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The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B4. Beijing 2008 
net income is the gross income less the cost of overheads, such 
as depreciation of the building stock and its maintenance and 
upkeep. It is equivalent to a national rent and must be 
discounted at an appropriate rate. The valuer's problem is to 
determine the net benefits that should come from the land by 
comparison with similar properties; and then to determine the 
market discount rate by analyzing recent sales of similar assets. 
2.3 Cost Method 
This is also known as the contractor's method or the quantity 
survey approach. It assumes that the costs of replacement, less 
appropriate depreciation, are equal to the value. The problem is 
to assemble suitable cost data, including the cost of the site, and 
to estimate depreciation rates. The method is particularly useful 
for insurance purposes, where the cost of site clearance may be 
added to cover the possibility of a building being destroyed by 
fire, and for valuing new constructions. 
Some linear features could not be clearly identified without 
a special experience. 
3.2.2 Georeferencing the Satellite Image 
The process of assigning coordinates to points on the image of 
known locations easily distinguished on terrain was carried out 
from Ground to Image. These well-identified points on the 
image were determined on the ground by means of handheld 
GPS (GeoExplora XT) with the basic technical performances of 
submeter accuracy, 12 channels, 1 Hz position update rate and 
30seconds typical time for initial fixation [2]. 
A total of 8 well distributed points were measured in the 
vicinity. In choosing points preference was given to stable 
visible structures in order to setup a network of points that could 
be easily located even in later series of data collection. Making 
use of 4 Ground Control Points (GCPs) and 4 check points (CPs) 
in correspondence to the best fit of the entire image gave the 
following interpretation (Fig. 1). 
3. PROBLEM SOLUTION 
Projection information used in georeferencing; 
Integrated Geographical Buffering System (IGBS) is the most 
effective and easy to comprehend; It provides quick and cheap 
technological platform on which to base such an analysis and an 
initial stage is the spatial representation of property information 
in the form of value maps. Capabilities of Geographical 
Information System not only facilitate the organization and 
management of geographic data, but they also enable 
researchers to take full advantage of location information 
contained in these databases to support the application of spatial 
statistical and spatial econometric tools[ 1 ]. 
Due to the complexity of land valuation process, providing 
property owners with an easy understood explanation of how 
their property has been valued is a continual challenge for 
planners and assessors. The Integrated Geographical Buffering 
System based on GIS and GPS fulfills the above requirements 
executing all these complex tasks. Thus, using Buffering 
modules, a visual value model and required valuation maps can 
be created. 
3.1 Materials and Methods 
Projection Type 
Longitude of central meridian 
Spheroid Name 
Latitude of origin of projection 
Datum Name 
False easting 
Scale factor at central meridian 
False nothing 
Transverse Mercator 
80:46:18.160 E 
Everest 
07:00:01.725 N 
Everest 
200Km 
0.99992384 
200Km 
3.2.3 Parcel Boundary Identification and Weight Assigning 
Enlarged satellite base image was more useful for tracing off 
parcel boundaries by interactive digitizing (polygon mode) in 
which the results of each operation were immediately shown on 
a graphic screen, all the visible and identifiable boundaries out 
of fixed (specific) and general (uncertain and variable) 
boundaries could be digitized on desktop satellite image. And 
the other ambiguous (uncertain and unsettled) boundaries could 
be re-determined by directly through field verifications and 
indirectly from other sources such as existing data records in 
land settlement office, land registration office, planning office 
etc. along with a long visual inspection. 
3.1.1 Study Area 
The study area was 4 (square kilometers) ground area in 
Gampola region in Kandy District in Central Province of Sri 
Lanka where the land is not homogeneous but full of varieties, 
which consists of a land cover of land parcels, buildings, 
transportation (roads/railways), vegetations/cultivations and 
other infrastructures. 
3.2 Activities 
3.2.1 Preliminary Investigation 
Arc View GIS Version 3.1 was used for different purposes 
during test phase. Before initializing the test phase high 
resolution satellite background imagery which covers the study 
area was preliminarily investigated in detail and realized 
following findings. 
Storage size of the satellite image in tiff type was around 4 
MB. 
Study area was with in a single satellite image. 
Linear features such as parcel boundaries, road edges could 
be identified. 
Using raster based GIS, unit land value was defined as a 
weighted average of a number of factors affect valuations; 
Land-use category (residential, industrial, commercial, 
agricultural etc.) 
Site/location 
Amenities enjoyed 
Quality of infrastructure 
Building Size 
Design 
Shape 
Construction quality 
Construction materials 
Other building features 
Age/extent of depreciation 
Population (No. in house hold) 
Land ownership (Freehold, Leasehold)