APR 02 1990 SUPPORTING SENIOR EXECUTIVES' MODELS FOR PLANNING AND CONTROL Michael E. Treacy 90s: 85-008 Management in the 1990s SUPPORTING SENIOR EXECUTIVES' MODELS FOR PLANNING AND CONTROL Michael E. Treacy 90s: 85-008 June, 1984 CISRWP#125 Sloan ® This paper appears in WP# 1676-85 M. E. Treacy The Rise of Managerial Computing: The Best of the Center for F Rockart and C. V. Bullen, eds., Dow Jones-Irwin, Homewood, J Information Systems Research, Illinois, 1986. Management in the 1990s Sloan Scnool of Management Massachusetts Institute of Technology Management in the 1990s is an industry and governmental agency supported research program. Its aim is to develop a better understanding of the managerial issues of the 1 990s and how to deal most effectively with them, particularly as these issues revolve around anticipated advances in Information Technology. Assisting the work of the Sloan School working partners in scholars with financial support and as research are: American Express Travel Related Services Company Arthur Young and Company British Petroleum Company, p. I.e. BellSouth Corporation Equipment Corporation Eastman Kodak Company General Motors Corporation International Computers, Ltd. MCI Communications Corporation United States Internal Revenue Service Digital The conclusions or opinions expressed in this paper are those of the author(s) and do not necessarily reflect the opinion of Massachussetts Institute of Technology, Management in the 1990s Research Program, or its sponsoring organizations. SUPPORTING SENIOR EXECUTIVES' MODELS FOR PLANNING AND CONTROL by Michael E. Treacy 1. Introduction By now the successful use of models documented and easily observable. in corporate Mclnnes and decision making is well Carleton [1982], Wooller [1977], Naylor and Schauland [1976], and Traenkle, et all observed accelerating use of decision support system functional corporate planning. needs in Very few explicit or used by senior executives marketing, finance, - or formal operations - [Rockart and Treacy, [1975] have (DSS) Most of these models are built and used by mid-level packages. support the al_ Grinyer and modeling analysts to and management, 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 are senior executives use models for planning and control. intuitive abstractions the decision and of implicit. complex process, They decision to are mental contexts, identify that important Their representations of use to and to executives variables, They are not usually put down on paper, generate and evaluate alternatives. built into a computer analyzed program, quantitatively, even or viewed as They are often simple and inelegant and may bear models, but they are models. 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 Just bring a lot of knowledge to the party. 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 clearly executive operation. These models well-developed many has allow him to quickly implicit someone less experienced would have to formally analyze. in Figure How well trouble because is this company doing? sales are coimionly held implicit model that illustrates 1 declining. One reaction is that the firm is This conclusion is that sales are always rising in a derived sales pattern may model is required to interpret the data. these numbers may actually model of expected sales was much only becomes models simply indicate see a seasonality, very lower. and a more from a healthy company. But what if the time frame represented is only twelve months? These his Looking at the sales performance reflected in the trend line, one this point. might ask: of infomation new assess models Then complex the informal An experienced executive looking at healthy situation because This example his illustrates or her that data information when it is interpreted through some implicit model. 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- to understand Does the executive really need an explicit or formal model his analyzed using modeling of range of techniques. a understood who Explicit models operations? her or operations firm's the easily ^ery argue can a manager benefit by formal that what the executive but support for his or her implicit modeling, needs is not formal models, be that even could well they and shared Some would argue Others might operations. those are 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. We analyze the nature of explicit and implicit models and by the executive. alternatives for supporting these different modeling processes. this, the section rest Our position of discusses senior executives' paper the the nature divided is into of executive The next needs and concludes that several analytic most important problems are complex that complete and formal To accomplish sections. 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 3 develops a set of criteria for evaluating the appropriateness of alternate forms executives. of analysis of support for the different analytic This is done by examining the potential may incur, for a alleviate or avoid such problems. of decision support systems. 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- tools, DSS 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 fuz^ modeling, may provide support for many of most senior executives' important analytic problems. 2. The Nature of Senior Executive Analysis There is a organizations, explanations of lot little but suggest of use formal them of use themselves. models may It senior by control in Several executives. senior that be and planning for 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 don't need models [1981, 1982]. fomal 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- and framework characterized largely unstructured. role the of senior executives strategic as and generating They require support for defining 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. operating standard They deal with Sufficient procedures. problems is very difficult to obtain. work under great uncertainty. problems unique There and complete Therefore, is no for which there knowledge are 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 objective of long term -7- objectives, profitability, but in practice they require many operational as present period profit plans and gaining X% of market share, along the way. Thus, there as milestones independent and their objective of long run profits is often not well relationship to the overall understood. not objectives are operational These such further is introduced uncertainty by multiple and fuz?y 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 a categorization of analytic situations that is helpful executives. In Figure 2 in discussing alternate ways of supporting senior have we illustrated categorization. this For 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 and the in control upper faced by right senior managers they quadrant: are complex, relatively unstructured problems. In the lower left quadrant are situations analytic where extent of the knowledge about the problem is relatively complete and the problem is not very In operating procedures quadrant complex. are such 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 •••• •••ai relatively simple •••I relatively relatively structured unstructured PROBLEM STRUCTURE Figure 2 Four Types of Analytic Situations •9- Formal are often inadequate. typically in the form of an explicit analysis, model, is required to integrate many pieces of information in a structured way. difference The between these problems can be illustrated with can problem be viewed as simple a economic order quantity can problem of the one, applied, be formal models are needed to pull to or inventory which as well -structured relatively of types two rules thumb of such 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 for which 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 solution. For unstructured 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. and the greater one's be simple or complex, depending upon how it is viewed, 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 given executives, a choice. by the valid formal analysis. nature able are the more complex the problem area, of the problems 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 the of illustrated situations analytic analytic approaches can be applied. In particular, Figure in different 2, one can choose explicit or implicit models to any of these types of problems. to 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 for each lists are These analytic approach. also used in subsequent the section to determine which form of support system is most appropriate for each type of analytic situation. Potential Problems with Explicit and Implicit Models 3. Little models are has developed simple, a list robust, easy criteria of control, to with, and as complete as possible. executives have derived been cases, and critical assumptions can all to examine alternate scenarios, current observation negates part of a a Subtle to Good communicate implicit mental models from The mental models observing relationships, complex exceptional These And one can use them in many ways as part of information. account for what was observed. as [1970]. 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 a 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 complete manager has been able to comprehend. -11- criteria Little's can however, good models, for They can be viewed as a list of the potential way. models 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 tend be to complicated; they can sometimes give absurd results when certain complexities are They missing. only can controlled be They usually are difficult to facilities are built into the modeling system. adapt situations other to and explicit And information. new to whatever through exercised and models certainly are not easily communicated with by a typical manager unaccustomed to their use. Not all pick out the good ones. than ills That research Elam, for et al_ But, why is those [1980], and at Or, least formal to Will [1975] their suffer more of these shortcomings are important and new models. Konsynski and Dolk is each present conceptual more of area an management model conmiitted formal models 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 manipulate. with problem second implicit models these adequately describes Once a model a is that they to phenomenon, one might like to use it to predict or to optimize some aspect of the phenomenon. This requires trying alternative scenarios, assessing the impact manipulation of the model, the other techniques that have become familiar through of uncertainty, and all modeling line-oriented hard are This systems. cannot done be as easily with as a formal mathematical model. Another problem with mental because planning it This experience. that they are difficult to share And it is even harder to convey the supporting evidence for the with others. model models is is intangible and gathered important problem because an control and often is is a large and the widespread years through of process of management undertaking. requires It specialists' in particular areas, such as a strategic planning, accounting, and finance. can only In addition, be provided it requires the insight, by 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 from problems one and two. If they cannot easily be manipulated and if they cannot be easily shared with others, then they are also difficult to test against impartial information processors. mental models. evidence. This may result We in know that imperfect, people perhaps are imperfect badly Without proper validation, these flaws may not surface. flawed -13- Finally, implicit models are vastly underutilized. Managers 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 problems with formal system and mental 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 Potenti al Probl ems wi th Formal and Informal Models 4. Alternate Forms of Analytic Support Among all the buzzwords, jargon, and acronyms of the information systems field, decision support systems (DSS) has proven to be a term of practical and philosophical substance. As a practical matter, DSS focuses on the analysis of data and explicit modeling of the business and its environment. A manager -14- not viewed is as passive a consumer information, of but as active an participant in the development and use of his or her personalized, supporting process development is necessary Adaptive design and user control with perspective, user's the manager wants desires. to maintain, require system a that the the in manager's a of process parts those evolve to the of the DSS Adaptive approach. the of fit to direction support job that and job. begin that the or she he The user is assumed to be knowledgeable about his or her role and, if provided with the appropriate data, better toward evolve will tenet supporting and not just involvement in, over, fundamental a are design evolutionary user control Thus, computer system. equivalent 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, a host decision of 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 categories presently decision use packages of available. support 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 a manager with another source information on his or her internal and external business environment. an interaction and display facility that may of Through include a command language and query, report writing, and color graphics facilities, the manager can access a > -15- MANAGER DECISION MODELS i — Y I INTERACTION AND DISPLAY STATISTICS AND DATA BASE MANIPULATION 1 ENVIRONMENT Figure 4 Comprehensive DSS Capabilities •16- base of data, and functions, statistical, perform explicit create arithmetic, models and his of data manipulation firm, competitors, other her or industry, and the economy. Figure 4 represents an ideal generator capabilities DSS set of With . these capabilities it is now possible to build many different types of support systems. The question we the different analytic face is which form of support is best for each of situations discussed in Section 2? In Figure 5, four different forms of support are indicated for the four analytic situations. the rest of this section we will explain how they relieve the In describe each of these forms of support and potential problems 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. relatively well In a structured are well -structured problem better analyzed area, there is enough knowledge to construct a fairly complete representation of the problem context. is the complex, Hence, analytic fomal modeling approach well -structured modeling environment reduced. in of is possible and for significant problems it choice. problems should which modeling system A 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 spreadsheet, gives interrelated several time manipulate manager a several model, to model calculate alternate These are the results line-oriented reports and graphs. and generate They do not, of of model over model the user easily to scenarios, systems defined line by line, with each line electronic an as the and assumptions these of explicit an allow packages the known define to are 6. in and the to sense representing another The packages usually allow a manager to define, variable. a is and test commonly more ability Typically, perform sensitivity analyses. that the model the variables periods. the system, available presently and analyze solve, in general, manage supporters, but they a data base or offer ad hoc analytic capabilities. These line-oriented modeling systems have won many 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 many designed providing to a make of the modeling powerful however, ideal for models if the analyst has enough knowledge to be able complete fairly They are, functions. but representation potential easier, problems less uncomplicated building and model analysis commands. of the with formal complicated, syntax that These problem. and models. more incorporates packages They friendly both are by model -19- -20- The conmand languages used in this type of software also make it easier to control data Changing models. values, different performing analyses, and changing the fomiat of printouts are all easier with these packages than with a standard programming Because the models language. 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 difficulty the in making might be used to create a formal models For example, robust. this software sales forecasting model, but because the package is only a language and has no built-in intelligence about sales forecasting, it can in no way assure that the model is correct. modeling line-oriented These accounting-based models in fairly systems used are well -understood areas, for extensively such evaluation of projects, budgeting, and consolidation analysis. as financial Most managers understand enough accounting to be able to evolve useful and usable financial models through an interactive process of model one way that the semantic potential problems building and analysis. of 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 to support. In what managers need is access to of thumb or standard 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 model of expected performance. But because the data covers only a limited area and analytic tools are also data-oriented limited, DSS for appropriate only are recurring, 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. is, and well-known and DBASEII. performing very easy to capabilities facility for managing and accessing graphs, for model -oriented used These of" learn this products systems. and use) class in packages provide a data base software are marketplace are of the is It manager with a large base of data, creating reports and a 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 see the line-oriented modeling software, 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- Information Support for Simple, Unstructured Problems the more unstructured they are, Even for relatively simple problems, difficult more appropriate becomes it relative Concurrently, for support. used to address problems to its pre-define to implicit mental the succession planning or how such as competition become subject models are that are firm is doing a questionable to must be based upon at least three design elements: a that validity, Support for simple but unstructured problems manipul ability, and sharability. (2) reports and data the the large base of data, a (1) set of ad hoc analytic tools, and (3) sharing of the system by managers with common information needs. support system, which the is These design elements most widely define form implemented information an of support for senior executives. In an increasing number of companies, level a of 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 upon the 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, while from one the strategic the marketing Industries At Northwest draw it was company, one base the managers and of in data. 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 a data base on the first pass. 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 to reduce problems of validity A large base of data combined with analytic tools and sharing mental models. allows the manager against the data. models. are build, to explore test his or her implicit models this way, data analysis serves to help validate mental In problems with these implicit models is that they One of the potential difficult to share, difficult to information support system provides If managers implicit models. and a transfer to another person. A shared language and a medium for communicating support their implicit models through a system, 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 transforming 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 them into in model -oriented DSS. Fuzzy models are used by senior managers all pricing decision, (2) (3) of manager might bring into play the following rules: 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, in a the time. these statements is standard formal modeling system. in form a precise enough to be used Each statement begs for refinement. in a With a fuzzy modeling system, however, the above statements form a model of a pricing decision that could be solved. be satisfactory, The results of that solution clearly would not but it is a useful starting point that prompts the manager for a more refined representation of his or her mental model. Fuzzy models problems, with. the These complexity. potential are type of models But, flaws of ideally suited problems have the formal precision and consistency. models senior that power conceptually, complex to 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 for compensate systems inconsistent, internally specified, these ambiguous in their the models by intelligently or flaws in assumptions that will allow the model to be analyzed. these assumptions automatically are added The choosing Along with the results, model the to causality. and shown the to manager who can modify them for further analysis. The development of fuzzy modeling systems might sound as if is many years away. It is not. artificial product The technology for fuzzy modeling has been developed in the community intelligence already has an and approximate widely becoming is reasoning capability available. provides that One some fuzzy modeling features. Another important development from the artificial relevant the to support relatively of situations, is human expert systems. complex assistants that can and unstructured decision To date, such systems have been oriented toward replicating expert capabilities on has been to reorient the intelligence community, a computer. A recent development applications toward providing computer-based expert support rather than replace a decision example, one company has developed "smart" statistical tools. For maker. When a computer IS given sales data, for instance, the system will analyze the characteristics of into the data, taking account such things as seasonality, and will then choose the most appropriate sales forecasting tool. The conceptual underpinnings of expert support systems have been developed under the rubric 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 the therefore, with executive support complex models. support fails as a support mechanism for complex problems. "real" problems, offer they But, information That is why many that executive support cannot help them with their complex their the unstructured and because systems support for a manager's implicit mental senior managers might feel supporting infomation support systems other forms of support, for popular most faced difficulty had have we executives senior three that It problems. For them, must wait we little a longer for the emergence of some "real" executive support tools. 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