Presentation on theme: "Matrix Schema Tutorial Presented at the: IX European Banking Supervisors XBRL Workshop & Tutorial In: Paris On: 29th September 2008 By: Michele Romanelli."— Presentation transcript:
Matrix Schema Tutorial Presented at the: IX European Banking Supervisors XBRL Workshop & Tutorial In: Paris On: 29th September 2008 By: Michele Romanelli Member of CEBS XBRL Network
Agenda Introduction – What is a matrix schema Change management approaches A deeper view on matrix schemas Conclusions
what business people ask for what technical people deliver what technical people say theyve done How to guarantee consistency among requirements, taxonomy and documentation ? The problem: how to align business and technical view
In COREP & FINREP contexts: A method to visualize a complex multidimensional taxonomy Based on a matrix where: Row headers are the concepts to be reported Column headers are the involved dimension Cells determine: (i) if the dimension applies to the concept and (ii) what are the allowed/disallowed values for that dimension What is a Matrix Schema?
An Example of a matrix schema Column headers: Dimensions used in the template Row headers: Primary items Each row describes the breakdown structure of a primary item Each cell contains a code that stands for the list of members allowed for the dimension in the primary item. A sheet for each extended link
An Example of domain sheet
Very compact format Useful as a tool to verify the matching between business requirements (normally expressed through templates) and technical implementation (XBRL taxonomy) understanding of COREP/FINREP taxonomies by supervised entities (hopefully) easier. Easy to build and to understand; for COREP & FINREP, it is automatically derived from XBRL taxonomies through a reverse- engineering software. Main advantages
Taxonomy creation: the current path From the business template (presentation centric view)… … to the taxonomy (technical view) … … to the matrix schema (data centric view): Reconciliation
Taxonomy creation: an alternative path User view: both business template and corresponding draft matrix schema Taxonomy building: no technical experts interpretation of business requirements Matrix schema derived from the taxonomy Reconciliation based on comparison between input and output matrix schemas
Change Management approaches In the near future both FINREP and COREP need to be amended. Change the template only and build the taxonomy from scratch? What about a different approach?
Template vs. Matrix schema Templates are mainly concerned with the presentation layer Matrix schemas are mainly concerned with the data definition layer The harmonisation should be sought at the data level
Transformations Data structures Reusable Concepts Taxonomy 4 Taxonomy 2 Taxonomy 3 Taxonomy 1 Matrix model: a layered, conceptual tool
Domains (or Sets) –Example: the set of European Cities, or the set of Exposure Classes Members (or domain-members) –Example: a single European city (Paris, Rome, …) or a single Exposure Class (Institutions, Corporates, …) Dimensions –A specific meaning of a Domain (example: the city of birth, the city of residence, the city of work) Measures (or primary-items) –aspects we want to observe Concepts in matrix model
Data Structures: Relationships among concepts Primary Item Dimension DomainSub-Domain Member Is observed through Is defined on Takes values in Is a subset of Contains hierarchies Are organized into
Building the Matrix schema 1.Think about what you want to observe: Primary Items 2.Think about break-down structures you are interested in: Dimensions 3.Ask yourself if these dimensions are new ones or existing ones; assign a name only to new ones; 4. Ask yourself which is the general domain of these new dimensions: is it an existing one? Do you need a new one?
Building the Matrix schema /2 5.Define members for newly created domains 6.Link appropriate dimensions to the primary item 7.Ask yourself if, in that relationship, the dimension is allowed to assume all the values of its general domain; if not, identify or define a sub-domain 8.Link the dimension to the general domain or one of its sub-domains as appropriate
Building the Matrix schema: complex issues Disallowing specific combinations Reporting a primary item for two (or more) different break-down structures Hierarchies of primary items (just for presentation?) Hierarchies of members (just for presentation? Or necessary to specify roll-up/drill-down operations?) Modelling tables with a non-evident distinction between measures and dimensions
Example of disallowed combinations and multiple break-down structures
Example of tables with non-intuitive distinction between measures and dimensions
Conclusions Matrix schema as a simple, conceptual tool Suitable to be automated Good chance to automatically generate the taxonomy from the matrix schema No reconciliation needs Shorter time-to-market