HD28 Oewey .M414 no. •iST. IS^b- SEP •85- 24 m. 1985 ^^ \ Center for Information Systems Research Massachusetts Institute of Technology Sloan School of Management Massachusetts Avenue n Cambridge, Massachusetts, 02139 ' SUPPORTING SENIOR EXECUTIVES' MODELS FOR PLANNING AND CONTROL Michael E. / Treacy June 1985 CISR WP #125 Sloan WP #1675-85 (c) Michael E. Treacy 1985 Center for Information Systems Research Sloan School of Management Massachusetts Institute of Technology SEP 2 4 L 1985 RECEsVED SUPPORTING SENIOR EXECUTIVES' MODELS FOR PLANNING AND CONTROL by Michael E. Treacy 1. Introduction By now the use of models successful documented and easily observable. in corporate decision making Mclnnes and Wooller [1977], Naylor and Schauland [1976], all Carleton [1982], and Traenkle, et al_ observed the accelerating use of decision support system support functional corporate planning. or used by needs in finance, Very few explicit senior executives marketing, - or formal operations - [Rockart and Treacy, Grinyer and [1975] have (DSS) Most of these models are built and used by mid-level packages. is well modeling analysts to management, and models appear to be built 1982]. If these are the people responsible for the formulation of broad strategies and the design of organizational control mechanisms, then it follows that explicit modeling has not had as much impact upon these areas as some proponents would desire. Yet, models reality, simplify these senior executives use models for planning and control. are intuitive abstractions the decision and of implicit. complex process, They decision to are mental contexts, identify that important Their representations executives variables, of use to and to generate and evaluate alternatives. built into a computer analyzed program, models, but they are models. They are not usually put down on paper, quantitatively, even or viewed as They are often simple and inelegant and may bear little relationship to "good theory," but they are arguably the most important models for planning and control, because they are powerful and they get used. As one executive put it: • I bring a lot of knowledge to the party. Just scanning the current status of our operations enables me to see some things that those with less time in the company would not see as important. [Rockart and Treacy, 1982] This executive These operation. clearly models well -developed many has allow him to quickly implicit assess in How well trouble because is this company doing? sales are declining. conrionly held implicit model But what if the time frame model is required these numbers may actually model of expected sales was much simply This conclusion represented is only pattern may These that illustrates 1 One reaction is that the firm is is that sales are always rising in sales only Figure his Looking at the sales performance reflected in the trend line, one this point. might ask: of information new someone less experienced would have to formally analyze. models indicate seasonality, to interpret the data. see a very lower. and a derived more a healthy company. twelve months? a from Then complex the informal An experienced executive looking at healthy This situation because example his illustrates or her that data becomes information when it is interpreted through some implicit model. models are nothing experience and knowledge. other than the accumulation of an individual's 3- Sales Time Figure 1 Analyzing Sales Data With Implicit Models -4- Does the executive really need an explicit or formal his analyzed using modeling range of techniques. a understood who Explicit models operations? her or Others operations. those of operations firm's the are easily might argue that they can a manager benefit by formal what the executive but support for his or her implicit modeling, needs is not formal models, be that even could well and shared Some would argue very to understand model so that the weaknesses of this abstract mental modeling can be reduced. This paper contributes toward the debate over whether senior executives should be supported with explicit models or by other measures. The answer depends upon the type of decision contexts faced is a simple one. by We analyze the nature of explicit and implicit models and the executive. alternatives for supporting these different modeling processes. this, the rest Our position of section discusses senior executives' paper the divided is into needs most important problems are complex that complete and formal The next and concludes that sections. several nature of executive analytic the To accomplish unstructured and and analyses of these problems are not always possible. The section concludes with a simple categorization of analyses that is later used to discuss alternate types of support systems. Section alternate 3 forms executives. of develops analysis of a set of criteria for evaluating the appropriateness of support This is may incur, done by for for different analytic examining the potential a alleviate or avoid such problems. of decision support systems. the major objective The final of needs of senior problems that each form support systems is to section discusses alternate forms These different forms derive from differences in •5- DSS tools, time some so devoted is to a discussion of these One tools. conclusion drawn in this section is that new» emerging forms of modeling, such as may provide support fuzzy modeling, for many of most senior executives' important analytic problems. The Nature of Senior Executive Analysis 2. There is a organizations, explanations of lot little but suggest of use formal of use themselves. models them may It planning for senior by control executives. senior that be and in Several executives do not building and analysis or for using possess the necessary skills for model a But Rockart and Treacy have found that even among senior executives computer. who use computers for analytic support there is little use made of explicit It may be that executives Models [1981, 1982]. don't need formal models; or that their information requirements are simple enough that ad hoc analysis is sufficient. are too Or, it may be quite the opposite, complex for explicit modeling to that the problems they confront be of much benefit. This third of senior possiblility we believe is often closest to the truth. Much has executives. with been written about the roles information and needs Mintzberg [1973] observed that senior managers are often dealing overwhelming computer-generated complexity under information was great of time little pressure. use to these He found people. that They preferred current and timely information that could be obtained only through informal channels. Gorry and Scott Morton [1971] build upon Anthony's [1965] -6- framework and characterized role the of senior executives They require support for defining largely unstructured. strategic as and generating problems, alternative solutions, and evaluating them against strategic criteria. issues that senior executives Most of the important planning and control must face, such as the creation of plans, the control of subordinates, or the analysis of competitive advantage, are highly dependent upon the exact context of the problem. They operating standard deal with Sufficient procedures. under great uncertainty. There and is no for complete Therefore, problems is very difficult to obtain. work problems unique which are there knowledge no these of senior managers must often "normative" approach planning to and control; there is no clear set of decisions which arise in the course of this process. as future Rather, data concerning both past and current results as well plans, are scanned and analyzed, variable decision opportunities occur. and As Charles a set of ad hoc , highly Hitch [1957] observed some years ago: The sort of simple explicit model which operations researchers are so proficient in using can certainly reflect most of the significant factors influencing traffic control on the George Washington Bridge, but the proportion of the relevant reality which we can represent by any such model or models in studying, say, a major foreign policy decision, appears to be almost trivial, [p. 718] Adding to the difficulties of what Bellman [1957] calls aspire to plan and control a lack of structure and great uncertainty is "the curse of multidimensional ity. " Managers may their firms for the single oDjective of long term -7- as present period profit plans and gaining X% of market share, along way. the Thus, there as milestones their independent and objective of long run profits is often not well relationship to the overall understood. not objectives are operational These such objectives, profitability, but in practice they require many operational further is introduced uncertainty multiple by and fuzzy evaluation criteria. We may conclude that the most important problems of planning and control These two faced by senior executives are complex and relatively unstructured. » characteristics, complexity and structure, define situations that is helpful executives. In Figure 2 a categorization of analytic in discussing alternate ways of supporting have we illustrated senior For categorization. this expository purposes, quadrants have been used to define four types of analytic The qualifier situations. "relatively" indicate that there has been used to are not clear demarcations between these categories. important problems The are analytic of planning illustrated situations in and the control upper faced by right senior managers are they quadrant: complex, relatively unstructured problems. In the lower left quadrant are situations analytic where extent the of knowledge about the problem is relatively complete and the problem is not very such In operating procedures quadrant complex. are problem situations, complex. analytic can often situations For these problems, be solving routinely that are is fairly applied. relatively easy In well the and standard upper structured, left but standard operating procedures or rules of thumb -8- PROGRAM COMPLEXITY relatively complex relatively simple relatively relatively structured unstructured PROBLEM STRUCTURE Figure 2 Four Types of Analytic Situations -9- typically in the form of an explicit analysis, Formal are often inadequate. model, is required to integrate many pieces of information in a structured way. difference The between problems can be illustrated with can problem be viewed as order quantity can economic simple a one, applied, be models are needed to pull formal problem of the to or inventory which as well -structured relatively of types two these rules such thumb of Material relevant information together. all It can requirements planning is an example of the latter view of the problem. be implemented with only the of aid large, Which models. formal as which for complex problem, a This reordering. view is appropriate for structured problems depends primarily upon the level of effort one wishes to expend to generate a satisfactory For unstructured solution. problems, it also depends upon what is and is not known about the problem. It is evident from the preceding examples that some problems can be viewed An inventory problem can as fitting in any of the four quadrants of Figure 2. be simple or complex, depending upon how it is viewed, and the greater one's experience and understanding of such problems, the more structure they appear to The more have. provide a unstructured the complete represention; important it is to provide a problem area, the more complex valid formal analysis. the given executives, a choice. by the nature of the problems able are the problem area, we to the more Thus, given a choice, one would opt for the most complete analysis and perhaps senior less a they formal face, analysis, are not but often -10- For each of the analytic illustrated situations analytic approaches can be applied. particular, In Figure in different 2, choose to one can explicit or implicit models to any of these types of problems. apply Which form of modeling is most appropriate for each type of analytic situation is examined in the next section by developing a list of strengths and weaknesses analytic These approach. lists are also used in subsequent the determine which form of support system is most appropriate for each section for each to type of analytic situation. 3. Potential Problems with Explicit and Implicit Models Little models are has developed a list of criteria robust, simple, easy control, to with, and as complete as possible. executives have been cases, and critical assumptions can all Good [1970]. to communicate implicit mental models to examine alternate scenarios, current observation negates part of account for what was observed. Subtle from observing relationships, models complex exceptional These And one can use them in many ways - as part of a information. a derived The mental be part of a good mental model. implicit models are also easy to control. with easy They can be robust. relationships and events over many years. conjunction adaptive, By these criteria, be carried around in a person's head. experienced models good They are simple, or at least simple enough that they can can be good models. of for larger analytic Mental models are process, adaptive. or in If manager's model, it will probably be modified to They are as complete as possible, as a manager has been able to comprehend. as complete II. can however, good models, for criteria Little's They can be viewed as a list of the potential way. Formal criteria. Little's meet easily so problems introduced when This would account for why mental implicit mental models are made explicit. models another interpreted be models tend be to complicated; they can sometimes give absurd results when certain complexities are only can They missing. controlled be They usually are difficult to facilities are built into the modeling system. adapt situations other to and information. new to whatever through exercised and explicit And models certainly are not easily communicated with by a typical manager unaccustomed to their use. Not all pick out the good ones. ills than That research El am, for et al_ But, why is those and formal to Will [1975] fomal models suffer more of these least at Or, their shortcomings are important and new models. Konsynski and Dolk is each present conceptual more of area an management model committed [1980], in general, models. informal do obvious. Little provided a list that helps to formal models are this bad. [1982], for schemes modeling systems that would help automatically to reduce some of the problems with explicit models. If these ideas could be implemented, then we might see more managers approaching problems using formal modeling methods because they would be perceived as more valuable relative to implicit mental models. Perhaps the most important limitation of mental models is that they do not handle complexity relationships remarkably well. between broad range It is variables. of difficult Our knowledge, integrators of that knowledge. but to mental people mentally integrate capacities are not can complex handle particularly a good 12- A problem second manipulate. Once a with implicit models these adequately describes model a that is are they hard to phenomenon, one might like to use it to predict or to optimize some aspect of the phenomenon. This requires manipulation of the model, trying alternative scenarios, assessing the impact of uncertainty, and all the other techniques that have become familiar through line-oriented systems. modeling This cannot done be as easily with as a formal mathematical model. Another problem with mental because experience. planning that is they are difficult to share And it is even harder to convey the supporting evidence for the with others. model models it This and often is is and gathered years through of important problem because the process of management an control intangible is a large and widespread undertaking. requires It specialists in particular areas, such as a strategic planning, accounting, and requires the insight, finance. In addition, it can be provided by only senior line analysis, management. Thus, and guidance which it is a shared activity, involving many different actors with only partly shared perspectives. A fourth problem with implicit models Mental models are difficult to validate. stems test against impartial information processors. mental models. evidence. This may result problems and one two. If they cannot easily be manipulated and if they cannot be easily shared with others, to from We in know then they are also difficult that imperfect, people perhaps are imperfect badly Without proper validation, these flaws may not surface. flawed -13- Finally, implicit models are vastly Managers underutilized. often know much more about situations than they bring to the decision-making processes of planning and control. There is a major, uncatalogued resource out there that is not being adequately utilized. In Figure 3 we have summarized the preceding discussion as a list of the primary potential of a support and mental problems with formal system executive modeling for is models. to A major objective alleviate some of these problems. Formal Models: * * * * * complicated and hard to understand difficult to make robust difficult to control difficult to adapt difficult to communicate with Mental Models * do not handle complexity well difficult to manipulate difficult to share difficult to validate uncatalogued and underutilized * Figure 3 Primary Potential Problems with Formal and Informal Models 4. Alternate Forms of Analytic Support Among all the buzzwords, jargon, and acronyms of the information field, decision support systems (DSS) has proven to be philosophical substance. As a practical matter, a systems term of practical and DSS focuses on the analysis of data and explicit modeling of the business and its environment. A manager 14- viewed is not as passive a infonnation, of consumer but active an as participant in the development and use of his or her personalized, supporting process development Adaptive design with manager and wants desires. are necessary user control to maintain, tenet the the the in to a process of of the direction the DSS Adaptive approach. parts those evolve involvement in, system a that supporting and manager's job. support begin job that that the or she he The user is assumed to be knowledgeable about his or her role and, if provided with the appropriate data, evolve will of fit to require and not just over, fundamental a perspective, user's the is design evolutionary user control Thus, computer system. equivalent better toward Lindblom's to software tools, training and guidance, management. It "muddling [1959] is information the through." This systems non-invasive, adaptive philosophy has been key to DSS's extraordinary practical success. During past the ten years, decision of host a support systems (DSS) generators and software packages have been developed that allow analysts and managers to differences forms of develop among analytic the and major support directly decision use categories presently support packages of available. define Figure systems. the 4, The alternative adapted from Montgomery and Urban [1969], shows the capabilities that have been provided by different DSS generators. A decision support system provides information on his or her internal an a manager and external interaction and display facility that may with another source business environment. include a of Through command language and query, report writing, and color graphics facilities, the manager can access a 15- MANAGER \ DECISION INTERACTION MODELS AND DISPLAY STATISTICS AND DATA BASE MANIPULATION 1 ENVIRONMENT Figure 4 Comprehensive DSS Capabilities -16- base of and functions, arithmetic, statistical, perform data, explicit create models his of other and her or data firm, manipulation competitors, industry, and the economy. Figure 4 represents an generator capabilities DSS set of ideal With . these capabilities it is now possible to build many different types of support systems. best for each of form of support is face is which The question we the different analytic situations discussed in Section 2? In Figure 5, four different forms of support are indicated for the four analytic situations. describe each of these forms of support and the rest of this section we will explain how they relieve problems potential the In explicit of and implicit models discussed in the last section. Model -Oriented DSS for Complex, Well -Structured Problems Complex problems that are with formal explicit models. enough knowledge to construct context. is the complex, Hence, analytic relatively well formal a a well -structured area, there is fairly complete representation of the problem of choice, problems system A should modeling environment in which modeling reduced. problem better analyzed modeling is possible and for significant problems it approach well -structured In structured are be is to aimed support toward the analysis providing easier and potential a of formal problems are -17- PROBLEM COMPLEXITY relatively complex relatively simple MODEL-ORIENTED DSS 18- focused support decision of the on just Many such form a generators system capabilities The support. of line-oriented modeling packages are diagrammed in Figure modeling line-oriented A gives spreadsheet, interrelated several time manipulate the that the model model, ability and analyses. These are known results assumptions defined line by line, with each of and line easily to and scenarios, systems over model the of model user the line-oriented electronic an as explicit an allow packages the alternate test the these of 6. define to calculate Typically, to commonly more are the in representing to sense another The packages usually allow a manager to define, solve, and analyze variable. model is the variables periods. perform sensitivity a manager a several system, available presently and generate reports and graphs. They do not, in general, manage a data base or offer ad hoc analytic capabilities. These line-oriented modeling systems have won many supporters, but they are still not user-friendly enough to have gained a significant base of senior executive users, except in financial the creation of formal to create also a address designed providing to a many make of the modeling powerful They are, however, ideal for models if the analyst has enough knowledge to be able complete fairly functions. but representation potential easier, problems less uncomplicated building and model analysis commands. of the with problem. formal complicated, syntax that and These models. more incorporates packages They friendly both are by model 19- -20- The command languages used in this type of software also make it easier to control Changing models. data values, performing different analyses, and changing the format of printouts are all easier with these packages than with a standard programming language. Because the models are syntactically less complicated and easier to understand, they are also easier to adapt. The one potential problem that these packages do not help to alleviate is the difficulty in making might be used to create a only a language and has formal models For example, robust. this software sales forecasting model, but because the package is no built-in intelligence about sales forecasting, it can in no way assure that the model is correct. These modeling line-oriented accounting-based models in fairly systems are well-understood used areas, such evaluation of projects, budgeting, and consolidation analysis. understand enough accounting to be able to evolve useful models through an interactive process of model one way that the semantic potential problems as financial Most managers and usable financial building and analysis. of for extensively formal models have Thus, been overcome is by basing the models upon well -understood accounting principles. Data-Oriented DSS for Simple, Well -Structured Problems Simple and well -structured monitoring and tracking sales, data that they can use to problems are for example, trigger rules fairly easy what managers of thumb or to need support. is standard access In to operating -21- This is the type of support offered by data-oriented DSS. procedures. These systems are built to provide managers with ready access to a pre-defined base They are often used as supplements for paper-based reporting systems of data. because they offer more flexible reporting formats as well as a limited set of These systems are used to support monitoring in areas where analytic tools. an executive has fairly well -formed mental a But because the data covers only limited area and analytic tools are also a appropriate only are DSS data-oriented limited, performance. of expected model recurring, for reasonably-structured problem areas such as monitoring performance vs. budget. The software that data-oriented decision support systems are based upon is quite different usually called management in RAMIS, software the "friendly" systems illustrated FOCUS, from (DBMS). Figure NOMAD, (that The Some 7. for model -oriented used is, easy to capabilities well-known and DBASEII. These of and learn this products packages systems. use) class in provide a data base software are marketplace are of the is It manager with a facility for managing and accessing a large base of data, creating reports and graphs, and performing very limited analysis upon the data. They give managers the ability to choose the data that they wish to see and to format it in reports or graphs as they wish to the line-oriented modeling software, see it. Unfortunately, as with much of the user interfaces for these data base packages are not yet friendly enough to encourage widespread use by executives. •22- •23- Infonnation Support for Simple, Unstructured Problems difficult more the more unstructured they are, for relatively simple problems, Even becomes it used to address problems relative Concurrently, for support. appropriate to pre-define to such subject become must be based upon at least three design elements: a that are firm is doing validity, questionable to are Support for simple but unstructured problems manipul ability, and sharability. (2) models as succession planning or how a competition its implicit mental the that reports and data the the (1) large base of data, a set of ad ho£ analytic tools, and (3) sharing of the system by managers These design with common information needs. support system, which the is most elements define form implemented widely information an of support for senior executives. an In increasing number of companies, of level a and data software commonality have been established; their information support systems resembles Figure 8. naturally planners Bases of data have been established for groups of individuals who draw and the upon same controllers type created of one data. In base of managers and market researchers created another. Chicago, corporate staff [Rockart and Treacy, 1982] and In executives all both firms, data, At draw it was company, one while one strategic the marketing Industries Northwest from the base the managers of in data. and analysts who established what data would be in the data bases and what data definitions would be used. And, despite the common data bases, also maintain their own personal data files. in every case the users -24- USER INTERFACE Specific 25- With present information requirements analysis These data bases evolve. techniques and with the existing state of data management in most firms, only about half the needed data can be put into data base on the first pass. a In addition, the nature of the executive's job is one of constant change and new data are often needed to support new problems and opportunities. Each of these three design elements helps the manager against the data. models. are build, to In explore and test his or her models implicit this way, data analysis serves to help validate mental One of the potential difficult to reduce problems of validity A large base of data combined with analytic tools and sharing mental models. allows to share, problems with these implicit models is that they difficult to transfer to another person. A shared information support system provides a language and a medium for communicating If managers support their implicit models through a system, implicit models. then the models become more transferable with the sharing of data and analysis. The data software management that underlies and ad hoc information analysis support capabilities. systems The comprehensive and contain all the elements shown in Figure must have packages both must be 4. Fuzzy Modeling and Expert Support for Complex and Unstructured Problems Most implicit mental models are fuzzy, but computer-based modeling systems are precise. computer-based Until we can develop fuzzy modeling systems, most of the useful, support for implicit models will be provided through data -26- and analysis, retrieval, the Fuzzy modeling systems will internal inconsistent and transfonning allow a different into formats. manager to externalize crude, incomplete, without models data of having complete and internally-consistent models like those to translate found in into them model -oriented DSS. Fuzzy models are used by senior managers all pricing decision, (2) (3) of manager might bring into play the following rules: statements these is in form a precise enough fuzzy modeling system, however, the above statements form decision that could be solved. satisfactory, but it is a to be used Each statement begs for refinement. standard formal modeling system. be in a Our price should be about two times direct costs. Our price should be just below our dominant competitor's price. If our competitor's prices go too high, we should price for increased market share. (1) None a For example, the time. model a in a With a of a pricing The results of that solution clearly would not useful starting point that prompts the manager for a more refined representation of his or her mental model. Fuzzy models problems, with. complexity. potential type the These are of models But, flaws of ideally suited problems have the fonnal precision and consistency. that power conceptually, models complex to senior of fuzzy such as the relatively executives formal models and must modeling compensate requirements unstructured commonly systems for to many deal handle of the for completeness, -27- Fuzzy modeling systems can create and analyze models that are incompletely these for compensate systems ambiguous in their the models by intelligently or inconsistent, internally specified, flaws in assumptions added automatically are model the to choosing Along with the results, assumptions that will allow the model to be analyzed. these The causality. shown and the to manager who can modify them for further analysis. The development of fuzzy modeling systems might sound as if is many years away. The technology for fuzzy modeling has been developed in the It is not. intelligence artificial product already has an community approximate and widely becoming is reasoning provides that capability One available. some fuzzy modeling features. intelligence community, Another important development from the artificial relevant the to support of complex relatively situations, is human expert systems. assistants computer. a reorient the applications toward to that can support rather than A recent development providing computer-based expert replace a of the data, taking For maker. decision example, one company has developed "smart" statistical tools. is given sales data, decision unstructured To date, such systems have been oriented toward replicating expert capabilities on has been and When a computer for instance, the system will analyze the characteristics into account such things as seasonality, and will then choose the most appropriate sales forecasting tool. The conceptual under the rubric underpinnings of expert support systems have been developed of "model management systems." According to El am, et al_ -28- [1980], a model management system, can be viewed as a system that dynamically constructs a This is decision aid in response to a particular problem. accomplished by drawing on a knowledge base of models that captures the technical expertise of a management scientist plus an understanding of the basic activities involved in a given decision-making environment... These fuzzy modeling and expert support tools are not yet available. is little wonder, modeling needs problems. Of are the meaningful of therefore, popular faced executive for difficulty had complex with support a problems, the unstructured and support systems because systems models. support mechanism for complex problems. senior managers might feel supporting information support, support for a manager's implicit mental support fails as "real" executives senior have we three other forms of the most that It offer they But, information That is why many that executive support cannot help them with their their complex For them, problems. must wait we little a longer for the emergence of some "real" executive support tools. 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