How to Map Radio Reach: Signal Models Reveal Media Exposure During Mali's 2012 Coup

Insights from the Field

propagation models

media exposure

radio

Mali

signal strength

Using Electromagnetic Signal Propagation Models for Radio and Television Broadcasts: An Introduction was authored by Holger Kern and Charles Crabtree. It was published by Cambridge in Pol. An. in 2018.

🔎 What this note introduces

This note introduces electromagnetic signal propagation models as tools for estimating terrestrial radio and television signal strength across space. These models convert broadcast physics into spatial measures of how strong signals are at different locations.

📡 When this helps researchers

Signal propagation models are useful to social scientists trying to identify the effects of mass media broadcasts in cases such as:

When individual-level data on media exposure do not exist.
When media exposure is observed but is not exogenous.

🛠️ How the approach works

Uses electromagnetic signal propagation theory to produce spatial estimates of broadcast signal strength.
Produces a continuous, location-based measure of likely exposure to terrestrial radio and television broadcasts.

🗺️ Illustration: Mali's 2012 coup

An application is provided by creating a signal-strength measure for military-controlled radio stations during the 2012 coup in Mali. This example demonstrates how propagation models can generate exposure variables when direct measures are unavailable or endogenous.

⚖️ Why it matters

These modeled signal-strength measures offer a practical way for researchers to approximate media exposure and support causal inference about broadcast effects in settings lacking reliable individual exposure data.