encapsulation of decision support knowledge inStimulus Agents of the type described in sections (D2) and (D3);
(2) Studies related to the design of Decision Making Arenas with thecharacteristics described in section (D1).
Studies related to the integration of dynamic agents in DSS have been initiated byresearchers in the DSS sub-field called "Active DSS" [Manheim 1988; Mili 1990].Raghavan and Chang [1989] are two of the first authors who relate the concept of"Active DSS" with the idea of integrating multiple agents in a DSS. Their workhas strongly contributed to the developMent of computational frameworks andof a series of prototypes [Raghavan and Chang 1989; Raghavan 1990]demonstrating the feasibility and the advantages of systems in which different"machine-based personalities" dynamically influence the user. Research relatedto Stimulus Agents acting as advisors/assistants during a problem-solvingprocess is reported in Manheim et al. [1990]. The authors describe a prototypesystem for production planning and scheduling which is able to workindependently of user direction, to experiment with possible schedule changes,and to report on the interesting variations it has identified. A further importantrole assumed by Stimulus Agents, critiquing, has been investigated in AI [Cohenand Feigenbaum 1982] and has already found several applications, for instance inthe fields of human-computer interaction [Fischer and Mastaglio 1989] andlearning processes [Thomas 1976]. Two further types of Stimulus Agents, 'model-based agents' and 'story-tellers', are currently under study in a project targetingthe extension of an existing MCDSS [Angehrn 1991a] into a Conversational DSS.The objective of this project is to identify the generic architecture of a new type ofvisual interactive system in which electronic agents encapsulating MCDMmethods and Case-Based Reasoning techniques [Riesbeck and Schank 1989]stimulate the user(s) along the whole decision-making process.
The design of Decision-Making Arenas is the second main research directionrelated to the Conversational Framework. The majority of today's DSS do notprovide such a "flexible space" in which conversation, and hence reflectivelearning can take place. One of the main reasons is that the identification of sucha level of human-computer interaction is still a complex design task. Thecomplexity of this task can be expressed in terms of bridging four "Gulfs", asillustrated in Figure 5. The first two Gulfs concern the interaction processbetween the user and the DMA. The difficulty faced here can be referred back to adiscrepancy between psychological variables (the terms in which a decision-maker expresses his or her goals) and physical variables (the terms in which themechanisms and states of a computer-based system are expressed) [Norman 1986].Hutchins, Hollan and Norman [1986] first described this discrepancy using themetaphor of Gulfs representing the distances between a person's goals andknowledge and the level of description provided by the system.
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Gulf of Gulf ofIntervention Execution
stimulus agents DM Arena
Dynamic AnalysisGulf of
Evaluation
decision maker
Besides these two first Gulfs (for a discussion of the Gulfs of Evaluation andExecution, see Hutchins et al. [1986]) which divide the decision-maker from thephysical environment of the DMA, the designer of a Conversational DSS has tobridge two further Gulfs dividing the DMA from the Stimulus Agents. It is theneed to bridge these two pairs of Gulfs at the same time which makes the designof suitable arenas a particularly complex and challenging task. On the one hand,the type of representations and the language used to map problems and solutionalternatives into the arena must fit the goals and knowledge of the DSS users (inorder to justify the use of the arena as a catalyst for reflective learning). On theother hand, the content of the DMA must be structured enough to enableStimulus Agents to dynamically analyze it and subsequently intervene byproviding additional information, suggestions or criticism.
Figure 5: Four Gulfs involved in the design of DM Arenas.
As a result, research related to the design of DMAs falls into the domaindenominated "cognitive engineering" [Norman 1986] which combines Human-Computer Interaction studies (cf. for instance the concept of "interface as drama"proposed by Laurel [1986]) with research on "modeling processes" and"representation schemes" initiated in the fields of Artificial Intelligence [Bobrowand Collins 1975; Brodie et al. 1984] and Operations Research [Geoffrion 1987,1989]. In current DSS, the role of the DMA is often indirectly assumed by a flexiblemodeling environment supporting the user in describing and exploring decisionproblem using multiple representations and levels of abstraction. Two recentexamples of such environments are reported by Piela and McKalvey [1992] andAngehrn and Liithi [1990]. Both papers describe flexible and functionally richinteractive modeling environments based on an object-oriented knowledgerepresentation scheme [Stefik and Bobrow 1983] and a direct manipulationinterface [Schneiderman 1983]. In addition, the DSS generator described inAngehrn and Liithi [1990] illustrates a first attempt to implement a model-basedStimulus Agent interacting with the user through an exchange of "examples".Besides providing direct access to a variety of combinatorial optimizationmethods, this agent is able to analyze the problems and examples of solutionalternatives modeled by the user, to suggest specific methods to be employed in aspecific context, and to generate and display new solutions [Angehrn 1991b].
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ConclusionsThe objective of this paper was to present and discuss an alternative frameworkfor computer-aided decision making based on the two key concepts of Decision-Making Arenas and Stimulus Agents. Besides reflecting and integrating recentresearch efforts in the DSS field, the Conversational Framework provides analternative way to solve the "guidance vs. flexibility" dilemma traditional DSSare typically faced with, as well as a promising approach to enhance creativity inhuman-computer problem solving. Although based on a different interpretationof how "support" should be provided to human decision-makers (team-workand reflective learning vs access to problem solving techniques), DSS based onthe Conversational Framework have been shown to represent an extension andgeneralization of current DSS types.
Given the complexity of designing and implementing suitable Decision-MakingArenas and Stimulus Agents, the realization of Conversational DSS requiresefforts which go beyond the research projects currently in progress which werementioned in the last section. In particular, the Conversational Framework cancontribute to the development of standards in the DSS field (structured modelrepresentation standards enabling the independent development of agents andtheir flexible connection to a given DMA, standard protocols used to track theevents taking place in a DMA, etc.). As a further contribution, the ConversationalFramework indicates concrete directions for establishing or strengtheninginterdisciplinary links between the DSS research domain and other scientificfields encompassing studies on group dynamics, collaboration science,(computer-aided) learning and cognitive psychology. In more general terms, themain benefit might result from providing an alternative vision to both DSSresearchers and users.
AcknowledgementThe research on which this paper is based has been supported by the Research &Development Department of the European Institute of Business Administration.
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Silver, M.S., "Decision Support Systems: Directed and Nondirected Change,"Information Systems Research, 1, 1, 1990, 47-70.
Elam, J.J. and M. Mead, "Can Software Influence Creativity?" InformationSystems Research, 1, 1, 1990, 1-22.
Angehrn, A.A., "Supporting Multicriteria Decision Making: New Perspectivesand New Systems," Proc. of the First ISDSS Conference, Austin, Texas, 1990,521-535; INSEAD Working Paper No. 91/36/TM.
Newell, A. and H.A. Simon, Human Problem Solving, Prentice Hall, New Jersey,1972.
Dery, D., "Decision-making, Problem-solving and Organizational Learning,"Omega, 11, 4, 1983, 321-328.
ISDSS, Proceedings of the First ISDSS (International Society of DSS) Conference,Austin, Texas, 1990.
Jakob, V.S., R. Pakath and J.S. Zaveri, "Adaptive Decision Support Systems:Incorporating Learning into Decision Support Systems," Proc. of the FirstISDSS Conference, Austin, Texas, 1990, 313-330;
Churchman, C.W., The Design of Inquiring Systems: Basic Concepts of Systemsand Organization, Basic Books, New York, London, 1971.
Fitter, M.J. and M.E. Sime, "Responsibility and Shared Decision Making," inSmith, H.T. and T.R.G. Green (eds.), Human Interaction with Computers,Academic Press, 1980.
Boxer, P.J., "Supporting Reflective Learning: Towards a Reflexive Theory ofForm," Human Relations, 33, 1, 1980, 1-22.
Evans, J.S.B.T., Bias in Human Reasoning: Causes and Consequences, LawrenceErlbatun Ass., Hillsdale, NJ, 1989.
Hogarth, R.M., Judgment and Choice. The Psychology of Decision, John Wiley &Sons, 1987.
Nii, P., "The Blackboard Model of Problem Solving: Part 1 and 2," Al Magazine, 7,2 and 3, 1986, 38-53 and 82-106.
Winograd, T. and F. Flores, Understanding Computers and Cognition: A NewFoundation for Design, Ablex, 1986.
Zeleny, M., "Cognitive Equilibrium: A New Paradigm of Decision Making?"Human Systems Management, 8, 1989, 185-188.
Zachary, W., "A Cognitively Based Functional Taxonomy of Decision SupportTechniques," Human-Computer Interaction, 2, 1, 1986, 25-63.
-16-
Te'eni, D. and M.J. Ginzberg, "Human-computer Decision Systems: The MultipleRoles of DSS," _European Journal of Operational Research, 50, 1991, 127-139.
Manheim, M.L., "An Architecture for Active DSS," Proc. of the 21st AnnualHawaii International Conference on System Sciences, 1988, 356-365.
Mili, F., "Active DSS: Issues and Challenges," Paper presented at the TIMS/ORSAJoint National Meeting, Las Vegas, May 7-9, 1990.
Raghavan, S.A. and D.R. Chang, "Exploring Active Decision Support: The JanusProject," Proc. of the 22nd Annual Hawaii International Conference onSystem Sciences, 1989, 33-45.
Raghavan, S.A., "Birbal: A Computer-based Devil's Advocate," Proc. of the 23rdAnnual Hawaii International Conference on System Sciences, 1990, 383-390.
Cohen, P.R. and E.A. Feigenbaum (eds.), The Handbook of Artificial Intelligence,Vol. 3, Kaufmann, Los Altos, CA, 1982.
Fischer, G. and T. Mastaglio, "Computer-based Critics," Proc. of the 22nd AnnualHawaii International Conference on System Sciences, 1989, 427-436.
Thomas, L.F., "Demon and Double-Demon: Computer-aided Conversation withYourself," Centre for the Study of Human Learning, Brunel University,Uxbridge, England.
Angehrn, A.A., "Designing Humanized Systems for Multiple Criteria DecisionMaking," Human Systems Management, 10, 3, 1991a, 221-232.
Riesbeck, C.K. and R.C. Shank, Inside Case-Based Reasoning, Lawrence ErlbaumAss., Hillsdale, NJ, 1989.
Norman, D.A., "Cognitive Engineering," in Norman, D.A. and S.W. Draper (eds.),User Centered System Design: New Perspectives on Human-ComputerInteraction, Lawrence Erlbaum Ass., Hillsdale, NJ,1986, 31-61.
Hutchins, E.L., J.D. Hollan and D.A. Norman, "Direct Manipulation Interfaces,"in Norman, D.A. and S.W. Draper (eds.), User Centered System Design: NewPerspectives on Human-Computer Interaction, Lawrence ErlbaumAssociates Ltd, Hillsdale NJ, 1986, 87-124.
Laurel, B.K., "Interface as Mimesis," in Norman, D.A. and S.W. Draper (eds.),User Centered System Design: New Perspectives on Human-ComputerInteraction, Lawrence Erlbaum Associates Ltd, Hillsdale NJ, 1986, 67-85.
Bobrow, D.G. and A. Collins (eds.), Representation and Understanding, AcademicPress, New York, 1975.
Brodie, M.L., J. Mylopoulos and J.W. Schmidt (eds.), On Conceptual Modelling,Springer-Verlag, New York, 1984.
Geoffrion, A.M., "Computer-based Modeling Environments," European Journalof Operational Research, 41, 1989, 33-43.
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Geoffrion, A.M., "Introduction to Structured Modeling," Management Science,33, 5, 1987, 574-588.
Piela, P. and R. McKelvey, "An Introduction to ASCEND: Its Language andInteractive Environment," to appear in: Proc. of the 25th Annual HawaiiInternational Conference on System Sciences, 1992.
Shneiderman, B., "Direct Manipulation: A step beyond ProgrammingLanguages," IEEE Computer, 16, 8, 1983, 57-69.
Stefik, M. and D.G. Bobrow, "Object-oriented Programming: Themes andVariations," Al Magazine, 6, 4, 1986, 40-62.
Angehrn, A.A., "Modeling by Example: A Link between Users, Models andMethods in DSS," European Journal of Operational Research, 55, 1991b.
- 18 -
1988
88/01 "Factors affecting judgemental forecasts and
confidence intervals", January 1988.
Michael LAWRENCE and
Spyms MAKRIDAKIS
88/02
88/03
88/04
Spyros MAKRIDAKIS
James TEBOUL
Susan SCHNEIDER
"Predicting recessions and other turning
points", January 19814.
"De-industrialize service for quality", January
1988.
"National vs. corporate culture: implications
for human resource management", January
1988.
88/05 "Tbe swinging dollar: is Europe out of
step?", January 1988.
Charles WYPLOSZ
88/06 "Let Melts dans les canaux de
distribution", January 1988.
Reinhard ANGELMAR
"Competitive advantage: a resource based
perspective", January 1988.
88/07 Ingemar DIERICKX
and Karel COOL
Reinhard ANGELMAR
and Susan SCHNEIDER
"Issues in the study of organizational
cognition", February 1988.
88/08
"Price formation and product design through
bidding", February 1988.
88/09 Bernard SINCLAIR-
DESGAGNE`
"The robustness of some standard auction
game forms", February 1988.
88/10 Bernard SINCLAIR-
DESGAGNE
"When stationary strategies are equilibrium
bidding strategy: The single-crossing
property", February 1988.
Bernard SINCLAIR-
DESGAGNE
8R/12 Spyros MAKRIDAKIS "Business firms and managers in the 21st
century", February 1988
RR/13 Manfred KETS DE VRIES "Alexithymia in organizational life: the
organization man revisited", February 1988.
88/14 Alain NOEL "The interpretation of strategies: a study ofthe impact of CEOs on the
corporation", March 1988.
RR/15 Anil DEOLALIKAR and "The production of and returns from
Lars-Hendrik ROLLER industrial innovation: an econometric
analysis for • developing country", December
1987.
RR/16 Gabriel HAWAWINI "Market efficiency and equity pricing:
international evidence and implications for
global investing", March 1988.
81/17 Michael BURDA "Monopolistic competition, costs ofadjustment and the behavior of European
employment", September 1987.
88/18 Michael BURDA "Reflections on "Wait Unemployment" in
Europe", November 1987, revised February
1988.
RR/19 M.J. LAWRENCE and "Individual bias in judgements ofSpyros MAKRIDAKIS confidence", March 1988.
88/20 Jean DERM1NE,
Damien NEVEN and
"Portfolio selection by mutual funds, an
equilibrium model", March 1988.
J.F. THISSE
88/21 James TEBOUL "De-industrialize service for quality", March
1988 (88/03 Revised).
88/22 Lars-Hendrik ROLLER "Proper Quadratic Functions with anApplication to AT&T", May 1987 (Revised
March 1988).
1NSF,AD WORKING PAPERS SERIES
88/24
B. Espen ECKBO and
"Information disclosure, means of payment,
Herwig LANGOHR and takeover premia. Public and Private
tender offers in France", July 1985, Sixth
revision, April 1988.
88/25
Everette S. GARDNER
"The future of forecasting", April 1988.
and Spyros MAKRIDAKIS
88/26
Sjur Didrik FLAM
"Semi-competitive Cournot equilibrium in
and Georges .ZACCOUR multistage oligopolies", April 1988.
88/27
Murugappa KRISHNAN
"Entry game with resalable capacity",
Lars-Hendrik ROLLER
April 1988.
Sumantra GHOSHAL and
C. A. BARTLETT
Naresh K. MALHOTRA,
Christian PINSON and
Arun K. JAIN
"The multinational corporation as a network:
perspectives from interorganizational
theory", May 1988.
"Consumer cognitive complexity and the
dimensionality of multidimensional scaling
configurations", May 1988.
88/28
88/29
88/30
Catherine C. ECKEL
"The financial fallout from Chernobyl: risk
and Theo VERMAELEN
perceptions and regulatory response", May
1988.
88/31
Sumantra GHOSHAL and
"Creation, adoption, and diffusion of
Christopher BARTLETT
innovations by subsidiaries of multinational
corporations", June 1988.
88/32
}Ceara FERDOWS and
"International manufacturing: positioning
David SACKR1DER plants for success", June 1988.
88/33
Mihkel M. TOMBAK
"The importance of flexibility in
manufacturing", June 1988.
88/34 Mihkel M. TOMBAK "Flexibility: an important dimension inmanufacturing", June 1988.
88/35 Mihkel M. TOMBAK "A strategic analysis of investment in flexiblemanufacturing systems", July 1988.
88/36 Vikaa TIBREWALA and "A Predictive Test of the NBD Model thatBruce BUCHANAN Controls for Non-stationarity", June 1988.
/37 Murugappa KRISHNAN "Regulating Price-Liability Competition ToLars-Hendrik ROLLER Improve Welfare", July 1988.
88/38 Manfred KETS DE VRIES "The Motivating Role of Envy : A ForgottenFactor in Management", April 88.
88/39 Manfred KETS DE VRIES "The Leader as Mirror : ClinicalReflections", July 1988.
88/40 Josef LAKONISHOK and "Anomalous price behavior aroundTheo VERMAELEN repurchase tender offers", August 1988.
88/41 Charles WYPLOSZ "Assymetry in the EMS: intentional orsystemic?", August 1988.
88/42 Paul EVANS "Organizational development in thetransnational enterprise", June 1988.
88/43 B. SINCLAIR-DESGAGNE "Group decision support systems implementBayesian rationality", September 1988.
88/44 Einem MAHMOUD and "The state of the art and future directionsSpyros MAICRIDAKIS in combining forecasts", September 1988.
88/45 Robert KORAJCZYK "An empirical investigation of internationaland Claude VIALLEr asset pricing", November 1986, revised
August 1988.
88/46 Yves DOZ and "Front intent to outcome: a processAmy SHUEN framework for partnerships", August 1988.
88/47 Alain BULTEZ,
Els GUSBRECHTS,
"Asymmetric cannibalism between substituteitems listed by retailers*, September 1988.
88/23 Sjur Didrik FLAM
"Equilibres de Nash-Cournot dans le marche
and Georges ZACCOUR europ&en du gaz: un cas oh les solutions en
boucle ouverte et en feedback coincident",
Mars 1988.
88/58 B. SINCLAIR-DESGAGNEand Mihkel M. TOMBAK
"Reflections on 'Wait unemployment' inEurope, II", April 1988 revised September1988.
"Information asymmetry and equity issues",September 1988.
"Managing expert systems: from inceptionthrough updating", October 1987.
"Technology, work, and the organization:the impact of expert systems", July 1988.
"Cognition and organizational analysis:who's minding the store?", September 1988.
"Whatever happened to the philosopher-king: the leader's addiction to power,September 1988.
"Strategic choice of flexible productiontechnologies and welfare implications",October 1988
"Method of moments tests of contingentclaims asset pricing models", October 1988.
"Size-sorted portfolios and the violation ofthe random walk hypothesis: Additionalempirical evidence and implication for testsof asset pricing models", June 1988
"Data transferability: estimating the responseeffect of future events based on historicalanalogy", October 1988.
"Assessing economic inequality", November1988.
88/59 Martin KILDUFF
88/60 Michael BURDA
88/61 Lars-Hendrik ROLLER
88/62 Cynthia VAN HULLE,Theo VERMAELEN andPaul DE WOUTERS
88/63 Fernando NASCIMENTOand Wilfried R.VANHONACKER
88/64 Kasra FERDOWS
88/65 Amoud DE MEYERand Kasra FERDOWS
88/66 Nathalie D1ERKENS
88/67
Paul S. ADLER andKasra FERDOWS
1989
89/01
Joyce K. BYRER andTawfik JELASSI
89/02 Louis A. LE BLANCand Tawfik JELASSI
"The interpersonal stricture of decisionmaking: • social comparison approach toorganizational choice", November 1988.
"D mismatch really the problem? Someestimates of the Cheiwood Gate II model
with US data", September 1988.
"Modelling cost structure: the Bell Systemrevisited", November 1988.
"Regulation, taxes and the market forcorporate control in Belgium", September1988.
"Strategic pricing of differentiated consumerdurables in a dynamic duopoly: a numerical
analysis", October 1988.
"Charting strategic roles for internationalfactories", December 1988.
"Quality up, technology down", October 1988
"A discussion of exact measures ofinformation assymetry: the example of Myersand MAN( model or the importance of the
asset structure of the firm", December 1988.
"The chief technology officer", December1988.
"The impact of language theories on DSS
dialog", January 1989.
"DSS software selection: • multiple criteriadecision methodology", January 1989.
Philippe NAERT andPiet VANDEN ABEELE
88/48
Michael BURDA
88/49
Nathalie DIERKENS
88/50
Rob WEITZ andAmoud DE MEYER
88/51
Rob WEITZ
88/52
Susan SCHNEIDER andReinhard ANGELMAR
88/53
Manfred KETS DE VRIES
88/54
Lars-Hendrik ROLLERand Mihkel M. TOMBAK
88/55
Peter BOSSAERTSand Pierre HILLION
88/56
Pierre HILLION
88/57
Wilfried VANHONACKERand Lydia PRICE
89/03 Beth H. JONES andTawfik JELASSI
89/04
Kasra FERDOWS and
Arnoud DE MEYER
89/05 Martin KILDUFF and
Reinhard ANGELMAR
89/06
Mihkel M. TOMBAK and
B. SINCLAIR-DESGAGNE
89/07 Damien 1. NEVEN
89/08 Arnoud DE MEYER and
Hellmut SCHOTTE
89/09
Damien NEVEN,
Carmen MATUTES and
Marcel CORSTJENS
89/10 Nathalie DIERKENS,
Bruno GERARD and
Pierre HILLION
89/11
Manfred KETS DE VRIES
and Alain NOEL
89/12
Wilfried VANHONACKER
"Negotiation support: the effects of computerintervention and conflict level on bargainingoutcome", January 1989.
"Lasting improvement in manufacturingperformance: In search of a new theory",January 1989.
"Shared history or shared culture? Theeffects of time, culture, and performance oninstitutionalization in simulatedorganizations", January 1989.
"Coordinating manufacturing and businessstrategies: I", February 1989.
"Structural adjustment in European retailhankie's. Some view from industrialorganisation", January 1989.
"Trends in the development of technologyand their effects on the production structurein the European Community", January 1989.
"Brand proliferation and entry deterrence",February 1989.
"A market based approach to the valuationof the assets in place and the growthopportunities of the firm", December 1988.
"Understanding the leader-strategy interface:application of the strategic relationshipinterview method", February 1989.
"Estimating dynamic response models whewthe data are subject to different temporalaggregation", January 1989.
89/13 Manfred KETS DE VRIES
89/14 Reinhard ANGELMAR
89/15 Reinhard ANGELMAR
89/16
Wilfried VANHONACKER,
Donald LEHMANN and
Fareena SULTAN
89/17 Gilles AMADO,
Claude FAUCHEUX and
Andre LAURENT
89/18
Srinivasan BALAK-
RISHNAN and
Mitchell KOZA
89/19
Wilfried VANHONACKER,
Donald LEHMANN and
Fareena SULTAN
89/20
Wilfried VANHONACKER
and Russell WINER
89/21 Arnoud de MEYER and
Kasra FERDOWS
89/22 Manfred KETS DE VRIES
and Sydney PERZOW
89/23
Robert KORAJCZYK and
Claude VIALLET
89/24 Martin KILDUFF and
Mitchel ABOLAFIA
"The impostor syndrome: a disquietingphenonienon in organizational life", February
1989.
"Product innovation: a tool for competitiveadvantage", March 1989.
"Evaluating a firm's product innovationperformance", March 1989.
"Combining related and sparse data in linearregression models", February 1989.
"Changeseent organisationnel et rttalit4sculturelles: contrastes franco-americains",March 1989.
"Information asymmetry, market failure andjoint-ventures: theory and evidence",March 1989.
"Combining related and sparse data in linearregression models", Revised March 1989.
"A rational random behavior model ofchoice", Revised March 1989.
"Influence of manufacturing improvementprogrammes on performance", April 1989.
"What is the role of character inpsychoanalysis?" April 1989.
"Equity risk premia and the pricing offoreign exchange risk" April 1989.
"The social destruction of reality:Organisational conflict as social drama"zApril 1989.
89/25 Roger BETANCOURT and
David GAUTSCHI
89126
Charles BEAN,
Edmond MALINVAUD,
Peter BERNHOLZ,
Francesco GIAVAllI
and Charles WYPLOSZ
89/27
David KRACKHARDT and
Martin KILDUFF
89/28
Martin KILDUFF
89/29 Robert GOGEL and
Jean-Claude LARRECHE
89/30 Lars-Hendrik ROLLER
and Mihkel M. TOMBAK
89/31 Michael C. BURDA and
Stefan GERLACH
89132 Peter HAUG and
Tawfik JELASSI
89/33 Bernard SINCLAIR-
DESGAGNE
89/34 Sumantra GHOSHAL and
Nittin NOHRIA
89/35
Jean DERMINE and
Pierre HILLION
"Two essential characteristics of retailmarkets and their economic consequences"
March 1989.
"Macroeconomic policies for 1992: the
transition and after", April 1989.
"Friendship patterns and culturalattributions: the control of organisational
diversity", April 1989.
"The interpersonal structure of decision
making: a social comparison approach toorganizational choke", Revised April 1989.
"The battlefield for 1992: product strengthand geographic coverage", May 1989.
"Competition and Investment in FlexibleTechnologies", May 1989.
"Intertemporal prices and the US tradebalance in durable goods", July 1989.
"Application and evaluation of a multi-criteria decision support system for thedynamic selection of U.S. manufacturinglocations', May 1989.
"Design flexibility in monopsonisticindustries", May 1989.
"Requisite variety versus shared values:managing corporate-division relationships inthe M-Form organisation", May 1989.
"Deposit rate ceilings and the market valueof banks: The case of France 1971-1981",May 1989.
89/36 Martin KILDUFF
89/37
Manfred KETS DE VRIES
89/38
Manfred KETS DE VRIES
89/39
Robert KORAJCZYK and
Claude VIALLET
89/40
Balaji CHAKRAVARTHY
89/41 B. SINCLAIR-DESGAGNE
and Nathalie DIERKENS
89/42
Robert ANSON and
Tawfik JELASSI
89/43 Michael BURDA
89/44 Balaji CHAKRAVARTHY
and Peter LORANGE
89/45
Rob WEITZ and
Arnoud DE MEYER
89/46
Marcel CORSTJENS,
Carmen MATUTES and
Damien NEVEN
89/47 Manfred KETS DE VRIES
and Christine MEAD
89/48 Damien NEVEN andLars-Hendrik ROLLER
"A dispositional approach to social networks:the case of organizational choice", May 1989.
"The organisational fool: balancing aleader's hubris", May 1989.
"The CEO blues", June 1989.
"An empirical investigation of internationalasset pricing", (Revised June 1989).
"Management systems for innovation andproductivity", June 1989.
"The strategic supply of precisions", June
1989.
"A development framework for computer-supported conflict resobton", July 1989.
"A note on ruing costs sod severance benefitsin equilibrium unemployment", June 1989.
"Strategic adaptation in multi-businessfirms", June 1989.
"Managing expert systems: a framework andcase study", lune 1989.
"Entry Encouragement", July 1989.
"The global dimension in leadership andorganization: issues and controversies", April1989.
"European integration and trade flows",August 1989.
89/49 Jean DERMINE "Home country control and mutual
recognition", July 1989. 89/62 Arnoud DE MEYER
(TM)
89/50 Jean DERMINE "The specialization of financial institutions,
the EEC model", August 1989. 89/63 Enver YUCESAN end
(TM) Lee SCHRUBEN
89/51 Spyroa MAKRIDAKIS "Sliding simulation: a new approach to time
series forecasting", July 1989. 89/64 Enver YUCESAN and
(TM) Lee SCHRUBEN
89/52 Arnoud DE MEYER "Shortening development cycle times: a
manufacturer's perspective", August 1989. 89/65 Soumitra DUTTA and
89/53 Spyroa MAKRIDAJUS "Why combining works?", July 1989.
(TM,
AC, FIN)
Piero BONISSONE
89/54 S. BALAKRISHNAN "Organisation costs and a theory of joint 89/66 B. SINCLAIR-DESGAGNE
and Mitchell KOZA ventures", September 1989. (TM.EP)
89/55 H. SCHUTTE "Euro-Japanete cooperation in information 89/67 Peter BOSSAERTS and
technology", September 1989. (FIN) Pierre HILLION
89/56 Wilfried VANHONACKER
and Lydia PRICE
"On the practical usefulness of meta-analysis
results", September 1989.
1990
89/57 Taekwon KIM,
Lars-Hendrik ROLLER
and Mihkel TOMBAK
"Market growth and the diffusion of
multiproduct technologies", September 1989. 90/01
TM/EP/AC
B. SINCLAIR-DESGAGNE
89/58 Lars-Hendrik ROLLER "Strategic aspects of flexible production 90/02 Michael BURDA
(EP,TM) and Mihkel TOMBAK technologies", October 1989. EP
89/59
(OH)
Manfred KETS DE VRIES,
Daphna ZEVADI,
Alain NOEL and
"Locus of control and entrepreneurship: a
three-country comparative study", October
1989.
90/03
TM
Arnaud DE MEYER
Mihkel TOMBAK
89/60 Enver YUCESAN and "Simulation graphs for design and analysis of 90/04 Gabriel HAWAWINI and
(TM) Lee SCHRUBEN discrete event simulation models", October FIN/EP Eric RAJENDRA
1989.
89/61 Susan SCHNEIDER and "Interpreting and responding to strategic 90/05 Gabriel HAWAWINI and
(AB) Armed DE MEYER issues: The impact of national culture",
October 1989.
FIN/EP Bertrand JACQUILLAT
"Technology strategy and international R&D
operations", October 1989.
"Equivalence of simulations: A graph
approach", November 1989.
"Complexity of simulation models: A graph
theoretic approach", November 1989.
"MARS: A mergers and acquisitions
reasoning system", November 1989.
"On the regulation of procurement bids",
November 1989.
"Market microstructure effects of
government intervention in the foreign
exchange market", December 1989.
"Unavoidable Mechanisms", January 1990.
"Monopolistic Competition, Costs ofAdjustment, and the Behaviour of EuropeanManufacturing Employment", January 1990.
"Management of Communication inInternational Research and Development",January 1990.
"The Transformadon of the EuropeanFinancial Services Industry: FromFragmentation to Integration", January 1990.
"European Equity Markets: Toward 1992
and Beyond", January 1990.
90/06 Gabriel HAWAWINI and "Integration of European Equity Markets:FIN/EP Eric RAJENDRA Implications of Structural Change for Key
Market Participants to and Beyond 1992",January 1990.
90/17
FIN
Nathalie DIERKENS "Information Asymmetry and Equity Issues",Revised January 1990.
90/18 Wilfried VANHONACKER "Managerial Decision Rules and the90/07 Gabriel HAWAWINI "Stock Market Anomalies and the Pricing of MKT Estimation of Dynamic Sales ResponseFIN/EP Equity on the Tokyo Stock Exchange",
January 1990.
Models", Revised January 1990.
90/19 Beth JONES and "The Effect of Computer Intervention and90/08TM/EP
Tawfik JELASSI and
B. SINCLAIR-DESGAGNE
"Modelling with MCDSS: What aboutEthics?", January 1990.
TM Tawfik JELASSI Task Structure on Bargaining Outcome",February 1990.
90/09 Alberto GIOVANNINI "Capital Controls and International Trade 90/20 Tawfik JELASSI, "An Introduction to Group Decision andEP/FIN and Jae WON PARK Finance", January 1990. TM Gregory KERSTEN and Negotiation Support", February 1990.
Stanley ZIONTS
90/10 Joyce BRYER and "The Impact of Language Theories on DSSTM Tawfik JELASSI Dialog", January 1990. 90/21 Roy SMITH and "Reconfiguration of the Global Securities
FIN Ingo WALTER Industry in the 1990's", February 1990.
90/11 Enver YUCESAN "An Overview of Frequency DomainTM Methodology for Simulation Sensitivity 90/22 Ingo WALTER "European Financial Integration and Its
Analysis", January 1990. FIN Implications for the United States", February
1990.90/12 Michael BURDA "Structural Change. Unemployment BenefitsEP and High Unemployment: A U.S.-European 90/23 Damien NEVEN "EEC Integration towards 1992: Some
Comparison", January 1990. EP/SM Distributional Aspects", Reviled December
1989
90/13 Soumitra DUTTA and "Approximate Reasoning about TemporalTM Shashi SHEKHAR Constraints in Real Time Planning and 90/24 Lars Tyge NIELSEN "Positive Prices in CAPM", January 1990.
Search", January 1990. FIN/EP
90/14
TM
Albert ANGEHRN and
Hans-Jakob LOTH!
"Visual Interactive Modelling and IntelligentDSS: Putting Theory Into Practice", January
90/25FIN/EP
Lars Tyge NIELSEN "Existence of Emulibrium in CAPM",January 1990.
1990.90/26 Charles KADUSHIN and "Why networking Fads: Double Binds and
90/15
TM
Arnoud DE MEYER,
Dirk DESCHOOLMEESTER,
Rudy MOENAERT and
"The Internal Technological Renewal of aBusiness Unit with a Mature Technology",January 1990.
OB/BP Michael BRIMM the Limitations of Shadow Networks",February 1990.
Jan BARBE 90/27 Abbas FOROUGHI and "NSS Solutions to Major NegotiationTM Tawfik JELASSI Stumbling Blocks", February 1990.
90/16 Richard LEVICH and "Tax-Driven Regulatory Drag: EuropeanFIN Ingo WALTER Financial Centers in the 1990's", January 90/28 Arnoud DE MEYER "The Manufacturing Contribution to
1990. TM Innovation", February 1990.
90/40 Manfred KETS DE VRIES "Leaders on the Couch: The case of Roberto90/29 Nathalie DIERKENS "A Discussion of Correct Measures of Oil Calvi", April 1990.FIN/AC Information Asymmetry", January 1990.
90/30 Lars Tyge NIELSEN "The Expected Utility of Portfolios of90/41FIN/EP
Gabriel HAWAWINI,
Itzhak SWARY and
"Capital Market Reaction to theAnnouncement of Interstate Banking
FIN/EP Assets", March 1990. 1k HWAN JANG Legislation", March 1990.
90/31 David GAUTSCHI and "What Determines U.S. Retail Margins?", 90/42 Joel STECKEL and "Cross-Validating Regression Models inMKT/EP Roger BETANCOURT February 1990. MKT Wilfried VANHONACKER Marketing Research", (Revised April 1990).
90/32 Srinivasan BALAK- "Information Asymmetry, Adverse Selection 90/43 Robert KORAJCZYK and "Equity Risk Premia and the Pricing ofSM RISHNAN and
Mitchell KOZAand Joint-Ventures: Theory and Evidence",Revised, January 1990.
•IN Claude VIALLET Foreign Exchange Risk", May 1990.
90/33 Caren SIEHL, "The Role of Rites of Integration in Service 90/44 Gilles AMADO, "Organisational Change and Cultural011 David BOWEN and Delivery", March 1990. 013 Claude FAUCHEUX and Realities: Franco-American Contrasts", April
Christine PEARSON Andre LAURENT 1990.
90/45 Soumitra DUTTA and "Integrating Case Based and Rule Based90/34FIN/EP
Jean DERMINE "The Gains from European BankingIntegration, a Call for a Pro-Active
TM Piero BONISSONE Reasoning: The Possibilistic Connection",May 1990.
Competition Policy", April 1990.90/46 Spyros MAKRIDAKIS "Exponential Smooth*: The Effect of
90/35 Jae Won PARK "Changing Uncertain() the Time- TM and Michele HIBON Initial Values and Loss Fluktions on Post-EP Varying Risk Premia in the Term Structure
of Nominal Interest Rates", December 1988,
Revised March 1990. 90/47 Lydia PRICE and
Sample Forecasting Accuracy".
"Improper Sampling in NaturalMKT Wilfried VANHONACKER Experiments: Limitations on the Use of
90/36 Arnoud DE MEYER "An Empirical Investigation of Meta-Analysis Results in BayesianTM Manufacturing Strategies in European Updating", Revised May 1990.
Industry", April 1990.90/48 Jae WON PARK "The Information in the Term Structure of
90/37TM/OB/SM
William CATS-BAR1L "Executive Information Systems: Developingan Approach to Open the Possibles", April
EP Interest Rates: Out-of-Sample ForecastingPerformance", June 1990.
1990.
90/49 Soumitra DUTTA "Approximate Reasoning by Analogy to90/38 Wilfried VANHONACKER "Managerial Decision Behaviour and the TM Answer Null Queries", June 1990.MKT Estimation of Dynamic Sales Response
Models", (Revised February 1990). 90/50 Daniel COHEN and "Price and Trade Effects of Exchange RatesEP Charles WYPLOSZ Fluctuations and the Design of Policy
90/39TM
Louis LE BLANC andTanfik JELASSI
"An Evaluation and Selection Methodologyfor Expert System Shells", May 1990.
Coordination", April 1990.
90/51 Michael BURDA and "Gross Labour Market Flows in Europe: 90/63 Sumantra GHOSHAL and "Organising Competitor Analysis Systems",EP Charles WYPLOSZ Some Stylized Facts", June 1990. SM Eleanor WESTNEY August 1990
90/52 Lars Tyge NIELSEN "The Utility of Infinite Menus", June 1990. 90/64 Sumantra GHOSHAL "Internal Differentiation and CorporateFIN SM Performance: Case of the Multinational
Corporation", August 199090/53 Michael Burda "The Consequences of German EconomicEP and Monetary Union", June 1990. 90/65 Charles WYPLOSZ "A Note on the Real Exchange Rate Effect of
El German Unification", August 199090/54 Damien NEVEN and "European Financial Regulation: AEl' Colin MEYER Framework for Policy Analysis", (Revised 90/66 Soumitra DUTTA and "Computer Support for Strategic and Tactical
May 1990). TM/SE/FIN Piero BONISSONE Planning in Mergers and Acquisitions",September 1990
90/55 Michael BURDA and "Intertemporal Prices and the US Trade
90/56
Stefan GERLACH
Damien NEVEN and
Balance", (Revised July 1990).
"The Structure and Determinants of East-West
90/67
TM/SE/FIN
Soumitra DUTTA and
Piero BONISSONE
"Integrating Prior Cases and Expert Knowledge Ina Mergers and Acquisitions Reasoning System",September 1990
Lars-Hendrik ROLLER Trade: A Preliminary Analysis of theManufacturing Sector", July 1990 90/68 Soumitra DUTTA "A Framework and Methodology for Enhancing the
TM/SE Rusin' ess Impact of Artificial Intelligence90/57 Lan Tyge NIELSEN Common Knowledge of a Multivariate Aggregate Applications", September 1990
FIN/EP/ Statistic", July 1990
TM 90/69 Soumitra DUTTA "A Model for Temporal Reasoning in MedicalTM Expert Systems", September 1990
90/58 Lars Tyge NIELSEN "Common Knowledge of Price and Expected CostFIN/EP/TM in an Oligopolistic Market", August 1990 90/70
TMAlbert ANGEHRN "'Triple C': A Visual Interactive MCDSS",
September 1990
90/59 Jean DERMINE and "Economies of Scale andFIN Lars-Hendrik ROLLER Scope in the French Mutual Funds (SICAV) 90/71 Philip PARKER and "Competitive Effects in Diffusion Models: An
Industry", August 1990 MKT Hubert GATIGNON Empirical Analysis", September 1990
90/60 Peri 12 and "An Interactive Group Decision Aid for 90/72 Enver YUCESAN "Analysis of Marko. Chains Using SimulationTM Tawfik JELASSI Multiobjective Problems: An Empirical TM Graph Models", October 1990
Assessment", September 1990
90/61 Pankaj CHANDRA and "Models for the Evlauation of Manufacturing90/73TM
Arnoud DE MEYER andKasra FERDOWS
"Removing the Barriers in Manufacturing",October 1990
TM Mihkel TOMBAK Flexibility", August 1990
90/62 Damien NEVEN and "Public Policy Towards TV Broadcasting in the 90/74 Sumantra GHOSHAL and "Requisite Complexity: Organising Headquarters-Menno VAN DUK Netherlands", August 1990 SM Nitin NOHRIA Subsidiary Relations in MNCs", October 1990
90/75MKT
Roger BETANCOURT andDavid GAUTSCH1
Mae Outputs of Retail Activities: Concepts,Measureaseat and Evidence', October 1990
90/117FIN/EP
Ian Tyge NIELSEN •Faineant of Equilibrium in CAPM: FurtherResale, December 1990
90/76 Wilfried VANHONACKER •1111ma1eria Decision Behaviour and the Estiosatios 90/116 Susan C. SCHNEIDER and •Copitim is Organisational Analysis: Who'sMKT 1111 Dynamic Saes Respoase Models",
Revised October 1990011/MKT Reinhard ANGELMAR Mining the &ore?• Revised, December 1990
90/119 Manfred F.R. KETS DE VRIES MN CEO Ma Cesidn't Talk Straight awl Other90/77 Warned VANHONACKER 'Testae the Koyck Scheme of Sales Response le OB Tales Ryas as Board Rem,• December 1990MKT Advertising: Am Aparegatiom-ladeprodent
Aulecorrelatiom Tel •, October 1990 90/90 Philip PARKER • rice Bestitity Dynamics ever the AdoptionMKT 1.41147411: An F411Pilieal Study,* December 1990
90/71 Michael BURDA and •Encluatge RAW Dynamics sad CurrencyEr Stefan GERLACH Uoilication The Ostmark - DM Rate,
October 1990
90179 Anil GABA •Isferaces with am Unknown Noise Level is •TM Berms& Process•, October 1990
90/80 And GABA and *UMig Survey Data is loferesces about PurchaseTM Robert WINKLER Behaviour•, October 1990 1991
90/11 Tavfik JELASSI •De Paso* MI Foto= Baffin et Orieutatiorts desTM *awes laeractifs d'itide I Is Minas;
October 199091/01TM/SISI
Lug VAN WASSENHOVE,Leonard FORTUIN and
*Operational Itaseerch Cam Do Mere for ManagersMum They Iliad;
Paul VAN BEEK January 199190/82 Charles WYPLOSZ 'Monetary Wino sod Fiscal Policy Disciplime,•EP November 1990 91/02
TM/SINLa VAN WASSENHOVE,Leonard FORTUIN and
Naperetimal Research sad Eavinsaseemt,"January 1991
90/83uN/TM
Natalie DIBUCENS andBernard SINCLAIR-DESGAGNE
•Imformalios Asymmetry and CorporateComnummicatiore Results of a Pilot Study*,November 1990 91/03
Paul VAN BEEK
Paha HIETALA and •Am Implicit Dividend Increase is Rights Issues:FIN Tinto LOYTTYNIEMI Theory anal Evidence; January 1991
90/84 Philip M. PARKER *Me Effect of Advertising on Price and Quality:MKT The Optometric Industry Revisited,* 91/04 Lard Tyge NIELSEN *Two-Phad Separatism, Fatter Structure sad
December 1990 FIN Ralimbess,• January 1991
9045 Avijit GHOSH and •Optimal Twang sod Locales is Competitive 91/05 Susan SCHNEIDER 'Managing Bonadaries is Organisations;MKT Vikas TIBREWALA Markets; November 1990 OB lawny 1991
9046 Olivier CADOT and "Psalm* arid Success in Politics, November 1990 91/06 Manfred 10E1'S DE VRIES, *Undmitmarmeg the Loader-Strategy loterfare:EP/1M Bernard SINCLA1R-DESGAGNE OB Danny MILLER and Appficatiem a the Strategic Relatiemship Interview
Main NOEL Method,' January 1990 (89/11. revised April 1990)
91/07 Olivier CADOT "Lending to Insolvent Countries: A Paradoxical
El' Story," January 1991 91/19
MKT
Vikss TIBREWALA and "An Aggregate Test of Purchase Regularity",Bruce BUCHANAN March 1991
91/08 Charles WYPLOSZ "Post-Reform East and West: CapitalEP Accumulation and the Labour Mobility 91/20 Darius SABAVALA and "Monitoring Short-Run Changes in Purchasing
Constraint," January 1991 MKT Vitas TIBREWALA Behaviour", March 1991
91/09 Spyros MAKRIDAKIS "What can we Learn from Failure?", February 1991 91/21 Sumantra GHOSHAL, "Intermit Communication within MNCs: TheTM SM Harry KORINE and Influence of Formal Structure Versus Integrative
Gabriel SZULANSKI Processes", April 1991
91/10 Luc Van WASSENHOVE and "Integrating Scheduling with Belching and
TM C. N. POTTS Lot-Sizing: A Review of Algorithms and 91/22 David GOOD, "EC Integration and the Structure of the Franco-
Complexity", February 1991 EP Lars-Hendrik ROLLER and American Airline Industries: Implications forRobin SICKLES Efficiency and Welfare", April 1991
91/11 Luc VAN WASSENHOVE et al. "Multi-Item Lotsizing in Capacitated Multi-Stage
TM Serial Systems", February 1991 91/23 Spyros MAKRIDAKIS and "Exponential Smoothing: The Effect of InitialTM Michele HIBON Values and Loss Functions on Post-Sample
91/12 Albert ANGEHRN "Interpretative Computer Intelligence: A Link Forecasting Accuracy", April 1991 (Revision of
TM between Users, Models and Methods in DSS",
February 1991
90/46)
91/24 Louis LE BLANC and "An Empirical Assessment of Choice Models for
91/13EP
Michael BURDA "Labor and Product Markets in Czechoslovakia and
the Ex-GDR: A Twin Study", February 1991
TM Tawfik JELASSI Software Evaluation and Selection", May 1991
91/25 Luk N. VAN WASSENHOVE and "Trade-Offs? What Trade-Offs?" April 1991
91/14 Roger BETANCOURT and "The Output of Retail Activities: French SM/TM Charles J. CORBE1T
MKT David GAUTSCHI Evidence", February 1991
91/26 Luk N. VAN WASSENHOVE and "Single Machine Scheduling to Minimize Total Late
91/15
OB
Manfred F.R. KETS DE VRIES "Exploding the Myth about Rational Organisations
and Executives", March 1991
TM C.N. POTTS Work", April 1991
91/27 Nathalie DIERKENS "A Discussion of Correct Measures of Information
91/16 Amoud DE MEYER and "Factories of the Future: Executive Summary of FIN Asymmetry: The Example of Myers and Malta's
TM Kura FERDOWS et.al. the 1990 International Manufacturing Futures
Survey", March 1991
Model or the Importance of the Asset Stricture ofthe Firm", May 1991
91/17 Dirk CATTRYSSE, "Heuristics for the Discrete Lotsizing and 91/28 Philip M. PARKER "A Note on: 'Advertising and the Price and Quality
TM Roelof KUIK,
Marc SALOMON and
Scheduling Problem with Setup Times", March 1991 MKT of Optometric Services', June 1991
Luk VAN WASSENHOVE 91/29 Tawfik JELASSI and "An Empirical Study'of an Interactive, Session-
TM Abbas FOROUGHI Oriented Computerised Negotiation Support System
91/18 C.N. POTTS and "Approximation Algorithms for Scheduling a Single (NSS)", June 1991
TM Luk VAN WASSENHOVE Machine to Minimize Total Late Work",
March 1991
91/30 Wilfricd R. VANHONACKER and "Using Meta-Analysis Results in Bayesian Updating:MKT Lydia J. PRICE The Empty Cell Problem". June 1991 91/43 Sumantra GHOSHAL and "Building Transnational Capabilities: The
SM Christopher BARTLETT Management Challenge", September 199191/31 Rezaul KABIR and "Insider Trading Restrictions and the StockFIN Theo VERMAELEN Market", June 1991 91/44 Sumantra GHOSHAL and "Distributed Innovation in the 'Differentiated
SM Nitin NOHRIA Network' Multinational", September 199191/32 Susan C. SCHNEIDER "Organisational Sensemaking: 1992", June 1991
OB 91/45 Philip M. PARKER "The Effect of Advertising on Price and Quality:MKT An Empirical Study of Eye Examinations, Sweet
91/33 Michael C. BURDA and "German Trade Unions after Unification - Third Lemons and Self-Deceivers", September 1991EP Michael FUNKE Degree Wage Discriminating Monopolists?",
June 1991 91/46 Philip M. PARKER "Pricing Strategies in Markets with DynamicMKT Elasticities", October 1991
91/34 Jean DERMINE "The BIS Proposal for the Measurement of InterestFIN Rate Risk, Some Pitfalls", June 1991 91/47 Philip M. PARKER "A Study of Price Elasticity Dynamics Using
MKT Parsimonious Replacement/Multiple Purchase91/35FIN
Jean DERMINE "The Regulation of Financial Services in the EC,Centralization or National Autonomy?" June 1991
Diffusion Models", October 1991
91/48 H. Landis GABEL and "Managerial Incentives and Environmental91/36 Albert ANGEHRN "Supporting Multicriteria Decision Making: New EP/TM Bernard SINCLAIR-DESGAGNE Compliance", October 1991TM Perspectives and New Systems", August 1991
91/49 Bernard SINCLAIR-DESGAGNE "The First-Order Approach to Multi-Task91/37 Ingo WALTER and "The Introduction of Universal Banking in Canada: TM Principal-Agent Problems", October 1991EP Hugh THOMAS An Event Study", August 1991
91/50 Luk VAN WASSENHOVE and "How Green is Your Manufacturing Strategy?"91/38 Ingo WALTER and "National and Global Competitiveness of New York SM/TM Charles CORBETT October 1991
EP Anthony SAUNDERS City as a Financial Center", August 1991
91/51 Philip M. PARKER "Choosing Among Diffusion Models: Some91/39EP
Ingo WALTER andAnthony SAUNDERS
"Reconfiguration of Banking and Capital Marketsin Eastern Europe", August 1991
MKT Empirical Guidelines", October 1991
91/52 Michael BURDA and "Human Capital, Investment and Migration in an91/40TM
Luk VAN WASSENHOVE,Dirk CATTRYSSE and
"A Set Partitioning Heuristic for the GeneralizedAssignment Problem", August 1991
EP Charles WYPLOSZ Integrated Europe", October 1991
Marc SALOMON 91/53 Michael BURDA and "Labour Mobility and German Integration: SomeEP Charles WYPLOSZ Vignettes", October 1991
91/41TM
Luk VAN WASSENHOVE,M .Y. KOVALYOU and
"A Fully Polynomial Approximation Scheme forScheduling a Single Machine to Minimize Total
C.N. POTTS Weighted Late Work". August 1991
91/42 Rob R. WEITZ and "Solving A Multi-Criteria Allocation Problem:TM Tawfik JELASSI A Decision Support System Approach",
August 1991
