Changes for page SDMX 3.1 Standards. Section 1. Framework

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@@ -159,7 +159,7 @@
  [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] identifies three basic process patterns regarding the exchange of statistical data and metadata. These can be described as follows:
--1. //**Bilateral exchange**~:// All aspects of the exchange process are agreed between counterparties, including the mechanism for exchange of data and metadata, the formats, the frequency or schedule, and the mode used for communications regarding the exchange. This is perhaps the most common process pattern.
++1. //**[[Bilateral exchange>>doc:sdmx:Glossary 2\.1.Bilateral exchange.WebHome]]**~:// All aspects of the exchange process are agreed between counterparties, including the mechanism for exchange of data and metadata, the formats, the frequency or schedule, and the mode used for communications regarding the exchange. This is perhaps the most common process pattern.
 . //**Gateway exchange**~:// Gateway exchanges are an organized set of [[bilateral exchanges>>doc:sdmx:Glossary 2\.1.Bilateral exchange.WebHome]], in which several data and metadata collecting organizations or individuals agree to exchange the collected information with each other in a single, known format, and according to a single, known process. This pattern has the effect of reducing the burden of managing multiple [[bilateral exchanges>>doc:sdmx:Glossary 2\.1.Bilateral exchange.WebHome]] (in data and metadata collection) across the sharing organizations/individuals. This is also a very common process pattern in the statistical area, where communities of institutions agree on ways to gain efficiencies within the scope of their collective responsibilities.
 . //**Data-sharing exchange**~:// Open, freely available data formats and process patterns are known and standard. Thus, any organization or individual can use any counterparty’s data and metadata (assuming they are permitted access to it). This model requires no bilateral agreement, but only requires that data and metadata providers and consumers adhere to the standards.
@@ -176,11 +176,11 @@
  == 3.3 Statistical Data and Metadata ==
--To avoid confusion about which "data" and "metadata" are the intended content of the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] formats specified here, a statement of scope is offered. Statistical "data" are sets of often numeric observations which typically have time associated with them. They are associated with a set of metadata values, representing specific concepts, which act as identifiers and descriptors of the data. These metadata values and concepts can be understood as the named [[dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] of a multi-dimensional co-ordinate system, describing what is often called a "cube" of data.
++To avoid confusion about which "data" and "metadata" are the intended content of the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] formats specified here, a statement of scope is offered. Statistical "data" are sets of often numeric observations which typically have time associated with them. They are associated with a set of metadata values, representing specific (% style="color:#e74c3c" %)concepts(%%), which act as identifiers and descriptors of the data. These metadata values and (% style="color:#e74c3c" %)concepts(%%) can be understood as the named [[dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] of a multi-dimensional co-ordinate system, describing what is often called a "cube" of data.
  [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] identifies a standard technique for modelling, expressing, and understanding the structure of this multi-dimensional "cube", allowing automated processing of data from a variety of sources. This approach is widely applicable across types of data and attempts to provide the simplest and most easily comprehensible technique that will support the exchange of this broad set of data and related metadata.
--The term "metadata" is very broad indeed. A distinction can be made between “structural” metadata – those concepts used in the description and identification of statistical data and metadata – and “reference” metadata – the larger set of concepts that describe and qualify statistical [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] and processing more generally, and which are often associated not with specific observations or [[series>>doc:sdmx:Glossary 2\.1.Series.WebHome]] of data, but with entire collections of data or even the institutions which provide that data.
++The term "metadata" is very broad indeed. A distinction can be made between “structural” metadata – those (% style="color:#e74c3c" %)concepts(%%) used in the description and identification of statistical data and metadata – and “reference” metadata – the larger set of (% style="color:#e74c3c" %)concepts(%%) that describe and qualify statistical [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] and processing more generally, and which are often associated not with specific observations or [[series>>doc:sdmx:Glossary 2\.1.Series.WebHome]] of data, but with entire collections of data or even the institutions which provide that data.
  The [[SDMX Information Model>>doc:sdmx:Glossary 2\.1.SDMX Information Model.WebHome]] provides for the structuring not only of data, but also of “reference” metadata. While these [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] structures exist independent of the data and its [[structural metadata>>doc:sdmx:Glossary 2\.1.Structural metadata.WebHome]], they are often linked. The [[SDMX Information Model>>doc:sdmx:Glossary 2\.1.SDMX Information Model.WebHome]] provides for the attachment of [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] to any part of the data or [[structural metadata>>doc:sdmx:Glossary 2\.1.Structural metadata.WebHome]], as well as for the reporting and exchange of the [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] and its structural descriptions. This function of the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] standards supports many aspects of data quality initiatives, allowing as it does for the exchange of metadata in its broadest sense, of which quality-related metadata is a major part.
@@ -194,13 +194,13 @@
  This document specifies the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] standards designed to facilitate exchanges based on any of these process patterns, and shows how [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] offers advantages in all cases. It is possible to agree bilaterally to use a standard format (such as [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]] or [[SDMX-JSON>>doc:sdmx:Glossary 2\.1.SDMX-JSON.WebHome]]); it is possible for data senders in a gateway process to use a standard format for [[data exchange>>doc:sdmx:Glossary 2\.1.Data exchange.WebHome]] with each other, or with any [[data providers>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]] who agree to do so; it is possible to agree to use the full set of [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] standards to support a common data-sharing process of exchange, whether based on an [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]-conformant registry or some other architecture.
--The standards specified here specifically support a data-sharing process based on the use of central registry services. Registry services provide visibility into the data and metadata existing within the community, and support the access and use of this data and metadata by providing a set of triggers for automated processing. The data or metadata itself is not stored in a central registry – these services merely provide a useful set of metadata about the data (and additional metadata) in a known location, so that users/applications can easily locate and obtain whatever data and/or metadata is registered. The use of standards for all data, metadata, and the registry services themselves is ubiquitous, permitting a high level of automation within a data-sharing community.
++The standards specified here specifically support a data-sharing process based on the use of central registry services. Registry services provide visibility into the data and metadata existing within the community, and support the access and use of this data and metadata by providing a set of triggers for automated processing. The data or metadata itself is not stored in a central registry – these services merely provide a useful set of metadata about the data (and additional metadata) in a known location, so that users/applications can easily locate and obtain whatever data and/or metadata is registered. The use of standards for all data, metadata, and the registry services themselves is ubiquitous, permitting a high (% style="color:#e74c3c" %)level(%%) of automation within a data-sharing community.
  It should be pointed out that these different process models are not mutually exclusive – a single system capable of expressing data and metadata in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]-conformant formats could support all three scenarios. Different standards may be applicable to different processes (for example, many registry services interfaces are used only in a data-sharing scenario) but all have a common basis in a shared information model.
  In addition to looking at collection and reporting, it is also important to consider the dissemination of data. Data and metadata – no matter how they are exchanged between counterparties in the process of their development and creation – are all eventually supplied to an end user of some type. Often, this is through specific applications inside of institutions. But more and more frequently, data and metadata are also published on websites in various formats. The dissemination of data and its accompanying metadata on the web is a focus of the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] standards. Standards for statistical data and metadata allow improvements in the publication of data – it becomes more easily possible to process a standard format once the data is obtained, and the data and metadata are linked together, making the comprehension and further processing of the data easier.
--In discussions of statistical data, there are many aspects of its dissemination which impact data quality: data discovery, ease of use, and [[timeliness>>doc:sdmx:Glossary 2\.1.Timeliness.WebHome]]. [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] standards provide support for all of these aspects of data dissemination. Standard data formats promote ease of use, and provide links to relevant metadata. The concept of registry services means that data and metadata can more easily be discovered. [[Timeliness>>doc:sdmx:Glossary 2\.1.Timeliness.WebHome]] is improved throughout the data lifecycle by increases in efficiency, promoted through the availability of metadata and ease of use.
++In discussions of statistical data, there are many aspects of its dissemination which impact data quality: data discovery, ease of use, and [[timeliness>>doc:sdmx:Glossary 2\.1.Timeliness.WebHome]]. [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] standards provide support for all of these aspects of data dissemination. Standard data formats promote ease of use, and provide links to relevant metadata. The (% style="color:#e74c3c" %)concept(%%) of registry services means that data and metadata can more easily be discovered. [[Timeliness>>doc:sdmx:Glossary 2\.1.Timeliness.WebHome]] is improved throughout the data lifecycle by increases in efficiency, promoted through the availability of metadata and ease of use.
  It is important to note that [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] is primarily focused on the //exchange// and //dissemination// of statistical data and metadata. There may also be many uses for the standard model and formats specified here in the context of internal processing of data that are not concerned with the exchange between organizations and users, however. It is felt that a clear, standard formatting of data and metadata for the purposes of exchange and dissemination can also facilitate internal processing by organizations and users, but this is not the focus of the specification.
@@ -210,28 +210,28 @@
  == 3.4 The SDMX View of Statistical Exchange ==
--Version 1.0 of ISO/TS 17369 [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] covered statistical [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] and the metadata related to the structure of these [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]]. This scope was useful in supporting the different models of statistical exchange ([[bilateral exchange>>doc:sdmx:Glossary 2\.1.Bilateral exchange.WebHome]], gateway exchange, and data-sharing) but was not by itself sufficient to support them completely. Versions 2.0 and 2.1 provide a much more complete view of statistical exchange, so that an open data-sharing model can be fully supported, and other models of exchange can be more completely automated. In order to produce technical standards that will support this increased scope, the [[SDMX Information Model>>doc:sdmx:Glossary 2\.1.SDMX Information Model.WebHome]] provides a broader set of formal objects which describe the actors, processes, and resources within statistical exchanges.
++(% style="color:#e74c3c" %)Version(%%) 1.0 of ISO/TS 17369 [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] covered statistical [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] and the metadata related to the structure of these [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]]. This scope was useful in supporting the different models of statistical exchange ([[bilateral exchange>>doc:sdmx:Glossary 2\.1.Bilateral exchange.WebHome]], gateway exchange, and data-sharing) but was not by itself sufficient to support them completely. (% style="color:#e74c3c" %)Versions(%%) 2.0 and 2.1 provide a much more complete view of statistical exchange, so that an open data-sharing model can be fully supported, and other models of exchange can be more completely automated. In order to produce technical standards that will support this increased scope, the [[SDMX Information Model>>doc:sdmx:Glossary 2\.1.SDMX Information Model.WebHome]] provides a broader set of formal objects which describe the actors, processes, and resources within statistical exchanges.
  It is important to understand the set of formal objects not only in a technical sense, but also in terms of what they represent in the real-world exchange of statistical data and metadata.
--The first version of [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] provided for [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] - specific statistical data reported according to a specific structure, for a specific time range - and for [[data structure definitions>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]] - the metadata which describes the structure of statistical [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]]. These are important objects in statistical exchanges, and are retained and enhanced in the second version of the standards in a backward-compatible form. A related object in statistical exchanges is the "[[data flow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]]" - this supports the concept of data reporting or dissemination on an ongoing basis. "[[Data flows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]]" can be understood as [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] which are not bounded by time. Data structures are owned and maintained by agencies - in a similar fashion, [[data flows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] are owned by [[maintenance agencies>>doc:sdmx:Glossary 2\.1.Maintenance agency.WebHome]].
++The first (% style="color:#e74c3c" %)version(%%) of [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] provided for [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] - specific statistical data reported according to a specific structure, for a specific time range - and for [[data structure definitions>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]] - the metadata which describes the structure of statistical [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]]. These are important objects in statistical exchanges, and are retained and enhanced in the second (% style="color:#e74c3c" %)version(%%) of the standards in a backward-compatible form. A related object in statistical exchanges is the "[[data flow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]]" - this supports the (% style="color:#e74c3c" %)concept(%%) of data reporting or dissemination on an ongoing basis. "[[Data flows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]]" can be understood as [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] which are not bounded by time. Data structures are owned and maintained by agencies - in a similar fashion, [[data flows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] are owned by [[maintenance agencies>>doc:sdmx:Glossary 2\.1.Maintenance agency.WebHome]].
--[[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] allows for the publication of statistical data (and the related [[structural metadata>>doc:sdmx:Glossary 2\.1.Structural metadata.WebHome]]) but also provided for the standard, systematic [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] of [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]]. In version 2.1, [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] were reported independent of the statistical data.
++[[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] allows for the publication of statistical data (and the related [[structural metadata>>doc:sdmx:Glossary 2\.1.Structural metadata.WebHome]]) but also provided for the standard, systematic [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] of [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]]. In (% style="color:#e74c3c" %)version(%%) 2.1, [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] were reported independent of the statistical data.
--However, in 3.0 [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] associated directly with data such as footnotes are reported as [[attributes>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] of the [[data set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]]. For other [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]], principally that linked to structures like “[[concepts>>doc:sdmx:Glossary 2\.1.Concept.WebHome]]”, [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] provides reference "[[metadata sets>>doc:sdmx:Glossary 2\.1.Metadata set.WebHome]]", "[[metadata structure definitions>>doc:sdmx:Glossary 2\.1.Metadata structure definition.WebHome]]", and "[[metadata flows>>doc:sdmx:Glossary 2\.1.Metadataflow.WebHome]]". These objects are very similar to [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]], [[data structure definitions>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]], and [[data flows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]], but concern [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] rather than statistical observations. In the same way that [[data providers>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]] may publish statistical data, they may also publish [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]]. Metadata structural definitions are maintained by agencies in a fashion similar to the way that agencies maintain [[data structure definitions>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]], the structural definitions of [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]].
++However, in 3.0 [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] associated directly with data such as footnotes are reported as [[attributes>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] of the [[data set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]]. For other [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]], principally that linked to structures like “(% style="color:#e74c3c" %)concepts(%%)”, [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] provides reference "[[metadata sets>>doc:sdmx:Glossary 2\.1.Metadata set.WebHome]]", "[[metadata structure definitions>>doc:sdmx:Glossary 2\.1.Metadata structure definition.WebHome]]", and "[[metadata flows>>doc:sdmx:Glossary 2\.1.Metadataflow.WebHome]]". These objects are very similar to [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]], [[data structure definitions>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]], and [[data flows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]], but concern [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] rather than statistical observations. In the same way that [[data providers>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]] may publish statistical data, they may also publish [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]]. Metadata structural definitions are maintained by agencies in a fashion similar to the way that agencies maintain [[data structure definitions>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]], the structural definitions of [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]].
--The structural definitions of both data and [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] associate specific statistical [[concepts>>doc:sdmx:Glossary 2\.1.Concept.WebHome]] with their [[representations>>doc:sdmx:Glossary 2\.1.Representation.WebHome]], whether textual, coded, etc. These [[concepts>>doc:sdmx:Glossary 2\.1.Concept.WebHome]] are taken from a "[[concept scheme>>doc:sdmx:Glossary 2\.1.Concept scheme.WebHome]]" which is maintained by a specific agency. [[Concept schemes>>doc:sdmx:Glossary 2\.1.Concept scheme.WebHome]] group a set of [[concepts>>doc:sdmx:Glossary 2\.1.Concept.WebHome]], provide their definitions and names, and allow for semantic relationships to be expressed, when some [[concepts>>doc:sdmx:Glossary 2\.1.Concept.WebHome]] are specializations of others. It is possible for a single [[concept scheme>>doc:sdmx:Glossary 2\.1.Concept scheme.WebHome]] to be used both for data structures - key families - and for [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] structures.
++The structural definitions of both data and [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] associate specific statistical (% style="color:#e74c3c" %)concepts(%%) with their [[representations>>doc:sdmx:Glossary 2\.1.Representation.WebHome]], whether textual, coded, etc. These (% style="color:#e74c3c" %)concepts(%%) are taken from a "[[concept scheme>>doc:sdmx:Glossary 2\.1.Concept scheme.WebHome]]" which is maintained by a specific agency. [[Concept schemes>>doc:sdmx:Glossary 2\.1.Concept scheme.WebHome]] group a set of (% style="color:#e74c3c" %)concepts(%%), provide their definitions and names, and allow for semantic relationships to be expressed, when some (% style="color:#e74c3c" %)concepts(%%) are specializations of others. It is possible for a single [[concept scheme>>doc:sdmx:Glossary 2\.1.Concept scheme.WebHome]] to be used both for data structures - key families - and for [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] structures.
--Inherent in any statistical exchange – and in many dissemination activities – is a concept of "service level agreement", even if this is not formalized or made explicit. [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] incorporates this idea in objects termed "[[provision agreements>>doc:sdmx:Glossary 2\.1.Provision agreement.WebHome]]". [[Data providers>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]] may provide data to many different [[data flows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]]. [[Data flows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] may incorporate data coming from more than one [[data provider>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]]. [[Provision agreements>>doc:sdmx:Glossary 2\.1.Provision agreement.WebHome]] are the objects which tell you which [[data providers>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]] are supplying what data to which [[data flows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]]. Similarly, metadata [[provision agreements>>doc:sdmx:Glossary 2\.1.Provision agreement.WebHome]] for [[metadata flows>>doc:sdmx:Glossary 2\.1.Metadataflow.WebHome]].
++Inherent in any statistical exchange – and in many dissemination activities – is a (% style="color:#e74c3c" %)concept(%%) of "service (% style="color:#e74c3c" %)level(%%) agreement", even if this is not formalized or made explicit. [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] incorporates this idea in objects termed "[[provision agreements>>doc:sdmx:Glossary 2\.1.Provision agreement.WebHome]]". [[Data providers>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]] may provide data to many different [[data flows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]]. [[Data flows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] may incorporate data coming from more than one [[data provider>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]]. [[Provision agreements>>doc:sdmx:Glossary 2\.1.Provision agreement.WebHome]] are the objects which tell you which [[data providers>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]] are supplying what data to which [[data flows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]]. Similarly, metadata [[provision agreements>>doc:sdmx:Glossary 2\.1.Provision agreement.WebHome]] for [[metadata flows>>doc:sdmx:Glossary 2\.1.Metadataflow.WebHome]].
--[[Provision Agreements>>doc:sdmx:Glossary 2\.1.Provision agreement.WebHome]] allow for data collection restrictions to be applied at the level of the [[Data Provider>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]] in the context of the collection ([[data flow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]]), this set of information is termed a ‘Data Constraint’ in the [[SDMX Information Model>>doc:sdmx:Glossary 2\.1.SDMX Information Model.WebHome]]. Additionally, in a dissemination environment, data can be queried at the level of the [[Provision Agreement>>doc:sdmx:Glossary 2\.1.Provision agreement.WebHome]], this can be a complete [[dataset>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] as supplied by a specific [[Data Provider>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]] for the [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]], a subset of data, or information about what data exists (Data Availability).
++[[Provision Agreements>>doc:sdmx:Glossary 2\.1.Provision agreement.WebHome]] allow for data collection restrictions to be applied at the (% style="color:#e74c3c" %)level(%%) of the [[Data Provider>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]] in the context of the collection ([[data flow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]]), this set of information is termed a ‘Data (% style="color:#e74c3c" %)Constraint(%%)’ in the [[SDMX Information Model>>doc:sdmx:Glossary 2\.1.SDMX Information Model.WebHome]]. Additionally, in a dissemination environment, data can be queried at the (% style="color:#e74c3c" %)level(%%) of the [[Provision Agreement>>doc:sdmx:Glossary 2\.1.Provision agreement.WebHome]], this can be a complete [[dataset>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] as supplied by a specific [[Data Provider>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]] for the [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]], a subset of data, or information about what data exists (Data Availability).
  A brief summary of the objects described in the information model includes:
  * //**[[Data Set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]]:**// Data is organized into discrete sets, which include particular observations for a specific period of time. A [[data set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] can be understood as a collection of similar data, sharing a structure, which covers a fixed period of time.
--* //**[[Data Structure Definition>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]] ([[DSD>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]], also known as Key Family in Version 2.0): **//Each [[data set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] has a set of [[structural metadata>>doc:sdmx:Glossary 2\.1.Structural metadata.WebHome]]. These descriptions are referred to in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] as [[Data Structure Definitions>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]], which include information about how concepts are associated with the [[measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]], [[dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]], and [[attributes>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] of a data “cube,” along with information about the [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] of data and related identifying and descriptive (structural) metadata. In Version 2.1, the term "Key Family" was replaced by "[[Data Structure Definition>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]]" ([[DSD>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]]) both in XML Schemas and the Information Model. The [[DSD>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]] has been modified in version 3.0 to better support microdata by providing the option to define multiple [[measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] and for [[attributes>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] and [[measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] to take arrays of values. An optional reference to a [[Metadata Structure Definition>>doc:sdmx:Glossary 2\.1.Metadata structure definition.WebHome]] has also been added for describing the [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] associated with the data. When reported, these [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] are included as part of the [[dataset>>doc:sdmx:Glossary 2\.1.Data set.WebHome]].
++* //**[[Data Structure Definition>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]] ([[DSD>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]], also known as Key Family in (% style="color:#e74c3c" %)Version(%%) 2.0): **//Each [[data set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] has a set of [[structural metadata>>doc:sdmx:Glossary 2\.1.Structural metadata.WebHome]]. These descriptions are referred to in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] as [[Data Structure Definitions>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]], which include information about how (% style="color:#e74c3c" %)concepts(%%) are associated with the [[measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]], [[dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]], and [[attributes>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] of a data “cube,” along with information about the [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] of data and related identifying and descriptive (structural) metadata. In (% style="color:#e74c3c" %)Version(%%) 2.1, the term "Key Family" was replaced by "[[Data Structure Definition>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]]" ([[DSD>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]]) both in XML Schemas and the Information Model. The [[DSD>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]] has been modified in (% style="color:#e74c3c" %)version(%%) 3.0 to better support microdata by providing the option to define multiple [[measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] and for [[attributes>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] and [[measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] to take arrays of values. An optional reference to a [[Metadata Structure Definition>>doc:sdmx:Glossary 2\.1.Metadata structure definition.WebHome]] has also been added for describing the [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] associated with the data. When reported, these [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] are included as part of the [[dataset>>doc:sdmx:Glossary 2\.1.Data set.WebHome]].
  * //**[[Code list>>doc:sdmx:Glossary 2\.1.Code list.WebHome]]:**// [[Code lists>>doc:sdmx:Glossary 2\.1.Code list.WebHome]] enumerate a set of [[codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] to be used in the [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] of [[dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]], [[attributes>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]], and other structural parts of [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]. [[Codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] can be organised into simple [[hierarchies>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] within a [[code list>>doc:sdmx:Glossary 2\.1.Code list.WebHome]], and more complex [[hierarchies>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] potentially involving multiple [[code lists>>doc:sdmx:Glossary 2\.1.Code list.WebHome]] using [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] and [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] association structures.
--* //**Value list:**// Value lists introduced in version 3.0 are similar to [[codelists>>doc:sdmx:Glossary 2\.1.Code list.WebHome]] with the exception that the items do not need to conform to the usual [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] rules for identifiable objects. That allows the values to include characters such as [[currency>>doc:sdmx:Glossary 2\.1.Currency.WebHome]] symbols (e.g. ¥) which would otherwise make illegal [[codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]]. However, unlike [[codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]], values are not individually identifiable. Value lists find application in concepts and [[data structures definitions>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]] for less structured data and microdata enumerations and can be mapped to other value or [[code lists>>doc:sdmx:Glossary 2\.1.Code list.WebHome]] using [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] maps.
++* //**Value list:**// Value lists introduced in (% style="color:#e74c3c" %)version(%%) 3.0 are similar to [[codelists>>doc:sdmx:Glossary 2\.1.Code list.WebHome]] with the exception that the items do not need to conform to the usual [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] rules for identifiable objects. That allows the values to include characters such as [[currency>>doc:sdmx:Glossary 2\.1.Currency.WebHome]] symbols (e.g. ¥) which would otherwise make illegal [[codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]]. However, unlike [[codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]], values are not individually identifiable. Value lists find application in (% style="color:#e74c3c" %)concepts(%%) and [[data structures definitions>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]] for less structured data and microdata enumerations and can be (% style="color:#e74c3c" %)mapped(%%) to other value or [[code lists>>doc:sdmx:Glossary 2\.1.Code list.WebHome]] using [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] (% style="color:#e74c3c" %)maps(%%).
  * //**Organisation Scheme:**// Organisations and organisation structure can be defined in an Organisation Scheme. Specific Organisation Schemes exist for [[Maintenance Agency>>doc:sdmx:Glossary 2\.1.Maintenance agency.WebHome]], [[Data Provider>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]], Metadata Provider, [[Data Consumer>>doc:sdmx:Glossary 2\.1.Data consumer.WebHome]], and Organisation [[Unit>>doc:sdmx:Glossary 2\.1.Statistical unit.WebHome]].
  * //**[[Category Scheme>>doc:sdmx:Glossary 2\.1.Category scheme.WebHome]] and [[Categorisation>>doc:sdmx:Glossary 2\.1.Categorisation.WebHome]]:**// [[Category schemes>>doc:sdmx:Glossary 2\.1.Category scheme.WebHome]] are made up of a [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] of [[categories>>doc:sdmx:Glossary 2\.1.Category.WebHome]], which in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] may include any type of useful [[classification>>doc:sdmx:Glossary 2\.1.Statistical Classification.WebHome]] for the organization of data and metadata. A [[Categorisation>>doc:sdmx:Glossary 2\.1.Categorisation.WebHome]] links a [[category>>doc:sdmx:Glossary 2\.1.Category.WebHome]] to an identifiable object. In this way sets of objects can be categorised. A statistical subjectmatter domain scheme is implemented in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] as a [[Category Scheme>>doc:sdmx:Glossary 2\.1.Category scheme.WebHome]].
  * //**[[Concept Scheme>>doc:sdmx:Glossary 2\.1.Concept scheme.WebHome]]:**// A [[concept scheme>>doc:sdmx:Glossary 2\.1.Concept scheme.WebHome]] is a maintained list of (% style="color:#e74c3c" %)concepts(%%) that are used in [[data structure definitions>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]] and [[metadata structure definitions>>doc:sdmx:Glossary 2\.1.Metadata structure definition.WebHome]]. There can be many such [[concept schemes>>doc:sdmx:Glossary 2\.1.Concept scheme.WebHome]]. A “core” [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] of the (% style="color:#e74c3c" %)concept(%%) can be specified (e.g. a core [[code list>>doc:sdmx:Glossary 2\.1.Code list.WebHome]], or other [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] such as “date”). Note that this core [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] can be overridden in the [[data structure definition>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]] or [[metadata structure definition>>doc:sdmx:Glossary 2\.1.Metadata structure definition.WebHome]] that uses the (% style="color:#e74c3c" %)concept(%%). Indeed, organisations wishing to remain with (% style="color:#e74c3c" %)version(%%) 1.0 key family schema specifications will continue to declare the [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] in the key family definition.