by

Keith May @Keith_May Ceri Binding & Prof Doug Tudhope

Faculty of Advanced Technology University of South Wales

To Boldly or Bravely Go? Experiences of using Semantic Technologies for

Archaeological Resources

Excavation record data modelling

• CRM-EH focuses on common ‘core’ Concepts of our Archaeological processes

• Stratigraphic relationships (e.g. Harris matrix) crucial for relating individual records

• Mapped only a Limited degree of the minute archaeological detail to CIDOC CRM

• Different broad categories of contexts (Deposits, Masonry, Timber, etc) handled by separate forms but modelled together

• Model already "complex" enough - most archaeologists find it a little daunting

Details of Context on recording

form

What about comparing records across different countries?

With thanks to Anja Masur

Documentation• Different excavation methods bring differing documentation • Comparison of different documentation sheets

Similarities and Differences

Context

LocusExcavation

Unit

Lot

Level

StratumBehälter (Troy)

(Basket)

Semantics One language - one meaning – different terms

Stratigraphic Unit

With thanks to Gerald Hiebel

English Heritage Recording Manual

English Heritage Recording Manual with CRM-EH 'Extensions'

German - e.g. Gottingen & Bayer

Befunde - Stratigraphic Unit / Context

1. Bayer -Befundbuch (positive deposit?)

Bodenbefunde (soil SU)

Baubefunde (built SU e.g. Walls)

BefundeKomplex - Feature (Group)

Planum = Multi-context plans by level?

With thanks to Gerald Hiebel

Bavarian Recording Manual

Catalhoyuk - Hodder's 'Post-Processual' excavation recording

Units - Stratigraphic units, similar to Contexts

Features - groupings of units or more complex structures, similar to

MoLA Groups

French - e.g. ???? Please !!!!

Examples using Single Context Recording methodology?

INRAP N'est pas?

Other excavation methodologies?

Prototype Controlled Vocabulary searching

▪Controlled vocabularies online ▪Vocabularies from EH, RCAHMS, RCAHMW ▪Conversion to a common standard format (SKOS) ▪Persistent globally unique identifiers for every concept ▪Made available online as Linked Open Data ▪Also downloadable data files and listings

▪Web services ▪Facilitate concept searching, browsing, suggestion, validation

▪ Tools to use controlled vocabularies ▪Browser-based ‘widget’ user interface controls ▪Search, browse, suggest, select concepts

▪Case studies ▪Legacy data to thesaurus alignment ▪Thesaurus to thesaurus alignment ▪Third party use of project outcomes

STELLAR Project Tools - SKOS TemplateSKOS = Simple Knowledge Organisation System

Using SKOS - W3C standard for Web-based Terminologies

skos:Concept Castle:c789

skos:Concept Motte:c456

skos:broader skos:narrower

skos:Concept Bailey:c789

skos:Concept Motte:c456

skos:related skos:related

skos:ConceptScheme Monument:s123

skos:Concept Motte:c456

skos:inScheme

SKOS_CONCEPTS – scheme_id, broader_id, related_id

Voacabulary Widgets – e.g. for OASIS ▪ Scheme list ▪ Scheme details ▪ Top concepts ▪ Composite control

(composite control)(top concepts)

(scheme details)

(scheme list) More Widget details on HeritageData.org

LOD Heritage Vocabularies: http://www.heritagedata.org

Thesaurus searching and browsing

- Semantic ENrichment Enabling Sustainability of arCHAeological LinksSENESCHAL

Early adoption (continued)▪Clwyd-Powys Archaeological Trust (SENESCHAL widgets

embedded into HER application and mobile field recording app)

British Oceanographic Data Centre - LOD

EH Thesauri of Maritime

Craft

With Thanks to Adam Leadbetter

Typical alignment problems encountered▪ Simple spelling errors ▪ POSTHLOLE”, “CESS PITT”, “FURRROWS”, FLINT SCRAPPER”

▪ Alternate word forms ▪ “BOUNDARY”/”BOUNDARIES”, “GULLEY”/”GULLIES”

▪ Prefixes / suffixes ▪ “RED HILL (POSSIBLE)”, “TRACKWAY (COBBLED)”, “CROFT?”, “CAIRN (POSSIBLE)”,

“PORTAL DOLMEN (RE-ERECTED)” ▪ Nested delimiters ▪ “POTTERY, CERAMIC TILE, IRON OBJECTS, GLASS”

▪ Terms not intended for indexing ▪ “NONE”, “UNIDENTIFIED OBJECT”, “N/A”, “NA”, “INCOHERENT”

▪ Terms that would not be in (any) thesauri ▪ “WOTSITS PACKET”, “CHARLES 2ND COIN”, “ROMAN STRUCTURE POSSIBLY A VILLA“,

“ST GUTHLACS BENEDICTINE PRIORY”, “WORCESTER-BIRMINGHAM CANAL”, “KUNGLIGA SLOTTET”, “SUB-FOSSIL BEETLES”

▪ More specific phrases ▪ “SIDE WALL OF POT WITH LUG”, “BRICK-LINED INDUSTRIAL WELL OR MINE SHAFT”,

“ALIGNMENT OF PLATFORMS AND STONES”

Data alignment - R&D approach

▪Levenshtein edit distance algorithm ▪ Measures optimal number of character edits

required to change one string into another ▪ Accommodates small spelling differences/errors ▪ Bulk alignment process ▪ Compares each value to all terms from specified

thesaurus – obtain best textual match ▪ Similarity threshold introduced to suppress low

scoring matches. Levenshtein algorithm will always produce a match, even if it is a bad one!

▪ Periods require an additional approach due to mixed formats (named periods, numeric ranges etc.)

Data Alignment R&D Results – Monument Types

Needs some level of Human verification by

Domain experts. Do we need semantic

wiki -style interfaces

To enable that?

Conclusions and Challenges - Do you want to share Open Archaeological Data

somewhere on or over the horizon?

Different archaeological recording systems share common conceptual frameworks and semantic relationships

By conceptualising common relationships in our different data sets at a broad (metadata) level and aligning vocabularies of shared reference terms we can cross-search data with more semantic accuracy to find patterns and answers to related research questions

The technologies are being developed in other domains but is there a common will for sharing archaeological data Openly in the interests of improving research methods?

References

Catalin Pavel. "Describing and Interpreting the Past" Tudhope, May, Binding, Vlachidis. "Connecting Archaeological Data and Grey Literature via Semantic Cross Search" - Internet Archaeology Vol 30

Contact: Keith.May@english-heritage.org.uk

@Keith_May