Evaluation of historical buildings´ value based on the constraint lest square solution and definite algorithm

Evaluation of historical buildings´ value is one of the most important steps in the process of urban construction, and the coefficient of index system is the key of the evaluation process. This paper analyzes the observation equations in SEM and finds the least square relationship between the structural variables and observation variables. Adding a constraint with modular length to the structural variables, we obtain the constraint least square solution with modular length parameters (MCLS) for observation equations. The Coefficient index from MCLS is confirmed scientifically, which ensure the evaluation objective and qualitative.