Harvest

This week we are exploring harvesting metadata across collections with the goal of forming useful strong federated searches. I won't go into the difficulties of my own data harvesting experiences except to say; thank goodness it wasn't the corn crop or we'd all starve. That isn't said to diminish the usefulness of harvesting metadata and the concept of federated searches but only to state that I had trouble with the PKP harvester software itself. A lot of trouble.

Thank goodness for service providers, sites harvesting and storing metadata from various collections. I looked at four of these sites.

1. Sheet Music Consortium – The consortium is a partnership between John Hopkins University, UCLA, University of Indiana and Duke University Library.

2. Perseus- http://www.perseus.tufts.edu/ A digital library of resources for the study of the humanities

3. Geo-Leo http://www.geo-leo.de/geoleo/www-docs/?language=en collects records in the subject areas Geology, Mineralogy, Petrology, Soil Science, Mining, Geophysics, Geography and Thematic Maps.

4. Citebase http://www.citebase.org/search "Citebase contains articles from physics, math, information science, and (published only) biomedical papers>"

A useful federated collection is based on records where there exists a commonality in the metadata and that enhances your research in some way. Each of these services fulfilled that need for the most part. Perseus returned over 1,000 hits on the search "railroad stations United States." This can be attributed to the Library of Congress being one of the sites searched. Also, Perseus returned irrelevant records including a sheep shearing station in Australia. The other sites returned data as I expected. Oh yes, one other reason why harvesting is good, there is the fact that you are only doing one search instead of searching individual sites.

The University of Michigan's mega repository Oaister http://www.oaister.org/ indexes about 15M records from nearly 1000 contributors. This is one of those cases where size matters and helps the cause. The advantage is you have the potential of more sources returning more useful records making for a stronger federated search Should this be your only source for information? Probably not, your research plan should include a look in more then one repository.