This article, by Renmin University of China assistant professor Yao Yongling and graduate student Li Yao, describes a real estate management system developed for the city of Yancheng in the JiangSu Province in China. In order to accommodate the growth in housing and adapt to the increasingly complex ownership register situation, the Yancheng government officially proposed building a real estate GIS at the end of 2008, and completed construction of the system in November 2010. This system involves 420 square kilometers of land, 14 million residents and 26 million data records.
China is a country with a large population. As the Chinese real estate market has become increasingly active and prosperous, real estate management has played an increasingly important role in socio-economic development and the reform process. Faced with a huge amount of information, real estate management has become more complicated than ever with a variety of growing business demands. This article will give you a brief introduction to the status of real estate management systems based on GIS technology in China.
This case study/project was applied to Yancheng, China to create a real estate management system. Yancheng is located in eastern China and has a population of about 3.6 million. It is the administrative center for five county-level divisions, two districts and two cities, for a total population of about 8.1 million.
Yancheng has a long history of being the salt capital of China and an agricultural center. Recently, there has been an economic transition to high tech education and automobile manufacturing. Because of this transition, the government of China has been very active in real estate planning and the management of residential development to support continued growth.
Currently, most of the real estate registration departments in China have established property ownership registration information systems, cadastral management information systems, real estate surveying and mapping graphical information systems, and the real estate marketing information management system. But the following problems exist in current real estate management systems:
- Because there is no complete geospatial database, the existing systems are not connected.
- The various information systems are independent and can’t be integrated. So it is difficult to realize overall procedural and standardized management.
- There is no spatial management function in the existing real estate management systems, so statistical analysis cannot be conducted.
- There is no open social information system, so it is difficult to share information resources without a network function.
- The bottleneck problem of information service will always be a challenge. How to use the existing information management tools to improve public service and build a superior system? Establishing a real estate market warning forecast system is a task to be undertaken by the State Construction Ministry for China.
Why use GIS technology?
All real estate data have a common trait of geographic attributes, which are perfectly suited for management using GIS. Geocoding technology can organically combine spatial attributes, the natural attributes and social humanistic attributes of houses. The digital era of real estate information in China will happen with standardized networks and automated, modernizing real estate management systems.
- Introducing GIS systems to real estate can help with correct property registration and the use of real estate topographic maps. Using precise coordinates to define the location of real estate greatly improves the accuracy and reliability of real estate information. Management of that information will then become practical.
- A GIS with a standardized, geocodable database will help resolve ambiguous addressing.
- With a GIS application, it would be possible to conduct all sorts of statistical inquiries. With GIS, you can choose any geographic scope or define your theme to conduct statistical analysis. The government will also be able to improve decision making and conduct macro forecasting. For example, if you need statistical data about a potential demolition area, you could just select the scope you need on the map; the system can choose the area, households and other valid data accurately in a matter of seconds.
Key technology and details with the case
1. Establish uniform classification and geocoding standards.
Housing attributes and spatial attributes data are collected by real estate surveying and mapping work, while the social and cultural attribute data are acquired in real estate management. Setting up a good relationship between property surveying and mapping and property management, including uniform data classification and coding standards, is particularly important in setting up a real estate GIS.
Take Yancheng City in Jiangsu Province, for example. The geocoding is composed of city code, area code, street agency (township) code, house property division code, housing high number, room number and more. Once the geocode is established, it would not be changed with any city administrative division adjustments. It would accompany the house until it is demolished. This is the most powerful and useful function of GIS in the real estate industry.
2. Establish linkage between house geographical attribute information, the natural attribute information and social attribute information.
To link housing information to a property, we must establish a unique linkage keyword. Each house would have a unique geocode. Consequently, the geocode becomes the link keyword between housing spatial information data and attribute data.
In the case of Yancheng, when each house has a house geocode, that geocode will be the link keyword.Through this field, the attributes are associated together, forming a complete, accurate, comprehensive database for basic building information.
3. Establish a real estate geographic information database.
When GIS is applied to property management, it must mix modern mapping technology, large database technology, multimedia technology and computer network technology together to form a digital real estate system. It is obvious that speed and an effective real estate geographic information database are the basis of an advanced real estate GIS.
A real estate geographic information database consists of a spatial database and an attribute database. Spatial data mainly depend on field measurement, aerial remote sensing and attribute data acquisition using remote sensing interpretation and field survey, social investigation, examining the existing files, etc. Spatial data input methods include digital instruments, scanners, coordinate geometry and vector optimization of photographic measurement data. For attribute data, the input method is existing data conversion, manual assignment, etc.
A GIS-based real estate management system can provide a wide range of complete, accurate, detailed information to many other departments such as land management, planning, communications, gas, water conservancy, power and so on. Also, it can provide the government reliable basic data for decision making in urban construction. At the same time, real estate GIS can provide a good foundation for digital city construction.