Same as it ever was? Significant Properties and the preservation of meaning over time

Same as it ever was? Significant Properties and the preservation of meaning over time

Stephen Grace and Gareth Knight

Centre for e-Research

2

Why Significant Properties?

“The fundamental challenge of digital preservation is to preserve the accessibility and authenticity of digital objects over time and domains, and across changing technical environments”

Wilson, 2008

InSPECT Significant Properties Report

3

http://www.flickr.com/photos/marcn/2175740608/Attribution 2.0 Generic

4

Change we can believe in

“We want to be able to guarantee that for a given object the reformatted version is equivalent to the original version with regards to some specific set of object characteristics”

Clifford Lynch, DLib 1999

If we change something in order to keep it safe, how do we know we can trust the results? And how do we reassure others?

5

InSPECT definition of SPs

The characteristics of digital objects that must be preserved over time in order to ensure the continued accessibility, usability, and meaning of the objects

Wilson, 2008

InSPECT Significant Properties Report

6

Authenticity, integrity, viability

• Authenticity – is this what it purports to be?

• Integrity – is this complete and “unaltered”?

• Viability – is this suitable for its audience (the Designated Community in OAIS terms)?

7

What is significant about the digital object?• How do you distinguish between essential, useful and superfluous?

• Impractical to present a single, definitive interpretation of significance

• Many stakeholders may be associated with an object

• Stakeholders vary and change over time• Stakeholders have different needs and knowledge

8

InSPECT approach to determining significance

• Formal methodology required to guide process of identifying, analysing and recording elements of the Information Object that are essential/beneficial to maintain over time

• Assessment framework should be rational, consistent in its application, while offering sufficient flexibility for widespread applicability

• Previous work performed in field, such as Rothenberg & Bikson’s Needs Analysis, InterPARES1 use of Diplomatics and PLANETS Utility Analysis methodologies

9

Significance is human

• Need to adopt a relativistic approach to determine aspects that are essential/beneficial based upon an interpretation of acceptable loss

• InSPECT builds upon two philosophical approaches:

• Teleology: study of design and purpose of object – why was it created?

• Epistemology: Understand meaning and process by which knowledge is acquired

• In combination, these encourage evaluation of context of creation and information needed to communicate intrinsic knowledge to a new audience (designated community)

10

SP assessment framework in InSPECT• Builds on Gero’s Function-Behaviour-Structure framework• Three categories:

• Function: The design intention or purpose that is performed

• Behaviour: The epistemological outcome derived from the function & structure obtained by the stakeholder

• Structure: The structural elements of the Object that enables stakeholder to perform a behaviour

• Behaviour is result of Function and Structure interaction

11

Assessment framework stages

• Object analysis• Identify functions, behaviours to be achieved

and properties needed for their performance

• Stakeholder analysis• Analyse functions a particular user group wish

to perform

• Reformulation• Perform a revised set of functions or different

behaviours

12

Analyse structure

Identify purpose of technical properties

Determine expected behaviours

Classify behaviours into functions

Associate properties with each

function

Review & finalise

Select object type for analysis

1. Object Analysis

13

Select object type(s) for analysis

Determine actual behaviours

Classify behaviours into set of functions

Object type analysis

Stakeholder requirements analysis

Assign acceptablevalue boundaries

Review & finalise

Finalise & record

Identify stakeholder

Cross-match functions

2. Stakeholder Analysis

14

3. ReformulationRedevelop object to perform a revised set of functions

or enable different behaviours (e.g. view, use)

Object type properties as req. by functions

Cross-match

Functions required by stakeholder

ReformulateInformation Object for use by stakeholder A

Information Object for use by stakeholder B

15

Reformulation in practice

http://www.flickr.com/photos/huggerindustries/3885401876/

Attribution-Non-Commercial-Share Alike 2.0 Generic

http://www.flickr.com/photos/mvjantzen/4113615243/ Attribution-Non-Commercial 2.0 Generic

16

dismantle

Object Analysis

Re-formulation

Stakeholder 1 Analysis

Archiving

Re-formulation


Re-formulation

Stakeholder 1 Re-Analysis

Re-formulation


Construction

Time

dismantle

Analysis & reformulation over time

17

SPs in digital preservation

• Document technical properties

• Describe intellectual entities

• Determine preservation priorities

• Measure the success of transformations• Choices, outcomes, relation to original

18

SPs in repository workflows

•Availability and adequacy of characterisation tools• (Partly) manual activity for the foreseeable future

•Encoding for machine processing• Requires a metadata schema e.g. extensions to PREMIS

•Possibility of standard ‘profiles’ over time• Sharing results and best practice

•Always relate to institutional mission• Whose needs are being served?

19

Findings of InSPECT

•Appraisal process required to identify aspects of digital object that are essential

•Analysis of functional requirements is a pragmatic method for determining acceptable loss

•Significance is fluid – variable and subject to change

•Methodology provides a vocabulary and framework for understanding design process

20

In conclusion

Significant Properties can act as a bridge

across time to ensure the persistence of

what is important in digital objects through

any required transformations

Grace, Knight and Montague 2009

InSPECT Final Report

21

Acknowledgments

InSPECT was funded by JISC and was a

collaboration between the Centre for

e-Research at King’s College London and

The National Archives

22

Contact us

Stephen Grace


King’s College London

[email protected]

020 7848 1972

Gareth Knight


King’s College London

[email protected]

020 7848 1979

www.significantproperties.org.uk

www.kcl.ac.uk/iss/cerch