|
|
|
Lessons Learned
|
The database design: The key to success
- Allow the conversion companies sufficient time to respond to an RFP. As the end of a calendar
year approaches, conversion companies anticipate with dread the flood of RFP’s that suddenly appear
(often requiring an almost instant response) for projects that may often cost hundreds of thousands of
dollars to produce. Realizing that our clients are usually constrained by budgets which are often not
released until close to year-end, and that optimal flying times for many areas of the country occur within
a matter of months after year-end, the solution to this dilemma can be difficult. However, since the
development of a quality data conversion specification should require at a minimum three months time
(Lerner and DiSera, 1996), it seems reasonable to allow at least half that time for responses to be
received by data conversion vendors. Six to eight weeks will allow plenty of time for the next two points
listed below to be fully realized.
- A11owtime for questions from conversion providers to formally become part of an amended RFP
Each interested company will make different assumptions about exactly what the requester wants, and
these written questions will prove to be a very usefi.d learning exercise to the end-user party. In addition,
these questions and the accompanying answers keep all parties using the same knowledge base in
discussions. As with the Request for Information (RFI) advocated by Reid (Reid, 1992), these questions
will ultimately allow for more accurate price quotes once the project is better understood.
- Allow bidders access and time to inspect all source documents. As with the general questions
about the RFP and accompanying database design document, this exercise helps everyone understand the
assumptions being made by the other parties to the GIS implementation. By this time, of course, the
end-users should be thoroughly familiar with their source documents. The conversion companies,
however, are not, and can usually provide valuable insight into numerous issues via their source
inspections. Samples of these sources can even be included in the RFP if not cost-prohibitive, and are
~ways appreciated. It is particularly important to see all digital sources that need to be integrated into
the final database in order to check for completeness, accuracy and formatting.
- Retain the GIS consultant until a data provider is selected and all conversion issues are resolved.
Ideally, the GIS consultants’ and data conversion companies’ periods of time spent working on a GIS
implementation should overlap by several months. Often, however, this is not the case as the consultant
is paid in full once the RFP is issued or the conversion company is selected. This leaves the end-user to
deal with all the issues detailed above alone, usually when they are already overworked. By retaining the
consultant until the pilot is complete and full production is underway, the end-user has someone to turn
to not only when complicated issues arise, but in case it becomes obvious that the consultant has not
performed their job properly in some way in the education of their client.
- Include detailed footnotes in the database design specifying sources and selection criteria.
Table 1 spells out many of the issues faced by data conversion vendors for just one theme commonly
found in most planimetric mapping GIS implementations. One would think hydrography would be one
of the easier themes to understand. However, as the table shows, numerous issues arise concerning
definitions, digitizing procedures, minimum and maximum dimensions for data to be captured, etc. This
information is extremely important not only once data capture is set to begin, but at the very beginning
stages of a GIS project when both end-users and data conversion providers are trying to figure out
exactly what is needed. The ultimate conversion cost can be affected dramatically by the precise
definitions given in the database design. Take as an example the way in which the hydrography theme
could be affected in a state such as Florida. If the end-user only needs to know where canals of greater
than 20 feet in width or swamps larger than 200 acres are located, this detail should be present in the
RFP. Otherwise the data conversion companies will assume all of these features are required and the bid
price will be adjusted upward accordingly.
Conclusions
The process of designing and writing a database design documen~ or data conversion specification, is a
time consuming but extremely important procedure in the overall scheme of a GIS implementation. Any
corners cut during this process will undoubtedly make themselves felt later as the issues ignored early on
come back to haunt the end-user of the GIS. Working together with both the GIS consultant and the data
conversion company selected, most of the pitfalls known through years of experience can be avoided.
Since most end-user clients are new to the GIS community, the primary responsibility for their education
and for the avoidance of major problems lies with the selected consultant. Once a conversion company
is selected, they too must share an equal role in taking responsibility for the overall success of a project.
However, there must be a solid commitment on the part of the end-user to put in all of the work
necessary in order to omit as much of the uncertainty and ambiguity about the stated needs and goals of
the GIS. Data conversion companies and GIS consultants do an excellent job when they know exactly
what is required of them. With all parties working together, the end result will always be a positive one.
References
- Hawkes, A.G.D., 1994, “The Conversion Specification: Foundation for Success”, JYocee-Conf_
e XVII, pp. 662-667.
- Lerner, N. and DiSera, D., 1996, “Cost Effective Database Design: What Every Manager Should
Know”, GIS/J .1S ’96: Annual conference and Exposition Proceedings . . , pp. 1034-1049.
- Meyers, T.F.., 1994, “Managing Data Conversion Costs”, mceedings: AM/FM
, pp. 726-735.
- Reid, W.B., 1992, “How to Select the Best Conversion Contractor for Your Project”, m
Proceeclings. VOhundI , pp.129-138.
- Thorpe, A., 1995, “Keys to Successful Water Conversion”, lJRISA Proceeding. Vol . d, pp.322-
|
|
|
|
