Tiers Explorer Guide

Tiers Explorer Guide

A comprehensive breakdown of the 6-tier Lexicographic Constrained Optimization (LCO) hierarchy.

What is Lexicographic Constrained Optimization?

LCO solves multiple competing objectives in strict priority order. Instead of blending all objectives into a single weighted sum (which requires arbitrary trade-off decisions), LCO optimizes each tier sequentially: once a tier's objective is achieved, its optimal value is frozen as a hard floor constraint for every subsequent tier. Lower tiers can only optimize within what higher tiers have already guaranteed.

Priority Order

Ethics → Revenue → Risk → Operations → Workforce → Sustainability

Floor Locking

Each tier's result Z_k* becomes Z_k* − ε_k, a binding lower bound for all tiers below it.

Tolerance (ε)

ε controls how strictly the floor is enforced. ε = 0 means no loss allowed vs. the tier's optimal.

How to Use the Tiers Explorer

  1. Click any tier in the left sidebar to view its detail panel on the right.
  2. Read the objective, constraints, and paper example for that tier.
  3. Click "Optimize & Lock Floor" to simulate floor-locking and automatically advance to the next tier.
  4. Repeat until all 6 tiers are locked — this mirrors the full LCO sequential solve.

The 6 Tiers — Click to Expand

Floor Locked → Next Tier

Floor Locked → Next Tier

Floor Locked → Next Tier

Floor Locked → Next Tier

Floor Locked → Next Tier

Tier Summary — At a Glance

TierNameTypePaper Improvement
L1Feasibility / EthicsHard ConstraintsAll VIP & ADA guaranteed
L2Revenue / MarginMaximizeZ₂* = $1,847 (revenue ceiling)
L3Risk / OverbookingMinimize−55% slack, 98.2% revenue retained
L4OperationsMinimize−14% housekeeping turns
L5Workforce FairnessMinimize−25% overtime shift-hours
L6SustainabilityMinimize−9% energy proxy
Based on the 10×5 instance from Appendix A of the LCO paper • Valamontes, 2026