The Importance of Land Surveying Equipment Calibration
The Land Use Change Assessment Group of the NYCHP utilizes the SLEUTH land use model to assess historical and predict future land use change in the study region.
What is SLEUTH?
“The Urban Growth Model (UGM) is a C program running under UNIX that uses the standard gnu C compiler (gcc) and may be executed in parallel. It can be formatted for any other standard C compiler. Some minor changes in the code might be necessary for execution in new environments. In order to implement the model a good understanding of C programming is expected.
The land cover deltatron model (LCD) is included within the code and will be called and driven by the UGM. The LCD is tightly coupled with the urban code, but the UGM can run independently of it. Together, these coupled models are referred to as SLEUTH. The name SLEUTH was derived from the simple image input requirements of the models: Slope, Land cover, Exclusion, Urbanization, Transportation, andHillshade.” – (source)
The SLEUTH model was developed by Dr. Keith C. Clarke at UC-Santa Barbara and integrates 2 sub-models, the Urban Growth Model (UGM) and the Deltatron Land Use/Land Cover Model (DLM). The disadvantage of SLEUTH is that it currently only defines built-up land and does not model intra-urban categories.
A main data source for SLEUTH is the USGS Urban Dynamics Data, which was received in collaboration with Roger Barlow (USGS), Ann-Margaret Esnard (Cornell University), Janet Tilley (USGS), and Dan Sechrist (USGS). The dataset was developed for the New York metropolitan area and includes data at three resolutions: 10-acre, 1-acre, and 35-meter. 70-meter data was derived from the 35-meter data.
This all poses two very interesting questions:
How accurate is SLEUTH?
Can SLEUTH be use to predict future New York state land value?
The answer to the first question lies on the shoulders of the fact that calibrating a land surface model of varying complexity is no easy task. PIE (Formerly Altek) are a team of expert engineers to specialize in calibration. They believe it all starts with calibrating measurement equipment otherwise the data received from the measurements will be inaccurate. PIE has sold calibrating equipment to land surveyer companies in the past and their clients have always stressed the importance of properly calibrated surveying equipment.
As for the second question…
Speculating on anything creates a margin of error but SLEUTH has been making headway in the world of land surveying and speculating. There is only one disadvantage: “It (SLEUTH) currently only defines built-up land and does not model intra-urban categories.”
To real estate investors, who are looking to maximize the ROI of their speculative efforts, a computer program using data from properly calibrated measurement equipment can give them the edge they need to “place the right bet.”