DCW Users: A Call For Response

[Digital Chart of the World]

Greetings, 

The United Nations Environment Program's Global Resource Information Database
in Arendal, Norway (UNEP/GRID-Arendal) along with the Department of Surveying 
at the Agricultural University of Norway have initiated a project to examine 
data quality issues for spatial databases. Specifically, these issues will be
examined for one of the world's most comprehensive and detailed GIS databases,
the 1:1 million Digital Chart of the World (DCW).  One of our tasks is to review
and summarize present use, experiences, and quality assessments that have
been carried out on the DCW and its base map material. In support of
this effort we are asking the GIS and Remote Sensing community to provide
some information on their experiences with the DCW. To encourage users
to respond, we have provided a short questionnaire for DCW users 
to complete.

Our project will be completed in August, 1995, at which time
we will make our report available to the public. Also, we will forward a
copy of our report through the post to each individual that submits information
on their experiences with DCW data. More details on our project are provided 
after the questionnaire. Thanks in advance for your time and efforts.  
(Christopher G. Smith)
 
PLEASE REPOND DIRECTLY TO: dcw at grida.no 

QUESTIONS:

1. Please provide your name, address, phone, and email.

2. Briefly describe your particular use of the DCW data.

3. Which geographic region(s) do you use DCW data?

4. Which layer(s) of the DCW are you using? 

5. Which software package do you use to work with the DCW data?

6. Did you experience problems with the quality of the data? (Y/N)
   If yes, briefly describe your problems. 

7. Are you willing to provide further information concerning the quality
   of these data? (Y/N)   

PROJECT TITLE: 
Issues of Error, Quality, and Integrity of Digital Geographic 
Data: The Case of the Digital Chart of the World

RESPONSIBLE PERSONNEL:  
Langaas, S.(1), Tveite, H.(2), Baxendale, H.J.(3), and Smith, C.G.(3)
(1) UNEP/GRID-Arendal
    c/o Dept. of Ecology, Stockholm University, S-10691 Stockholm, Sweden.
(2) Dept. of Surveying (ILM), Agricultural University of Norway (NLH), 
    P.O. Box 5034, N-1432 As, Norway.
(3) UNEP/GRID-Arendal
    Longum Park, P.O. Box 1602, Myrene, N-4801, Arendal, Norway.
    Phone: +47 37 03 56 50 Fax: +47 37 03 50 50

PROJECT SUMMARY:
This project will examine the concepts of accuracy, error and integrity 
as applied to spatial databases, and specifically relate this examination to 
the world's most comprehensive and detailed 'public domain' GIS database, the 
Digital Chart of the World (DCW) with nominal scale of 1:1million. 

Four interrelated tasks will be accomplished during the study:
(1) To theoretically examine the issues of accuracy and integrity of spatial 
    databases and recommend assessment techniques. 
(2) To provide a comprehensive summary of the documentation that describes 
    the lineage of the data set, covering the entire process from image 
    interpretation to final CD-ROM structuring.
(3) To review and summarise present use, experiences, and quality 
    assessments that have been carried out on the DCW and its base map 
    material.
(4) To quantitatively perform quality assessments of the DCW on selected 
    regions using other georeferenced data sets with higher known accuracy. 

The anticipated beneficiaries of the project will be:
(1) The GIS community, both data producers and users, both practitioners and 
    academicians, concerned with quality aspects of georeferenced data. 
(2) All users of DCW data.


+------------------------------------------+----------------------+
| Christopher G. Smith [smith at grida.no]    | +---+---+---+---+    |
| Systems Analyst                          | | G | R | I | D |    |      
| GRID - ARENDAL                           | +---+---+---+---+    |
| P.O Box 1602, Myrene                     | UNEP/GRID            |
| N-4801 Arendal, Norway                   | Global Resource      |
| Phone: +47-370-35650; Fax: +47-370-35050 | Information Database |   
+------------------------------------------+----------------------+