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= Results =
For now this is a bullet pointed list which needs bulking out:
For now this is a bullet pointed list which needs bulking out:

Revision as of 12:48, 26 February 2009



For now this is a bullet pointed list which needs bulking out:

  • When harvesting repositories about 1/3 of downloads fail for various reasons, Further Investigation?
  • ROAR identifies a lot of stuff at HTML as it may get redirected to html in the process of trying to get a resource. This is wrong as this is not then the resource, the bug we believe is in the fact that the repository sends a HTTP 200 and not an HTTP 401 header. This is particularly the case on the ANU repository where we have only 74 items as fmt/94 (html) is the redirected 401 page. Further Investigation?
  • FIRST PARSE RESULTS (with the above correction)
    • All 994 files were located by the EPrints3.2 classification engine.
    • Only 45 objects were left unclassified which is better than the 129 which were UNKNOWN at the time of importation.
    • All other comparisons are difficult at this stage.
    • Some initial observations:
      • DROID is classifying the objects differently from the original classification however these are still the same in mime type. For example an HTML 4.0 file is now being classified as an XHTML or just HTML file. The same is true of text files and some PDFs. We suspect this is due to the Tentative classifications which DROID provides for some files. As a result we are now including the classification quality (tentative, positive) in the data output from a classification.
    • update_pronom_uids scripts tries to process NULL and thus dies because it receives an error 400, technically it should only die if the service is not reachable, or just do it on a per object basis.
    • In the philsci repository the number of files with pronomids is correct but the division by mime-type is wrong.
    • No error handling on the formats_risks page if nothing has been classified!
    • The files missing bug was a problem with the script generating the EP3XML not escaping URLs correctly. With this fixed all repositories populate correctly. NEED TO SUBMIT THIS TO GOOGLE CODE OR SOMETHING?

The Differences

  • ROAR: DROID v1.2 with signature file version 12.
  • Preserv2-EPrints-Toolkit: DROID v3.0 with signature file version 13.

General Observations

  • The Preserv2-EPrints-Toolkit version of DROID has issues when trying to differentiate between different types of text and rtf files.
  • As a result it classifies them all as one type.
  • Pronom is lacking a complete set of mime-types for its format data, which is key when it comes to changing identifiers.
  • The Preserv2-EPrints-Toolkit version of DROID is able to classify more objects, cutting down on the number of unknowns
  • Some files have been updated in the base repositories but remain of the same mime-type. DROID classification error or manual user update, unfortunately there is no way to tell.

Typical Repository Outcomes (994 Files)

  • 2 files, previously of known format are now unknown? #
  • Out of the 994 files only 83 remain concerning with 43 still unknown and 40 not matching their original classification even by mime-type. Of the remaining files 567 matched exactly to their previous classification and 256 (most likely text and rtf) matched by mime type. This backs the general conclusion about DROID v3.00 with sig file v13 has issues determining the exact file version of some types of simple file.
    • 184 text files changed classification but stayed of the same mime-type.
    • 45 tiff files changed classification but stayed of the same mime-type.

Specific Repository Outcomes

Philsci (94 Files)

  • 10 objects classified which were previously unknown.
  • 75 exact matching classifications and 6 matching on mime-type (All text/rtf files)
  • 5 remain unknown.

Senado (99 Files)

  • 89 unknown on input, 89 unknown on output
    • All of these 89 files were in fact only 2 files which were provided by the publication URL.
    • Due to the fact I can't read Brazilian/Spanish I think that these pages represent a page describing a method to get at the document such as payment required (HTTP 414) or resource unavailable (HTTP 404). The pages are malformed html which don't provide an HTTP header code (as stated by me) to describe their page. Basically a very bad web site implementation Web < 0.1.
  • All other classifications matched exactly.
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