Purpose of the Submarket Mapping Approach
This module explains the approach used to delineate residential submarkets within Johannesburg. Its purpose is to clarify how mapping choices are made, what constraints shape them, and why submarket boundaries are necessary for interpretation. The focus is methodological, not descriptive or evaluative.
Submarket Mapping as a Structuring Tool
Submarket mapping functions as a structuring tool that organizes heterogeneous residential environments into analytically manageable units. In Johannesburg, residential areas vary widely in urban form, housing typology, and listing participation. Mapping does not claim to resolve this complexity but provides a consistent framework for organizing observable data.
Inputs Used in Submarket Delineation
Submarkets are delineated using a combination of spatial continuity, commonly referenced district identifiers, and observable listing behavior. These inputs are selected to balance interpretability with practicality. The mapping approach prioritizes consistency across the city rather than precision at neighborhood scale.
Relationship to Listing-Based Visibility
Because the underlying dataset is listing-based, submarket boundaries are designed to group areas with broadly similar visibility mechanics. This reduces distortion that would arise from aggregating locations with fundamentally different publication patterns. Even so, submarkets remain subject to internal variation and uneven representation.
Boundary Approximation and Flexibility
Submarket boundaries are inherently approximate. They may not align with administrative borders, planning zones, or local perceptions. This approximation is a deliberate choice that acknowledges the limits of spatial labeling within listing platforms and avoids overconfidence in boundary precision.
Interpretation Limits of Submarket Maps
Submarket maps support comparative structure and scale control but do not eliminate bias or visibility gaps. They should be treated as interpretive aids rather than definitive representations of residential organization. This module establishes clear limits on how far mapped submarkets can be used without extrapolation.