Arthur Chapman sent me some good comments regarding Datums etc.<div><br></div><div>The discussion made me realize that there may be a need for two types of formats. One for the providers and a second one that is output by the harvesting service.</div>


<div><br></div><div>This is because the needs and abilities of the data providers are different than the needs and abilities of those who would like to consume the data.</div><div><br></div><div>Consumers, who analyze and map the data, would like something that is easy to process, standardized and as as error free as as possible.</div>


<div><br>It could work in the following way.  </div><div><br></div><div>Data harvesters, like GBIF, collect the records. Run them through cleaning algorithms that check attributes including that the lat and long actually match the location described.</div>


<div><br></div><div>These harvesters would then expose this cleaned data via XML and RDF with tags that flag possible inconsistencies. The harvesters would also add a field for the lat and long in WGS84 if the original record contains a valid Datum. Those records without a Datum would still be exposed but the added geo:latitude and geo:longitude fields would be empty.</div>


<div><br></div><div>I can imagine that that data uploaded to GBIF and other harvester services will be replete with typo&#39;s and inconsistencies that will frustrate people trying to analyze or simply map the data, the harvester services could add value by minimizing these frustrations.</div>

<div><br></div><div>Originally, it seemed that a global service should standardize on a global Datum like WGS84. After all, we have standardized on meters? However, after discussing this with Arthur, I realize that this is not possible for a number of reasons. That said, I think the data would be much more valuable and less likely to be misinterpreted if if a version of it was available in WGS84. This solution would eventually encourage data providers to understand what a Datum is and include it in their data. It would also help solve a number of other data integration problems.</div>

<div><br></div><div>Respectfully,</div><div><br></div><div>Pete</div>
<div><br></div><div><br></div><div>---------------------------------------------------------------<br>Pete DeVries<br>Department of Entomology<br>University of Wisconsin - Madison<br>445 Russell Laboratories<br>1630 Linden Drive<br>


Madison, WI 53706<br>------------------------------------------------------------<br>
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