HED specification
3.3.0

Contents:

  • 1. Introduction to HED
    • 1.1. Scope of HED
    • 1.2. Brief history of HED
    • 1.2. Goals of HED
    • 1.3. HED design principles
    • 1.4. Specification organization
  • 2. HED terminology
    • 2.1 Definitions
      • Agent [*]
      • Condition-variable [*]
      • Control-variable [*]
      • Dataset
      • Event [*]
      • Event-context [*]
      • Event marker
      • Event-stream [*]
      • Experiment-participant [*]
      • Experimental-trial [*]
      • HED schema [*]
      • HED string
      • HED tag
      • Indicator-variable [*]
      • Parameter [*]
      • Recording [*]
      • Tag-group
      • Task [*]
      • Temporal scope
      • Time-block [*]
    • 2.2 Character sets and restrictions
  • 3. HED formats
    • 3.1. Schema formats
      • 3.1.1. Official schema releases
      • 3.1.2. Schema layout overview
        • 3.1.2.1. The header
        • 3.1.2.2. The prologue
        • 3.1.2.3. The schema section
        • 3.1.2.4. Unit classes and units
        • 3.1.2.5. Unit modifiers
        • 3.1.2.6. Value classes
        • 3.1.2.7. Schema attributes
        • 3.1.2.8. Schema properties
        • 3.1.2.9. The epilogue
      • 3.1.3. Naming conventions
        • 3.1.3.1. Node elements
        • 3.1.3.2. Epilogue and prologue
        • 3.1.3.3. Naming in other blocks
      • 3.1.4. MediaWiki schema format
      • 3.1.5. XML schema format
    • 3.2. Annotation formats
      • 3.2.1. Vocabulary organization
      • 3.2.2. Tag forms
      • 3.2.3. Tag case-sensitivity
      • 3.2.4. Tags that take values
      • 3.2.5. Tag extensions
      • 3.2.6. Tag namespace prefixes
      • 3.2.7. Strings and groups
        • 3.2.7.1. Parenthesis and order
        • 3.2.7.2. Tag group attributes
        • 3.2.7.3. Empty tags and groups
        • 3.2.7.4. Repeated expressions
      • 3.2.8. Special tags
        • 3.2.8.1. The Definition tag
        • 3.2.8.2. Def and Def-expand tags
        • 3.2.8.3. Onset, Offset, and Inset
        • 3.2.8.4. Duration and Delay
        • 3.2.8.5. The Event-context tag
      • 3.2.9. Sidecars
        • 3.2.9.1. Sidecar entries
        • 3.2.9.2. Sidecar validation
        • 3.2.9.3. Sidecar curly braces
        • 3.2.9.4. A sidecar example
      • 3.2.10. Tabular files
        • 3.2.10.1 Tabular types
        • 3.2.10.2. Tabular annotations
        • 3.2.10.3. Event-level processing
        • 3.2.10.4. File-level processing
    • 3.3. Semantic versioning
  • 4. Basic annotation
    • 4.1. Instantaneous events
    • 4.2. Sensory presentations
    • 4.3. Task role
    • 4.4. Agent actions
    • 4.5. Experimental control
    • 4.6. Data features
    • 4.7. What else?
  • 5. Advanced annotation
    • 5.1. Creating definitions
    • 5.2. Using definitions
      • 5.2.1. The Def tag
      • 5.2.2. The Def-expand tag
    • 5.3. Temporal scope
      • 5.3.1. Using Onset and Offset
      • 5.3.2. Using Inset
      • 5.3.3. Using Duration
      • 5.3.4. Using Delay
    • 5.4. Event streams
    • 5.5. Event contexts
    • 5.6. Experimental design
    • 5.7. Specialized annotation
      • 5.7.1. Parameter tags
  • 6. Infrastructure and tools
    • 6.1. Basic tag handling
      • 6.1.1. Tag forms
      • 6.1.2. Parentheses and commas
      • 6.1.3. Tag ordering
      • 6.1.4. Definitions
    • 6.2. File-level handling
    • 6.3. HED support of BIDS
      • 6.3.1. BIDS tabular files
      • 6.3.2. BIDS timeseries
      • 6.3.3. BIDS sidecars
      • 6.3.4. Annotation assembly
      • 6.3.5. HED version in BIDS
      • 6.3.6. HED in the BIDS validator
      • 6.3.7. HED python tools
  • 7. Library schemas
    • 7.1. Why library schemas?
    • 7.2. Standalone schemas
    • 7.3. Partnered schemas
      • 7.3.1. Partnered files
      • 7.3.2. Partnered formats
      • 7.3.3. Auxiliary sections
      • 7.3.4. Partnered attributes
      • 7.2.5. Motivation for partners
        • 7.3.5.1. Auxiliary consistency
        • 7.3.5.2. Reserved tag handling
        • 7.3.5.3. Annotation conciseness
        • 7.3.5.4. Library searches
        • 7.3.5.5. Suggested tags
        • 7.3.6 Lazy partnering
    • 7.4. Library schema design
      • 7.4.1. General design rules
      • 7.4.2. Standalone design rules
      • 7.4.3. Partnered design rules
      • 7.4.4. Schema namespaces
    • 7.5. Library schemas in BIDS
  • 8. The HED ontology
    • 8.1. HED views and representations
      • 8.1.1. The annotator’s view
      • 8.1.2. The ontologist’s view
      • 8.1.3. HED information space
      • 8.1.4. HED representations
        • 8.1.4.1. The MediaWiki format
        • 8.1.4.2. Spreadsheet files
        • 8.1.4.3. Spreadsheet format
        • 8.1.4.4. Spreadsheet <–> MediaWiki
        • 8.1.4.5. Tag spreadsheet <–> Ontology
    • 8.2. HED schema to ontology
      • 8.2.1. Overall ontology structure
      • 8.2.2. HED Tags
        • 8.2.2.1. MediaWiki tag format
        • 8.2.2.2. XML tag format
        • 8.2.2.3. OWL format for HED classes
      • 8.2.3. Schema attributes
        • 8.2.3.1. Attribute ontology types
        • 8.2.3.2. Schema attribute properties
        • 8.2.3.3. Attribute representation
        • 8.2.3.4. MediaWiki attribute format
        • 8.2.3.5. XML attribute format
        • 8.2.3.6. OWL format for attributes.
      • 8.2.4 Other auxiliary sections
    • 8.3. HED global identifiers
      • 8.3.1. Schema identifiers
      • 8.3.2. Ontology namespace
      • 8.3.3. HED IRIs
  • A. Schema format details
    • A.1. Auxiliary schema sections
      • A.1.1. Unit classes and units
      • A.1.2. Unit modifiers
      • A.1.3. Value classes
      • A.1.4. Schema attributes
        • A.1.4.1. allowedCharacter
        • A.1.4.2. conversionFactor
        • A.1.4.3. defaultUnits
        • A.1.4.4. deprecatedFrom
        • A.1.4.5. extensionAllowed
        • A.1.4.6. hedId
        • A.1.4.7. inLibrary
        • A.1.4.8. relatedTag
        • A.1.4.9. requireChild
        • A.1.4.10. reserved
        • A.1.4.11. rooted
        • A.1.4.12. SIUnit
        • A.1.4.13. SIUnitModifier
        • A.1.4.14. SIUnitSymbolModifier
        • A.1.4.15. suggestedTag
        • A.1.4.16. tagGroup
        • A.1.4.17. takesValue
        • A.1.4.18. topLevelTagGroup
        • A.1.4.19. unique
        • A.1.4.20. unitClass
        • A.1.4.21. unitPrefix
        • A.1.4.22. unitSymbol
        • A.1.4.23. valueClass
        • A.1.4.x. Deprecated attributes
      • A.1.5. Schema properties
    • A.2. MediaWiki file format
      • A.2.1. Overall file layout
      • A.2.2. MediaWiki header
      • A.2.3. MediaWiki prologue and epilogue
      • A.2.4. MediaWiki schema section
      • A.2.5. MediaWiki auxiliary sections
        • A.2.5.1. Unit classes and units
        • A.2.5.2. Unit modifiers
        • A.2.5.3. Value classes
        • A.2.5.4. Schema attributes
        • A.2.5.5. Schema properties
    • A.3. XML file format
      • A.3.1. XML file layout
      • A.3.2. XML header
      • A.3.3. XML prologue and epilogue
      • A.3.4. XML schema section
      • A.3.5. XML auxiliary sections
        • A.3.5.1. Unit classes
        • A.3.5.2. Unit modifiers
        • A.3.5.3 Value classes
        • A.3.5.4. Schema attributes
        • A.3.5.5. Schema properties
  • B. HED errors
    • B.1. HED validation errors
      • CHARACTER_INVALID
      • COMMA_MISSING
      • DEF_EXPAND_INVALID
      • DEF_INVALID
      • DEFINITION_INVALID
      • ELEMENT_DEPRECATED*
      • PARENTHESES_MISMATCH
      • PLACEHOLDER_INVALID
      • REQUIRED_TAG_MISSING
      • SCHEMA_LOAD_FAILED
      • SIDECAR_BRACES_INVALID
      • SIDECAR_INVALID
      • SIDECAR_KEY_MISSING*
      • STYLE_WARNING*
      • TAG_EMPTY
      • TAG_EXPRESSION_REPEATED
      • TAG_EXTENDED*
      • TAG_EXTENSION_INVALID
      • TAG_GROUP_ERROR
      • TAG_INVALID
      • TAG_NAMESPACE_PREFIX_INVALID
      • TAG_NOT_UNIQUE
      • TAG_REQUIRES_CHILD
      • TEMPORAL_TAG_ERROR
      • TILDES_UNSUPPORTED
      • UNITS_INVALID
      • UNITS_MISSING*
      • VALUE_INVALID
      • VERSION_DEPRECATED*
    • B.2. Schema validation errors
      • B.2.1. General validation errors
        • SCHEMA_ATTRIBUTE_INVALID
        • SCHEMA_ATTRIBUTE_VALUE_INVALID
        • SCHEMA_CHARACTER_INVALID
        • SCHEMA_DEPRECATION_ERROR
        • SCHEMA_DUPLICATE_NODE
        • SCHEMA_HEADER_INVALID
        • SCHEMA_LIBRARY_INVALID
        • SCHEMA_SECTION_MISSING
        • SCHEMA_VERSION_INVALID
      • B.2.3. MediaWiki format errors
        • WIKI_DELIMITERS_INVALID
        • WIKI_LINE_START_INVALID
        • WIKI_SEPARATOR_INVALID
      • B.2.4. XML format errors
        • XML_SYNTAX_INVALID
      • B.2.5 Schema loading errors
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