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Agent-Based Modeling for Supply Chains���Data Science for Modeling Workshop�Addis Ababa, Ethiopia�February 5, 2026���Sachiko Ozawa�Professor�Practice Advancement & Clinical Education�UNC Eshelman School of Pharmacy �Ozawa@unc.edu��

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This session’s objectives

  • Examine existing supply chain models

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  • Start to sketch a supply chain model

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Medicine Supply Chain Models

Model Examples

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Systematic Review of Medicine Supply Chain Models

System dynamics was the most applied approach at 42% (n = 13)

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6% (n = 2) employed a hybrid simulation approach.

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Systems Dynamics Supply Chain Model

Case Overview

  • SD model built for second‑line TB drugs in South Africa using historical data.
  • Modeled ordering, delivery, stock levels, and service reliability.

Key Levers Simulated

  • Order frequency/size.
  • Safety stock levels.
  • Lead‑time changes.

Outcomes

  • Identified inventory management policies to reduce stockouts and costs.

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https://academic.oup.com/heapol/article/32/8/1127/3852233

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SD Model

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SD Model

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SD Model

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SD Model

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Agent-Based Model + Discrete Event Simulation

Improving medicine supply and availability using simulation: a case study of Uganda

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ABM-DES Model

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ABM-DES Model

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ABM-DES Model

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ABM-DES Model

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Hybrid Models

Hybrid Systems-Dynamics and Agent-Based Models

  • Tools like AnyLogic support SD, ABM, and discrete event integration.
  • Hybrid models combine strengths: ABM handles heterogeneous actors; SD handles aggregate feedback dynamics.

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Why Hybrid Is Valuable

  • Captures macro trends and individual decisions.
  • Better for complex supply chains (e.g., multi‑tier networks).

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Hybrid Model

A Simulation Approach for the Design of More Sustainable and Resilient Supply Chains in the Pharmaceutical Industry

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Hybrid Model

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Hybrid model

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Hybrid model

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Hybrid model

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Sketch A Supply Chain Model

Group Work

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Agent-Based Medicine Supply Chain Model

Agents

Rules

Environment

Exercise: You are modeling the essential medicines supply chain in your country. The goal of the model is to understand stockouts and wastage under different ordering and distribution policies.

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Identify the following:

Agent Attributes

Interactions

Outcomes & Policies

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Worksheet

Goal: Develop an agent-based model of the essential medicines supply chain in your country to understand stockouts and wastage under different ordering and distribution policies.

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  1. Who will be your agents, and what characteristics will they have?

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  • What are the environments (locations) you want to have in the supply chain model?

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  • How will the agents engage in the environment ? What rules will you set on how they behave?

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  • What ordering and distribution policies would you like to test in the model?

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Any Questions?

ozawa@unc.edu

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