Purpose of the Informal Segment Omission Module
This module explains the structural omission of informal residential segments from listing-based residential data in Johannesburg. Its purpose is to clarify why these segments are absent from formal observation and how their omission introduces interpretation boundaries at city, submarket, and district scales.
Informality and Non-Participation in Listing Systems
Informal residential segments operate outside standardized legal, marketing, and documentation frameworks. As a result, they do not consistently interact with formal listing platforms. This non-participation is structural rather than incidental and reflects a fundamental mismatch between informal residential practices and the requirements of publication-based systems.
Scale of Omission and Visibility Gaps
The omission of informal residential segments creates substantial visibility gaps within observable datasets. Entire residential environments may appear absent or lightly represented despite significant on-the-ground occupation. These gaps are not random; they are patterned according to tenure, form, and regulatory alignment.
Spatial Distortion Effects
Because informal residential segments are unevenly distributed across Johannesburg, their omission introduces spatial distortion. Districts or submarkets with higher concentrations of informal housing may appear less residentially active when viewed through formal listings. This distortion affects both localized readings and aggregated city-level interpretations.
Interaction With Other Structural Biases
The omission of informal segments interacts with other dataset biases, including selection bias and district overrepresentation. Together, these effects concentrate visibility in formally structured areas while systematically excluding large portions of the residential landscape from observation.
Interpretation Boundaries Created by Omission
The absence of informal residential segments establishes a hard boundary on what listing-based data can represent. Observed patterns should not be treated as approximations of total residential structure or distribution. This module reinforces the need to treat formal residential data as partial and to avoid extrapolation beyond its observable scope.