cs249r_book/labs/plans/vol1/lab_15_responsible_engr.md

📐 Mission Plan: 15_responsible_engr (Responsible Engineering)

1. Chapter Context

• Chapter Title: Responsible Engineering: Ethics & Governance.
• Core Invariant: Lifecycle TCO & Carbon Economics (Inference TCO \gg Training TCO).
• The Struggle: Understanding that "Responsibility" is an engineering optimization problem, not just a policy statement. Students must navigate the trade-off between Fairness/Privacy (Algorithmic constraint) and Economic/Environmental TCO (Machine constraint) over a 3-year operational horizon.
• Target Duration: 45 Minutes.

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2. The 4-Track Storyboard

Track	Persona	Fixed North Star Mission	The "Responsibility" Crisis
Cloud Titan	LLM Architect	Maximize Llama-3-70B serving.	The Carbon Bill. Your fleet of H100s consumes 50MWh/year. The Sustainability Lead demands a 30% reduction in carbon footprint without dropping model quality.
Edge Guardian	AV Systems Lead	Deterministic 10ms safety loop.	The Disparity Crisis. Disaggregated evaluation reveals the model is 40x more likely to misidentify pedestrians with dark skin tones in low-light. You must fix the 'Safety Gap'.
Mobile Nomad	AR Glasses Dev	60FPS AR translation.	The Privacy Paradox. Users want real-time translation but won't accept local video storage. You must implement 'Differential Privacy' which adds 5ms of noise-overhead to your 10ms budget.
Tiny Pioneer	Hearable Lead	Neural isolation in <10ms under 1mW.	The Demographic Soundstage. Your noise isolation model works for studio-recorded male voices but fails for children and female speakers in home environments.

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3. The 3-Part Mission (The KATs)

Part 1: Disparity Discovery (Exploration - 15 Mins)

• Objective: Identify algorithmic bias through Disaggregated Evaluation.
• The "Lock" (Prediction): "If the 'Global' accuracy is 98%, can any specific demographic subgroup have an error rate higher than 10%?"
• The Workbench:
  • Action: Select different Data Slices (Gender, Age, Skin Tone, Acoustic Environment).
  • Observation: The Disparity Bar Chart. Watch the "Global" average hide the catastrophic failures in the "Minority" slices.
• Reflect: "Reconcile the result with the 'Gender Shades' study from the text. Why is aggregate accuracy a misleading metric for safety-critical systems?"

Part 2: The Price of Fairness (Trade-off - 15 Mins)

• Objective: Balance Accuracy vs. Fairness using the Pareto Frontier.
• The "Lock" (Prediction): "Will enforcing 'Equal Opportunity' (matching True Positive Rates) increase or decrease the overall throughput of your serving system?"
• The Workbench:
  • Sliders: Fairness Constraint Level (0-100%), Privacy Epsilon (\epsilon), Training Data Re-weighting.
  • Instruments: Fairness-Accuracy Pareto Plot. Shows the "Cost of Fairness" in terms of percentage accuracy points lost.
  • The 10-Iteration Rule: Students must find the exact "Fairness Threshold" that satisfies the Compliance Officer without dropping accuracy below the mission's "Utility Floor."
• Reflect: "Patterson asks: 'Is a 1% fairness gain worth a 10% increase in TFLOPS?' Use the RoC (Return on Compute) gauge to defend your decision."

Part 3: The Lifecycle Ledger (Synthesis - 15 Mins)

• Objective: Calculate the 3-year TCO and Carbon Footprint of the entire system.
• The "Lock" (Prediction): "Over a 3-year period, which will contribute more to the carbon footprint: Training the model once, or Serving it 1 million times?"
• The Workbench:
  • Interaction: Deployment Duration Slider (1mo -> 3yr). Energy Grid Mix Selector (Green vs. Coal).
  • The "Stakeholder" Challenge: The Sustainability Lead (or CFO) demands a "Lifecycle Audit." You must prove that using a Compressed Model (from Lab 10) saves more in carbon over 3 years than it cost in "Accuracy Loss" at launch.
• Reflect (The Ledger): "Defend your final 'Responsible Architecture.' Did you prioritize Carbon, Fairness, or Privacy? Justify your choice using the 3-year TCO projections."

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4. Visual Layout Specification

• Primary: DisparityDiscoveryChart (Disaggregated metrics across subgroups).
• Secondary: LifecycleTCORadar (Accuracy, Fairness, Carbon, Dollar Cost).
• Math Peek: Toggle for TCO = Capex + (P \cdot T \cdot Cost_{kwh}) and Carbon = Energy \cdot Intensity_{grid}.