A matching method for land valuation

Abstract

One approach to land valuation, particularly used by accessors, is to base price estimates of target properties on comparable properties that recently sold. These properties are chosen to be close matches of the target unit and their transaction prices are used to predict the market price of the target unit. But the choice of comparables is typically not consistent and transparent. In this study, a systematic analytical procedure for choosing comparables that is easy to implement is developed. A hedonic regression using these comparables is then run and the predicted value of the target unit is the assessed value. One of the advantages of this procedure is that it should be straightforward for assessors and public finance officials to use and understand and easy to explain to residents.

This approach is used to estimate land value as well as market prices (that includes the value of the structure) for single family residential properties using data from Maricopa County Arizona from 2007-2018. The best estimators obtain a median prediction accuracy error of 10% and more than 60% of these predictions have a prediction accuracy error within 10% for later years in the sample. These are within the bounds obtained by Zillow for 666 U.S. counties. Market prices are disaggregated into structure, lot, and neighborhood values. On average, these three components make up approximately 30%, 20%, and 50% of total average price. This provides for a nice “rule of thumb” for decomposing the market average property value into these three components; two of which relate to land value.