Operations Management: Decision Making, Modeling, and Supply Chain Notes
Decision Making in Operations
- Marketing group develops a new product (market selection, basic design) and hands it to the operations manager to determine the execution plan.
- Operations manager's decision questions cover:
- What, when, where, how, and who will do the work
- Resources needed and how much, where and when each resource is needed
- A series of "whens": scheduling of work, ordering of materials, and the design sequence
- Core decision areas illustrated by a simple product example (a doll):
- Whether to make components in-house or contract out
- If in-house, whether to dedicate machines for left arm vs right arm
- Eyes, clothes, and other parts: whether to buy or produce in-house
- Level of hand finishing and the required quality control
- Takeaway: The basic product idea comes from marketing; the operational plan is about how to realizethe product efficiently and at desired quality and cost.
- A model is an abstraction of reality and can take several forms:
- Physical model: e.g., a miniature house
- Schematic model: blueprints or charts
- Mathematical model: abstract formulas and computations (e.g., queuing theory)
- Example of a mathematical model: queuing theory can model the probability of a customer not waiting given the number of customers in the line.
- In the doll example, the appropriate model type is a schematic of the processes needed to reach the end product (process flow diagram).
- Why understand how a model works:
- To trust and effectively use the model for decision making
- To recognize when something in the model is out of sync, rather than blindly following the computer’s output
- Partial quote paraphrase: it’s not enough to say, “The computer is telling me the answer”; you must understand the processes behind it.
- Key questions to develop a model:
- What is the purpose of the model? (objective)
- How will the model generate results? (mechanism)
- How will results be interpreted and used? (actions)
- What are the model’s assumptions and limitations? (scope and constraints)
- Garbage In, Garbage Out (GIGO): bad data lead to invalid results. The data quality directly affects model validity.
- Real-world data quality examples:
- Experian study: bad data directly impacts the bottom line for about 90% of American companies
- IBM report: US organizations believe an average of 32% of their data is inaccurate
- Estimated revenue impact: average loss of about 12% due to bad data
- NASA Mars Orbiter Mission (1999): imperial units vs metric units caused a $125,000,000 error due to data inconsistency
- Trusting models requires understanding data quality and the model’s function; otherwise, decisions may be flawed even if the model seems authoritative.
- The value of models:
- Cheaper and easier than testing in real systems
- Forcing users to quantify information
- Allows scenario analysis and "what if" questions (e.g., impact of a Bucks win vs. loss on Tampa police operations)
- Caution with models:
- If a model’s prediction is too perfect, there is likely a mistake
- The black box problem: users may not understand what is happening inside the model, leading to unreviewed mistakes
- Always strive to know what data are being used and how the model operates; avoid relying solely on outputs
- Summary: models help structure problem solving, enable mathematical reasoning, and support repeatable analysis across similar scenarios, but require good data, transparent workings, and critical validation.
Quantitative Approaches to Decision Making
- In addition to models, quantitative methods seek mathematically optimal solutions and include:
- Linear programming
- Forecasting techniques
- Queuing theory
- Inventory models
- Statistical models for reliability
- These quantitative tools enable rigorous analysis and optimization of operations, but rely on correct assumptions and accurate data.
- Performance metrics used to manage and control operations include:
- Profits
- Flexibility
- Costs
- Inventory levels
- Quality
- Schedules (timeliness)
- Productivity
- Forecast accuracy
- Forecast accuracy example:
- Compare forecasted units sold to actual units sold to assess model validity
- Trade-offs: decision-making often involves giving up one objective to gain another (e.g., holding more inventory to improve service levels but incurring higher costs).
- Inventory considerations in trade-offs:
- Higher inventory costs can be offset by improved customer service and reduced stockouts, accommodating random variability in demand or supply
- Systems thinking: a holistic approach where interrelated parts must work together; the whole is greater than the sum of its parts.
- Subsystems include marketing, operations, and finance
- Changes in one area impact the entire organization (e.g., self-checkout affects customer experience, staffing, pilferage, software, and add-on sales)
- Pareto principle (the 80/20 rule):
- A few factors account for the majority of effects; focus on the critical few factors that drive 80% of outcomes
- Expressed as: ext{Pareto principle: } 80 ext{\% of effects come from } 20\ ext{\% of causes.}
- The six approaches will be used across the course to analyze diverse problems.
Key Issues for Operations Managers Today
- Global economic conditions and rapid innovation: need to adapt quickly to changing markets
- Quality assurance and quality control: customers have many options; poor quality leads to returns and customer switching
- Risk management: ensuring processes are reliable and resilient against disruptions
- Economic conditions and global competition: customers can source from anywhere; competitive pressures are high
- Ethical considerations in operations:
- Corporate finances, worker safety, product safety, environmental sustainability, workers' rights, and hiring/firing practices
- Ethical issues arise across operations, including finance, safety, product quality, and sustainability
- Sustainability: using resources in ways that do not harm ecological systems; sustainability practices can enhance brand value and profitability
- Supply chain considerations: moving beyond internal operations to manage suppliers and their suppliers
- Problems upstream can trigger downstream disruptions (the supply chain domino effect)
- Example of supply chain risk: a silicon shortage impacts semiconductor delivery
- Supply chain management realities:
- Need to improve operations and enable easy interchangeability of similar resources during shortages
- Increasing outsourcing and transportation/logistics costs
- Heightened globalization and the growth of e-business (global market access)
- Supply chain complexity: multiple moving parts across borders and stages must coordinate to deliver products on time
- Inventory management goal: ensure customers can obtain goods when they want them, avoiding stockouts while controlling carrying costs
- Final takeaway: Operations management and supply chain management involve navigating global dynamics, ethical considerations, and complex interdependencies to sustain customer satisfaction and organizational performance
Doll-Factory Analogy and Process Design Notes
- The doll example demonstrates decision points about process design and outsourcing:
- Decide on in-house manufacturing vs. outsourcing for parts (left arm, eyes, clothes, etc.)
- Determine the extent of post-production finishing and quality control requirements
- This analogy helps illustrate how process decisions feed into the overall operations strategy and cost structure
Practical Implications and Real-World Relevance
- Understanding models helps managers explain, defend, and adjust decisions in marketing, operations, accounting, finance, and technology
- Data quality is critical across domains; inaccurate data can lead to suboptimal or damaging decisions
- A systems approach fosters cross-functional collaboration and aligns incentives and outcomes across departments
- The Pareto principle helps prioritize improvement efforts on the factors that have the most impact on performance
- Global supply chain awareness is essential for risk mitigation, cost control, and customer satisfaction in a worldwide marketplace