個別估價與大量估價之準確性分析The Accuracy of Valuation: A Comparison of Appraisers and Mass Appraisal

近來在大量估價模型發展的態勢下，引起不動產估價產業不小的衝擊，面對這波衝擊，有人稱之為「估價革命」。過去相關文獻中，個別估價多集中在估價行為或估價技術的改進；大量估價多著墨於運用各種數量方法建立大量估價模型，但少有兩者的比較研究。本文有鑑於兩者特性迥然不同，難以進行全面性比較，故選擇準確性作為衡量標準。以尊重台灣目前發展現況為前提，分別設計個別估價與大量估價的操作模式，藉由相同的勘估標的，分別取得各自的估計值，進行命中率、評估比值與絕對百分比誤差等準確性指標的差異性分析。實證結果顯示，整體而言，兩者的準確性並不具有統計上的顯著差異，但更細微的檢視，仍有分配上的差異。
關鍵詞：準確性、個別估價、大量估價

The rapid development of mass appraisal techniques has had a huge impact, referred to as the valuation revolution, on appraisers. A large literature has developed in relation to establishing a mass appraisal model, but there have been few studies that have compared the valuations by appraisers for the same objects as well as mass appraisals. This article aims to examine the accuracy of such techniques by means of the hit ratio, assessment ratio and MAPE. The results broadly indicate that there are no statistically significant differences across these measures, but that there is a little variance in accuracy in. terms of price distribution.
Key words: accuracy of valuation, appraiser, mass appraisal, AVM