Purpose of the Listing-Based Observation Method
This module explains the observation method used to capture residential information for Johannesburg through listings. Its purpose is to clarify how data enters the dataset, what is recorded, and why this method produces visibility signals rather than comprehensive residential representations. The focus is strictly methodological.
Observation Through Publication Events
Residential data is observed through discrete publication events on formal listing platforms. Each listing represents an instance of visibility generated when a residential unit is advertised. The observation method records these visibility events without assessing their duration, outcome, or underlying residential status.
Listings as Units of Observation
Within this method, listings—not properties or households—are the primary units of observation. A single residential unit may generate multiple listings over time due to relisting, marketing updates, or platform requirements. Conversely, many residential units may generate no listings at all and therefore remain unobserved.
Temporal Independence of Observations
Each listing observation is treated as temporally independent. The method does not assume continuity between appearances of similar listings, nor does it infer persistence or change in residential conditions. This approach prevents time-based inference from visibility patterns that are driven by rotation cycles.
Spatial Attribution Through Platform Labels
Listings are spatially attributed based on platform-provided location labels and categorization rules. These labels may not align precisely with administrative boundaries or on-the-ground spatial distinctions. The observation method records listings as they are labeled, preserving platform-defined spatial representation.
Interpretation Limits of the Observation Method
The listing-based observation method supports analysis of how residential offerings are published and circulated. It does not support inference about residential stock, occupancy, demand, or transaction outcomes. This module establishes the method as a visibility capture system with explicit interpretation limits.