A New Approach to Coin Hoard Documentation

For several months, we have been hard at work developing an XML representation of coin hoard documentation.  The data model, a derivative/relation of NUDS-XML (thus also influenced by other formats such as EAD and RDF), is still very much a draft, but one constantly growing in stability. It is, in theory, capable of meeting the requirements of various institutions.  Groups of coins can be encoded by general typologies, e.g., total number of denarii or total coins of a particular issuer or material.  Groups of coins can point to nomisma ids for specific coin-types, like RRC or RIC numbers.  Individual coins can also be described by precise physical measurements or attributes--counterstamps, weights, diameters--or point to URIs that represent those physical specimens online.

Let us examine the following XML snippet:

Coins and coinGrps can include any NUDS element from the descMeta--Physical, Typological, Reference Descriptions, etc.  Like in NUDS, the nuds:typeDesc can point to a URI (in this case, a nomisma ID) with the semantic xlink:href attribute (very much like METS, EAD, EAC-CPF, and other XML standards).

A coin hoard may contain hundreds of distinct coin-types, but if these coin types are represented by nomisma IDs, the typological attributes do not need to be encoded directly within the hoard XML document.  This not only enables the hoard documents to be fairly compact and concise, but also removes the burden of upkeep from the editors of hoard records, since the nomisma IDs are considered canonical representations of coin-type metadata.

When rendering the hoard XML document into HTML, Numishare can parse the RDF from the nomisma ID dynamically to render the following output:

The hoard contents are formatted in a table similar to what numismatists are accustomed, but rows can be expanded to see the full typological description, with links to nomisma, Wikipedia, and Pleiades.  The format of this descriptive information is identical to that of physical coins and coin-types because the code is, in fact, identical.  The closing date of the hoard can be established by parsing this collection of coin-type metadata even if the dates are not stored directly in the hoard record.  The disadvantage of this framework, of course, is that it is more processor intensive than querying and rendering data stored directly in a database.  It may take several seconds to render a large hoard document into HTML, but I think the advantages of this framework far outweigh the disadvantages.

In addition to rather simple output of descriptive metadata is a feature for quantitative analysis.  This feature is very powerful, though rudimentary, having been developed in only two work days.  It will grow in its sophistication over time.

Like coin-types, there is a quantitative analysis tab on the web page for a hoard record.  The user can select from a handful of typological attributes to generate bar graphs. We are using highcharts for this instead of jQuery visualize, like other visualizations in Numishare.  I have found it to be far more versatile, and we will eventually replace jQuery visualize with highcharts everywhere in Numishare.

Highcharts is capable of other chart and graph formats, different colors, and outputting a printable chart.  I have only begun to explore these options.

The next major task to pursue is to output findspot points to the map on the hoard record HTML page.

Numismatic Description Standard: A Draft

A number of blog posts have mentioned NUDS-XML, our approach to interpreting the Numismatic Database Standard fields listed by Sebastian Heath on nomisma.org as an XML data model.  NUDS-XML (which could be called "Numismatic Description Standard" since it is not technically a database schema) is an ontology applied to numismatic metadata, influenced by existing metadata standards like EAD, METS, and VRA Core, but also largely reliant on linked open data philosophies.  Many numismatic concepts can be linked to resources on nomisma.org through W3C xlink attributes.

While NUDS is still a draft and has not been codified in the form of XSD or Relax NG schemas, it is stable enough for development.  Numishare is designed to create, edit, and publish NUDS records for physical coins and conceptual coin-type objects.

Draft documentation for NUDS is now available through the ANS's wiki.

http://wiki.numismatics.org/nuds:nuds

Linking Roman Coins: Current Work at the American Numismatic Society

Several of the American Numismatic Society's current projects are going to be demonstrated at CAA 2012, to be held in Southampton, England next week.  CAA, Computer Applications and Quantitative Methods in Archaeology, is an interesting conferences that draws as many archaeologists as computer and information scientists, including many alt-ac people like myself who are a hybrid of the two fields.

Below is one of the slideshows that we will be presenting.

Linking Roman Coins: CAA2012

View more presentations from ewg118

It introduces nomisma.org and details our use of NUDS-XML and Numishare to create an open-access web-based version of Roman Imperial Coinage.  The demo is available at http://admin.numismatics.org/ocre.

Quantitative Analysis of Coin-Types

Among the American Numismatic Society's current projects is Online Coins of the Rome Empire (OCRE), which is a free, open-access catalog of Roman Imperial Coins.  Each coin type numbered in RIC will be represented with a nomisma URI.  A NUDS XML record will describe the typological attributes of the coin-type, as well as link to associated physical objects in various collections (Mantis, to start).  An early Numishare blog post describes this feature in more detail.  We will be presenting a prototype of OCRE at CAA in March (abstract).  The OCRE project not only provides stable URIs for coin-types, but also a user interface for searching, browsing, and mapping Roman Imperial Coins in the same manner of Mantis.

Since a coin-type record can point to related coins in other collections, Numishare can extract physical attributes of those coins, as well as findspots (if available).  The Solr index, for example, will ingest all of the weights of associated physical coins to ascertain the average weight and standard deviation for a coin-type.  The accuracy of these measurements improves proportionally to the number of coins from which the weights are derived.

Numishare currently supports comparing the average weight of a particular coin type to the average weights of associated facets, e.g., by the same authority, denomination, or material across the entire collection.  Eventually, it will support user-set queries: compare RIC Augustus 410 (a silver denarius) with other silver coins of Augustus and with silver coins of the late 3rd century AD.  These sorts of quantitative analyses will no doubt serve as a great resource to numismatists and ancient historians.

The general distribution of Numishare supports a quantitative analysis tab for coin-type records that have associated weight measurements.

The Kittredge Collection Gets a Facelift

The Kittredge Collection relaunched Sunday evening.  The Kittredge Numismatic Foundation was an early sponsor of Numishare directly after it had been released to the community as an open-source project and a proponent of many of its early features, including the XForms-based backend.  The data has been migrated to NUDS from Encoded Archival Description (for coins) and disseminated with the latest version of Numishare.  The data is still a work in progress; mints point to geonames.org URIs, while materials and object types point to nomisma.org URIs, but much work is left to be done to point other numismatic concepts to unique identifiers.

The Kittredge Collection contains all of the latest mapping and linked open data features detailed in this blog, as well some new additions--particularly the expandable date facet on the browse page that allows the user to select coins by century and decade (example: http://kittredgecollection.org/results?q=%28decade_num%3A1650+OR+decade_num%3A1670+OR+decade_num%3A1690%29).  This feature was ported over from EADitor.

Flickr Image Integration

Major updates have been underway in Numishare development over the last few months, as exhibited by the recent flurry of blog posts.  One of the more recent advances has been in integrating the flickr API into the Numishare administrative back end, enabling users to attach images from that web service to coin metadata records.  The process is fairly straightforward.  The user:

1. Signs up for flickr and requests an API key
2. Inputs the API key into the Numishare settings page and updates the settings
3. Opens a coin record and inserts an obverse or reverse image
4. Pastes a URL of a flickr image into the input box and clicks the "Attach" button

When the user clicks this button, an API lookup is called to receive URLs to available image sizes, and each URL is stored in METS elements embedded into the NUDS XML document.

When the coin is saved and published to the search index (Solr), the thumbnail and medium-sized images are stored so that they can be accessed from the search results page (and, obviously, from the coin record itself).

When clicking on the medium-sized images, the user is directed to the flickr URL for that object, per their terms of service.

Leveraging flickr's service for image storage and retrieval has numerous benefits, especially when a collector or institution may have a large body of image files, but not enough web space on the server on which Numishare is installed or if there is a wish to make just the images accessible through other media.  Flickr is a great alternative Numishare's default image uploading mechanism, Remotemagick, an XML-RPC service which is a front-end to imagemagick that interacts with Orbeon for uploading and resizing images.

Leveraging nomisma to Deliver Controlled Vocabulary Services

With the launch of the nomisma.org Atom feed just a few days ago, I went to work on developing an XForms component which leverages the service to deliver controlled vocabulary terms for ancient mints within the administrative backend of Numishare. Numishare's interface for creating and editing coins already included a connector to geonames.org's APIs for querying modern place names, which I have detailed on the EADitor blog.

The nomisma service operates in similar fashion. A user selects a "nomisma" radio button (versus the other options to query geonames or local controlled vocabulary stored in the Solr index), inputs a search term into a text box, clicks the search button which executes an xforms:submission to query the Atom feed (which populates an xforms:instance), and selects the appropriate option from the select list box, which is formed by each atom:entry returned by the query. An example is pictured below:


The nomisma URI is stored as an attribute in the mint element in the NUDS-XML record so that, upon indexing the record into the search index, a lookup is performed on the RDFa of the nomisma id to extract geographic coordinates, enabling mapping out of the box of ancient mints (in addition to modern mints that are supplied through the geonames service). As noted earlier, findspots are also mappable.


Additionally, if the nomisma RDFa includes a reference to the associated Pleiades place, the Pleiades URI is also stored in the search index, enabling querying of Numishare by that URI.

Code for XForms XBL component