- From: Bruce Bannerman <B.Bannerman@bom.gov.au>
- Date: Mon, 15 Jun 2015 00:26:54 +0000
- To: Frans Knibbe <frans.knibbe@geodan.nl>
- CC: SDW WG Public List <public-sdw-wg@w3.org>
- Message-ID: <D1A30AEC.1CE02%B.Bannerman@bom.gov.au>
Hello Frans, The use of metadata (I’ll qualify this as Discovery Metadata e.g. ISO 19115) and data being taken out of context is certainly part of the issue. Therefore I would not say ‘always traceable’ as per your response below. The discovery metadata (or similar) needs to be there in the first place. There is also a judgement that needs to be made based often on professional training, education and experience that needs to be used. It can take many years to build this knowledge base. To be honest I also see spatial professionals misusing spatial data from time to time. I apologise, I’m overcommitted at the moment and do not have the time to address this issue as appropriate. I’ll outline a few considerations and hope that our fellow spatial professionals on the list can add as appropriate: * Spatial data is typically an abstraction of a real world phenomena that has been prepared for a specific use case. * This data may, or may not be suitable for re-use for my purpose which may be at odds with the rationale used for the original use case. * For many use cases based on the same use case, people will find many ‘similar’ data sets to use as the basis for their use. How do they differentiate between them? * Which data sets can be considered to be ‘authoritative’? What makes them authoritative? * How was the spatial data set captured? Is it appropriate for my use case? * Is the data set maintained and subject to an appropriate QA process? * Is the data set a low precision dataset, e.g. digitised from 1:500,000 map where 1 millimetre of error represents 500 metres on the ground and my use case is high precision agriculture? * Does the data set use crisp polygons as an abstract representation of a phenomena that would be better portrayed as a continuous coverage? * What uncertainty is inherent in the data set (positional and attribute)? Does it affect my use case? * What algorithm should I use to process the data? E.g. * Should I use a 3 parameter polynomial or perhaps an NTv2 transformation on my high precision data set for my use case? * What am I actually getting when I run a spatial overlay function on crisp polygonal representation of a continuous phenomena? Is it meaningful? * Does my cartographic representation accurately portray an issue, or does it misrepresent the issue? For may use cases, the issues raised above may well be irrelevant. However, for may use cases the results of misuse could be life threatening or have significant ramifications. Bruce From: Frans Knibbe <frans.knibbe@geodan.nl<mailto:frans.knibbe@geodan.nl>> Date: Friday, 12 June 2015 02:08 To: Bruce Bannerman <B.Bannerman@bom.gov.au<mailto:B.Bannerman@bom.gov.au>> Cc: Jeremy Tandy <jeremy.tandy@gmail.com<mailto:jeremy.tandy@gmail.com>>, SDW WG Public List <public-sdw-wg@w3.org<mailto:public-sdw-wg@w3.org>> Subject: Re: BP Principles- more added [SEC=UNCLASSIFIED] Hello Bruce, Isn't misuse of spatial data always traceable to data somehow being taken out of context, or metadata being ignored or not being available? And isn't that true for any type of data? Regards, Frans 2015-06-11 13:59 GMT+02:00 Bruce Bannerman <B.Bannerman@bom.gov.au<mailto:B.Bannerman@bom.gov.au>>: Sorry Jeremy, I disagree with this ‘principle’. I have never bought the argument that spatial data is not ‘special’. There are many cases of domain data that is special where we would not throw it out there for anyone to use and misuse as they see fit. A good example is medical data. Most people would dream of opening up medical data for unfettered use by the uninformed. Some types of data demand domain knowledge to use appropriately and effectively. In many cases, spatial data is one of these. Do a search on ‘misuse of spatial data’ and you’ll get an appreciation of the issues. Bruce From: Jeremy Tandy <jeremy.tandy@gmail.com<mailto:jeremy.tandy@gmail.com>> Date: Thursday, 11 June 2015 21:19 To: SDW WG Public List <public-sdw-wg@w3.org<mailto:public-sdw-wg@w3.org>> Subject: BP Principles- more added Resent-From: <public-sdw-wg@w3.org<mailto:public-sdw-wg@w3.org>> Resent-Date: Thursday, 11 June 2015 21:20 * The Best Practices must be actionable by web application developers who just (!) want to use spatial data not become GIS experts; spatial data is just one facet of the information space they work with, so let's not make it special by requiring up front knowledge. -- Frans Knibbe Geodan President Kennedylaan 1 1079 MB Amsterdam (NL) T +31 (0)20 - 5711 347 E frans.knibbe@geodan.nl<mailto:frans.knibbe@geodan.nl> www.geodan.nl<http://www.geodan.nl> disclaimer<http://www.geodan.nl/disclaimer>
Received on Monday, 15 June 2015 00:27:28 UTC