The Models Of Quantitative Analysis In Real Estate Appraisal

Market Comparison Approach, Income Approach and Cost Approach are the three basic approaches in our nation's Real Estate Appraisal. In practice, there exists a common problem in the approaches, that is, the appraisal processes are all too subjective, depending on the experience of the real estate appraisers too much. This not only will make the result of appraising unreliable, but also may result in the moral risk, and then go against on the development of the whole real estate market. So it's in urgent necessary to set up models to make quantitative analysis in the appraisal process.In Market Comparison Approach, there isn't a fixed model in the process. The appraisers make the result depending on, in a great degree, their own experience, so, upon the same real estate, different appraisers may make out different results. By using Fuzzy Comprehensive Evaluation (FCE) in modifying the factors of comparable property, that is, set a FCE model in the process of Market Comparison Approach can not only weaken the function of appraisers' personal experience, but also put forward an objective result.In Income Approach, the process of getting the capitalization rate, a key factor in this approach, is too subjective, different appraisers may bring out different results according to their different experience. The small difference of capitalization rate may bring on the great difference of appraisal result. Using the Back-Propagation(BP) of Artificial Neural Net(ANN), putting in the main effect-factors of capitalization rate, and then the BP net will train thousands of times till the result go steady , that is the output of the net, capitalization rate.Cost approach puts up too subjectively by the confirmation of the objective-cost and the fresh degree of the subject property. Analyzing the method of confirming the objective-cost, it come to the conclusion that objective-cost should be calculated by the real-cost, but not the society average cost of the similar properties, and meanwhile, sets up a model for getting the objective-cost. The thesis uses Artificial Neural Net to confirm the fresh degree of the subject property, puts the 12 factors, which prescribed in 'Building Damage Grade Evaluation Standard'—a standard issued by the Construction Protection Part, that influence the building's fresh degree into this ANN model. Byrepeated training and studying, we can get the steady output——fresh degree of thesubject property.There is some difference in the applying condition of Market Comparison Approach, Income Approach and Cost Approach. How to choose the right method by different condition is also one of the key points that real estates appraisers must notice in the appraisal process.