XXV FIG Congress, Kuala Lumpur, Malaysia TS02E-3D Using 3D Geographic Information System to Improve Sales Comparison Approach for Real Estate Valuation Haicong Yu Center for Assessment and Development of Real Estate, Shenzhen June 17 th 2014 Outline Part 1 Introduction Part 2 Solution Part 3 Case study Part 4 Conclution
Introduction Sales Comparison Approach Widely adopted approach for real estate valuation For certain types of properties Expert knowledge Data quantity and quality requirements Field survey work Introduction Challenges: Data Inadequate (real time update) Data integrity and data fusion (multi-subject, multi-source, multi-scale, multi-structure ) Challenges: Technology Vulnerable in analysis, lack of spatial analysis Subject to personal judgment Challenges: Informatization Manual work Lack of valuation standardization & unified platform
Introduction New technologies Computer Science ( CS ) Geographic Information System ( GIS) Database Management System ( DBMS) Virtual Reality ( VR) Internet/Intranet Introduction Idea CS Automate Valuation Model Valuation GIS VR 3D GIS Valuation Model DBMS Valuation Database Internet/Intranet Online working
Property Direct sales data comparable set sales set Selected comparable sales Establishing comparison basis Conditions of sale adjustment Time adjustment factors adjustment Individual factors adjustment Land use life adjustment Sales comparison value Subject property value Direct comparable sales selection model Property sales data set Subject property Buffer analysis Expanding search area Parallel analysis No Comparable sales number n: 5<n<=10 No Add self-defined sales records Yes Direct comparable sales set
Property sales data set Direct comparable sales set Establishing comparison basis Conditions of sale adjustment Time adjustment factors adjustment Individual factors adjustment Land use life adjustment Sales comparison value analysis based on Spatial Analysis Subject property value planning Plot ratio analysis factors prosperity Transportation convenience Landscape Environmental condition Fundamental infrastructure Individual factors Project scale Ages Related service facility Rest land use term Public facility conditions Decoration
analysis Directly adopt analysis results, or through simple transformation; Utilize Likert scale; Utilize comprehensive measurement index system, and scores the results. analysis factors Data involved planning prosperity Transportation convenience Landscape Environmental condition Fundamental infrastructure Public facility conditions Urban master planning and detailed planning documents, maps, planning data Business area data Bus stop, subway station, MRT, airport, train station, port and pier, and road network data with carriage information Ocean, lake, mountain, green, forest park and golf course data Environmental monitoring data, road network, traffic, pollution monitoring data, waste yard, incineration plant, power station, high-voltage power lines, and 3D buildings and so on Under ground water pipe, electricity line, gas pipe, communications, cable, internet, wireless local area network and so on Point of interests in all category Analysis methods Spatial query, spatial overlay Spatial measurement, network analysis Spatial measurement, network analysis, road network accessibility analysis, spatial statistics Visibility analysis, spatial measurement, spatial statistics Spatial query, noise propagation analysis, pollutants diffusion analysis, visibility analysis, solar shadow analysis, spatial statistics Spatial query, spatial statistics Spatial query, spatial statistics
analysis Performance matrix Reference column A 0 0 1 2 1 10 11 12 1n 2 20 22 22 2n m m0 m1 m2 mn Dimensionless treatment q A A A... A B q q q... q B q q q... q.................. B q q q... q ' ij n = q q ij i0 analysis q q... q q q q............ q q... q δ1 δ2... δn ' ' ' 11 12 1n ' ' '... 21 22 2n ' ' ' m1 m2 mn j m δ = q i= 1 ' ij
analysis ' ' ' q11 q... 12 q 1n ' ' ' m ' q21 q... 22 q2n δ j = qij i= 1............ ' ' ' q... m1 qm2 q mn δ δ δ = δ 1 1 2... n 0 < p < q < r <... < l i i Property sales data set Direct comparable sales set analysis B1 q10 q11 q12 q13 B2 q20 q21 q22 q23............... Bm qm0 qm 1 qm2 qm3 p1 p2 p3 δ1 p1 δ2 p2 δ3 p3 1 Sales comparison value Subject property value P = δi p 3 i
Real Estate Valuation Database Valuation essential data Real estate sales records data real estate attribute data & real estate price data Valuation parameters data parameters, coefficients, indices and interest rates Spatial data Land data Building data Road data Multilevel administration zone Remote sensing image Topographic map Land benchmark price Point of interests Real Estate Valuation Database Valuation thematic data Building attribute: stores name, structure, corresponding cost and pictures Structures & fixtures attribute: stores name, type, engineering calculation rules, corresponding price and pictures Plants & trees: records different species, name, pricing and pictures Decoration: stores name, engineering calculation rules, and corresponding prices and pictures Construction cost: records construction cost and related technical and economic indicators
Case Study Valuation Functions 1.Compariable sales selection 2.Parameters Setting 3.Valuation Report Generation 4.Valuation Results Comparison Case Study Spatial Analysis 1.Project Locate 2.Query 4.Factor Analysis 3.Sales Display 5.Sales Comparison Transportation convenience Environmental condition ba prosperity Landscape Environmental condition Fundamental infrastructure planning Public facility condition 20
Conclusions Real estate relevant spatial and non-spatial data can be well collected and managed for valuation through GIS database A 3D GIS sales comparison approach improved the traditional sales comparison approach in many ways The application of 3DGISSPV system improves the working efficiency and the valuation accuracy 21