Independent variables in gross income models should be characterized as what?

Independent variables in gross income models are best characterized as property characteristics because these variables directly pertain to the attributes and features of the property that can influence its income-generating potential. This includes aspects such as size, location, age, condition, and type of property, all of which are critical in determining how much income a property can generate.

Property characteristics are essential for modeling because they provide the foundational data needed for assessment purposes. Understanding these traits allows assessors and appraisers to estimate a property's value and potential income accurately, making them the primary independent variables in gross income models.

While historical data, economic factors, and market trends may influence property income, they do not directly represent the intrinsic qualities of the property itself. Instead, they serve more as contextual elements that could impact the overall market but are not the core independent variables when specifically modeling gross income based on property characteristics.