Many competition cases require geographic analysis — defining relevant markets, identifying competitive constraints, and assessing the impact of structural changes across locations. While established analytical frameworks remain central, the toolkit is expanding: more sophisticated measures of competitive proximity, sensitivity testing across multiple specifications, and interactive visualisation are increasingly part of the picture. This article presents a series of tools developed by RBB Economics, each illustrating a different application.
In practice, tools are often tailored to the specific case — calibrated to the relevant methodology, incorporating actual transaction and location data, and designed to support analysis from initial screening through to remedy design. The examples below use fictional data to illustrate the underlying capabilities.
Best experienced on a desktop or larger screen. Each map can be expanded for a full-screen view, and a link to a combined full-screen version of all topics is available at the end of the article.
Catchment area analysis
How far do customers travel, and does the methodology matter?
A fundamental step in local competition analysis is understanding the geographic reach of each supplier — how far customers travel to reach it, or how far it travels to serve them. In practice, this is often assessed through catchment areas: zones around each location constructed from observed data, straight-line distances, drivetimes, or administrative boundaries. The approach adopted can materially affect which competitors are captured and how the competitive landscape is assessed.
Market share estimation
How sensitive are shares to the definition of the local market?
Once a local market is defined, the standard approach counts all competitors within that market and may compute shares in several ways — by store counts, revenue, or selling space, and under different assumptions about catchment size and travel mode. Small changes in these parameters can shift shares substantially, altering the competitive assessment. Understanding the sensitivity of results to these choices is key to establishing how robust the findings are.
Competitive overlap analysis
Moving beyond binary in-or-out catchment definitions
The standard approach draws a hard boundary between competitors inside and outside the catchment area. In reality, competitors just beyond the boundary may still pose a meaningful constraint. More sophisticated approaches such as overlap-weighted shares refine this by measuring how much each competitor’s customer base overlaps with the focal store’s, producing a more nuanced picture of local competition.
Large-scale competitive screening
From national overview to store-level detail
Mergers involving hundreds or thousands of locations across a country require analysis that can operate at scale without losing sight of local detail. The challenge is navigating between a national overview and the store-level picture that drives the competitive assessment. Efficient screening and the ability to zoom into any local market are essential.
Divestment simulation
Finding the package that resolves concerns at minimum cost
Where a merger raises concerns at specific locations, divestment of individual sites may be required. The question is which combination resolves all local concerns while minimising the commercial cost to the merging parties, given that divesting one site changes the assessment at neighbouring locations.
Vertical merger and foreclosure analysis
Mapping upstream and downstream dependencies
In vertical mergers, the concern is not direct overlap between competitors but may be whether the merged entity could foreclose rivals — by withholding inputs or refusing to purchase from independent suppliers. The geographic dimension matters because supply relationships may be distance-dependent: a mill’s vulnerability depends on which groves are nearby and who controls them. Mapping these dependencies reveals where foreclosure risks are concentrated.
For the best viewing experience, the full interactive presentation combines all six topics in a single navigable map.
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