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This research paper explores the use of a subjective system dynamics model to simulate the impact of key strategic decisions on a Bulgarian winery transitioning from a centrally planned to a market economy. It discusses the concepts of open systems theory, cybernetics, mental models, system dynamics, and soft systems theory and explains the development and results of the winery model. The paper was presented at a symposium in Svishtov, Bulgaria in May 2002.
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Strategic Decision Making: A Systems Dynamic Model of a Bulgarian Firm David L. Olson, University of Nebraska Madeline Johnson, Univ. of Houston-Downtown Margaret F. Shipley, Univ. of Houston-Downtown Nikola Yankov, Tsenov Academy of Economics
Transition Economies • Transition from centrally-planned to market economies • Face ambiguous information and cues • Challenge existing ownership & operating principles • Firms responsible for strategic decisions
Joint Effort • University of Houston-Downtown • NSF Grant – Joint International Workshop on the Use of Information Technologies in Modeling the Bulgarian Firm in Transition from a Planned to a Free Market Economy • Tsenov Academy of Economics • Svishtov, Bulgaria
Subjective System Dynamics Model • Winery • Tool to simulate impact of key strategic decisions: • Market selection (local, national, international) • Promotion & pricing • Product quality decisions • Capacity (vineyards and bottling) • Distribution
Open Systems Theory • Ludwig von Bertalanffy • An organization exists in relation to its environment • There is a continuous flow of energy & information • System features: • Self-organization - progressive differentiation • Equifinality – initial condition doesn’t matter • Teleology – systems are purpose-driven
Cybernetics • Stafford Beer • Cybernetic systems are complex, probabilistic, self-regulatory, purposive, have feedback and control • Operations research only works when you consider the whole • Viable System Model – organization regulated, learns, adapts, evolves, or doesn’t survive
Mental Models • Systems consist of interacting parts working toward some end, feedback control • Purposive • Synergistic • Complex • Feedback
System Dynamics • Jay Forrester • Developed technique for deterministic simulation of systems • Identify influences • Estimate effects • Develop feedback model
Forrester’s World Dynamics Model • Sectors • Population • Natural Resources • Capital Investment • Pollution • Metrics • Quality of life • Material standard of living • Ratios for FOOD, CROWDING, POLLUTION
Soft Systems TheoryPeter Checkland • Interpretive action research • Model interacting system • Define problem done • Express situation done • Root definition • Conceptual model done – simulation model • Compare model/real world • Use model to determine improved methods • Action
Simulation Approaches • DYNAMO/Ithink/Stella/PowerSim • VENSIM • Commercial implementation of system dynamics • Support conceptual modeling • EXCEL • Probabilistic simulation over time • CRYSTAL BALL • Probabilistic simulation output
Development of Model • Symposium in Svishtov, Bulgaria • May 2002 • About 20 from U.S., 20 from Svishtov • Selected winery because of knowledge of Tsenov Academy faculty • Selected system dynamics because: • Problem involved subjective data • Complex interactions among decisions, time
Winery Model • Time frame: 6 years • Show impact of strategic decisions • Inputs: • Promotion • Pricing • Quality (grow or purchase grapes) • Market selection (local, national, international) • Outputs • Profit • Cash flow • Market share by product (3 levels of quality)
Promotion • Lagged over three month • Impact differentials • 0.5 prior month • 0.35 two months prior • 0.15 three months prior • Media: firm representatives interacting with distributors • Management could constrain local, national, or export markets to emphasize others • Demands in each market probabilistic
Quality • If winery controls vineyard, quality higher • Constrained by amount of hectares in vines • Three years between planting, use • Use own grapes as much as possible • Any extra production capacity used for purchased grapes (lower quality bottles)
System Variables • Exogenous: • System Variables: • Control Inputs:
Exogenous Variables • Demand (normally distributed, change per month) • By market (local, national, export) • By product (correlated) • Seasonal • Market Price (normally distributed, change per month) • Independent of firm decisions • Competitor promotion (normally distributed by market) • Market share possibilities • Prior market share multiplied by ratio of prior promotion to base promotion, divided by that of competitors • Crop yield
Control Inputs • Price • By product by month • Promotion • By product by month • Plant Capacity • Depreciation, plus construction • Labor • Permanent (higher quality) vs. temporary
System Variables • Sales • By market, by product • Inventory • High, low quality • Bank Balance • 5% gain on positive balance, 15% cost on negative
Results • Varied prices, promotion levels • Price: base, cut 10%, increase 20% • Promotion: base, emphasize local, emphasize export • Measured • bank balance after 6 years • Probability of losing initial capital (going broke) • Probability of breaking even • Market share (low, high quality)
Base Model • 1000 replications • Crystal Ball software • Cyclical demand for high quality • Base case has National focus • Without pricing & promotion, loss
Bank Balance • Mean 117,458 Lev • Probability of losing bankroll: 0.0 • Probability of losing money: 0.0 • Most optimistic: • Worst: loss:
Model Validation • Initial visit May 2002 • 3 day workshop to build model • Built model summer 2002 • Followup visit October 2003 • Went over model in detail • Refined model structure • Identified detailed data needs
Conclusions • System dynamics useful to model subjective input, complex interactions in temporal environment • Need for validation