Abstract: A method and machine-readable media are provided for estimating property values. An exemplary method includes obtaining a first estimate of a property from a first property valuation database, the first estimate exhibiting price tier effect bias. The method further includes deriving a price tier effect adjustment factor based on a price tier associated with the property and purchase transaction data. The method further includes adjusting the first estimate to reduce the price tier effect bias using price tier effect adjustment factor, thereby providing a second estimate having reduced price tier effect bias.

Abstract: A method and system are provided removing systematic bias from property value predictions obtained using automated property valuation models. The systematic bias is removed by deriving monthly adjustment factors that are location-specific. The monthly adjustment factors are obtained by comparing newly obtained purchase transaction data to model-generated valuations of properties in a base valuation database. The newly obtained purchase transactions may be obtained from newly obtained data on recently completed purchase transactions and loan application data on future purchase transactions. The monthly adjustment factors are applied to the property valuations in the base valuation database to obtain adjusted property values having reduced bias and thus improved accuracy.