1. The Library of Online Harmonisations
Martin Friedrichs and Kristi Winters EDDI 2016
License CC BY 4.0

2. Introduction
Harmonizing variables is an important part of social science research.
But for variable harmonization work to be of scientific value the harmonisation process must be documented and published in a precise and transparent ways.
However even if done so these intellectual contributions are often lost because researchers can’t publish their work.
Our solution is an online library where digitally documented harmonisation routines will be archived and accessed.

3. Overview
L.o.H

4. “Nice. But what is the relationship to DDI?”
Question
“Nice. But what is the relationship to DDI?”

5. Answer
Such a platform requires metadata and data harmonisation workflow to be represented in a standardized and machine actionable way.
As it is now harmonisation routines arise from different sources, like SPSS, Stata or as output from applications like CharmStats.
These very different types of harmonisation routines should be represented by a single standard inside the library.
We also need a standard for exchanging said “digitally documented harmonisation routines” with tools outside the library.
Our idea is to combine these two requirements and to use an XML based representation for both of them.
Which brings us to DDI.

6. DDI

7. Larry Hoyle and Joachim Wackerow
„DDI as a Common Format for Export and Import for Statistical Packages“

8. In this article published 2015 in IASSIST Quarterly the authors presented an experiment using Stat/Transfer to exchange datasets between software packages with DDI Lifecycle as the „standard representation“.

9. Their conclusion
„Adoption of DDI by tools like Stats/Transfer is encouraging. Basic metadata is transferable among all 5 packages via DDI.
The current state still means that some important metadata […] still must be either hand entered into DDI or harvested and entered by user-witten code.“ (pg. 20)

10. Digitally documented harmonisation routines
Charmstats

11. About CharmStats (CS)

12. Overview CS Datamodel Study AttributeComp Question Project
InstanceLink
Instance
AttributeLink
Variable
CharLink
Value
InstanceMap
AttributeMap
CharMap

13. Overview CS Datamodel Study AttributeComp Question Project
InstanceLink
Instance
AttributeLink
Variable
CharLink
Value
InstanceMap
AttributeMap
CharMap

14. Overview CS Datamodel Study AttributeComp Question Project
InstanceLink
Instance
AttributeLink
Variable
CharLink
Value
InstanceMap
AttributeMap
CharMap

15. Overview CS Datamodel Study AttributeComp Question Project
InstanceLink
Instance
AttributeLink
Variable
CharLink
Value
InstanceMap
AttributeMap
CharMap

16. Overview CS Datamodel Study AttributeComp Question Project
InstanceLink
Instance
AttributeLink
Variable
CharLink
Value
InstanceMap
AttributeMap
CharMap

17. Overview CS Datamodel Study AttributeComp Question Project
InstanceLink
Instance
AttributeLink
Variable
CharLink
Value
InstanceMap
AttributeMap
CharMap

18. The Hidden Elements
Measurement
Dimension
Indicator
Variable

19. Overview CS Datamodel InstanceLink S. Inst. AttributeLink Measure
CharLink
Category
InstanceLink
C. Inst.
AttributeLink
Dimension
CharLink
Specification
InstanceLink
O. Inst.
AttributeLink
Indicator
CharLink
Prescription
Project
InstanceLink
D. Inst.
AttributeLink
Variable
CharLink
Value

20. Overview CS Datamodel InstanceLink S. Inst. AttributeLink Measure
CharLink
Category
InstanceLink
C. Inst.
AttributeLink
Dimension
CharLink
Specification
InstanceLink
O. Inst.
AttributeLink
Indicator
CharLink
Prescription
Project
InstanceLink
D. Inst.
AttributeLink
Variable
CharLink
Value
InstanceMap
AttributeMap
CharMap

21. Overview CS Datamodel InstanceLink S. Inst. AttributeLink Measure
CharLink
Category
InstanceLink
C. Inst.
AttributeLink
Dimension
CharLink
Specification
InstanceLink
O. Inst.
AttributeLink
Indicator
CharLink
Prescription
Project
InstanceLink
D. Inst.
AttributeLink
Variable
CharLink
Value
InstanceMap
AttributeMap
CharMap

22. Overview CS Datamodel InstanceLink S. Inst. AttributeLink Measure
CharLink
Category
InstanceLink
C. Inst.
AttributeLink
Dimension
CharLink
Specification
InstanceLink
O. Inst.
AttributeLink
Indicator
CharLink
Prescription
Project
InstanceLink
D. Inst.
AttributeLink
Variable
CharLink
Value
InstanceMap
AttributeMap
CharMap

23. DDI and the CS Model

24. Variable Variable VariableType Name VariableName Label r:Label Level
r:VersionableType
Variable
VariableType
Name
VariableName
Label
r:Label
Level
MeasureType
Question
r:QuestionReference
Dataset
DatasetLabel
PID
DateLastChanged
r:Description …
Temporal*
isTemporal
Geographic*
isGeographic
isWeight

25. Variable Variable Project InstanceLink Instance AttributeLink Variable
CharLink
Value
InstanceMap
AttributeMap
CharMap

26. Instance Instance VariableSchemeType VariableGroupType Label
r:Maintainable
r:Versionable
Instance
VariableSchemeType
VariableGroupType
Label
VariableSchemeName
VariableGroupName
r:Label
Type
TypeOfVariableGroup
PublishedSince*
ObsoleteSince*
Description
r:Description
r:VariableSchemeReference
r:UniverseReference
r:ConceptReference
r:Subject
r:Keyword
Variable
r:VariableReference
VariableGroup
r:VariableGroupReference
isOrdered

27. Instance V. Scheme V. Group Variable Project InstanceLink Instance
AttributeLink
Variable
CharLink
Value
InstanceMap
AttributeMap
CharMap

28. References, Links and Maps
InstanceLink
AttributeLink
CharacteristicLink ID
Project
Instance
Attribute
Characteristic
InstanceLinkType
AttributeLinkType
CharacteristicLinkType
InstanceMap
AttributeMap
CharacteristicMap ID
SourceInstanceLink
SourceAttributeLink
SourceCharacteristicLink
TargetInstanceLink
TargetAttributeLink
TargetCharacteristicLink
InstanceMapType
AttributeMapType
CharacteristicMapType
Project
ConceptRef
Referenced
Concept
RefRelationshipType
<xs:complexType name="ReferenceType">
<xs:sequence>
<xs:choice minOccurs="1" maxOccurs="2">
<xs:element ref="URN"></xs:element>
<xs:element ref="Agency"></xs:element>
<xs:element ref="ID"></xs:element>
<xs:element ref="Version"></xs:element>
</xs:sequence>
</xs:choice>
<xs:element ref="TypeOfObject"></xs:element>
<xs:element ref="MaintainableObject" minOccurs="0"></xs:element>
<xs:attribute name="isExternal" type="xs:boolean" default="false"></xs:attribute>
<xs:attribute name="externalReferenceDefaultURI" type="xs:anyURI" use="optional"></xs:attribute>
<xs:attribute name="isReference" type="xs:boolean" fixed="true"></xs:attribute>
<xs:attribute name="lateBound" type="xs:boolean" default="false"></xs:attribute>
<xs:attribute name="lateBoundRestriction" type="VersionType" use="optional"></xs:attribute>
<xs:attribute name="objectLanguage" type="LanguageList" use="optional"></xs:attribute>
<xs:attribute name="sourceContext" type="xs:anyURI" use="optional"></xs:attribute>
</xs:complexType>

29. AttributeLink? Problem: We can‘t refer to r:VariableRef V. Scheme
V. Group
r:VariableRef
Variable
Project
InstanceLink
Instance
AttributeLink
Variable
CharLink
Value
InstanceMap
AttributeMap
CharMap
Problem: We can‘t refer to r:VariableRef

30. „AttributeLink“ Variable V. Scheme V. Group Project InstanceLink
CharLink
Value
InstanceMap
AttributeMap
CharMap

31. AttributeMap Variable V. Scheme V. Group Project InstanceLink Instance
AttributeLink
Variable
CharLink
Value
InstanceMap
AttributeMap
CharMap
V. Scheme
V. Group
r:VariableRef

32. Project ResourcePackage Variable V. Scheme V. Group Project
InstanceLink
Instance
AttributeLink
Variable
CharLink
Value
InstanceMap
AttributeMap
CharMap
V. Scheme
V. Group
r:VariableRef

33. „InstanceLink“ ResourcePackage Variable V. Scheme V. Scheme V. Group
Project
InstanceLink
Instance
AttributeLink
Variable
CharLink
Value
InstanceMap
AttributeMap
CharMap
V. Scheme
V. Group
r:VariableRef

34. „InstanceMap“ ResourcePackage Variable V. Scheme V. Scheme
V. SchemeRef
V. Group
Project
InstanceLink
Instance
AttributeLink
Variable
CharLink
Value
InstanceMap
AttributeMap
CharMap
V. Scheme
V. Group
r:VariableRef

35. Conclusion
To replicate the CS model as it was implemented with DDI is not possible
The simulate the idea behind the CS model with DDI might be possible
Further research is necessary

36. Thank you for your patience!