Taxonomy basics

A tree of concepts

In a thesaurus project, the taxonomy is visualized as a tree whose nodes represent concepts.

The tree hierarchical structure corresponds to the narrower/broader relation between concepts: if you look at the relation from a node to its children, the child nodes are narrower concepts, if you look at the relation the other way, from child to parent, the parent node is a broader concept.

First-level nodes don't have parent nodes. so they are considered children of the tree root which is conventionally labelled Thesaurus.

The same concept can appear in several locations of the tree: it can have more than one broader concepts and so be the child of more than one node.

The concepts of a thesaurus can also be related to each other in non-hierarchical relations. According to the SKOS formalization, these concepts are related but the type of relation is not specified. This kind of relation is not displayed in the tree visualization.

The tree of concepts is displayed in the Resources panel of the Resources tab of the project dashboard. In the tree, a node's label is the preferred label of the corresponding concept for the favorite project language.

Expand and collapse tree nodes

• To toggle the display of direct child nodes use the right arrow and the down arrow to the left of the parent node.

• To toggle the display of the fully expanded subtree, hover over the concept node and select Expand node or Collapse node .

Find concepts

To find concepts of interest and filter the list accordingly use the search box above the list.

To filter the list so that it only shows concepts whose labels or URIs match a text expression, type the expression and press Enter.

To clear the filter select the X icon in the search box.

To filter on concept properties or adjust how any text expression typed in the search box matches textual properties, open the search settings panel by selecting Advanced Search Settings on the right of the search box.

• To apply any changes select Apply.
• To reset the filter select Reset filters.

These are the settings, divided between the tabs listed on the left of the panel:

• General

  • Search by: this setting is enabled if some textual expression has been typed in the search box.

    • Label: the possible textual expression you typed in the search box is matched against concepts' labels.
    • URI: the possible textual expression you typed in the search box is matched against concepts' URI.

  • Labels: this setting is enabled if some textual expression has been typed in the search box and Search by is set to Label.

    • Preferred label: the possible textual expression you typed in the search box is matched against concepts' preferred labels.
    • Alternative label: the possible textual expression you typed in the search box is matched against concepts' alternative labels.
    • Other label: the possible textual expression you typed in the search box is matched against possible labels of the concept which are neither preferred nor alternative.

  • Match type: this setting is enabled if some textual expression has been typed in the search box. It affects the way the textual expression is matched against le labels of the URIs of the concept, based on the value of Search by.

    Labels or URIs must:

    • Exact match: be exactly equal to the textual expression.
    • Starts match: start with the textual expression.
    • Ends match: end with the textual expression.
    • By word: contain one or more words that exactly match the textual expression.
    • Starts by word: contain one or more words that start with the textual expression.
    • End by word: contain one or more words that end with the textual expression.
    • Any: contain the textual expression, no matter where.

  • Approval status: filter concepts based on their approval status

  • Languages: this setting is enabled for multi-language projects if some textual expression has been typed in the search box and Search by is set to Label.
    Check the languages of the labels to match, multiple selection is allowed. By default, labels in any language are matched.

• Extraction

  • Extraction: filter concepts based on them being marked as to be extracted by models or not. The Any value means no constraint.
  • Extraction method: filter concepts based on their extraction method.
  • Kill list: filter concepts based on the presence or absence of kill lists. The Any value means no constraint.
  • Advanced rules: filter concepts based on the presence or absence of advanced extraction rules. The Any value means no constraint.

• Relations

  This tab contains filters on the presence or absence of basic or advanced relations. The Any value means no constraint.

• Documentation properties

  This tab contains filters on the presence or absence of documentation properties. The Any value means no constraint.

• Custom properties

  This tab contains filters on the presence or absence of custom properties. The Any value means no constraint.

• Custom relations

  This tab contains filters on the presence or absence of custom relations. The Any value means no constraint.

Add concepts

The New concept dialog

Whenever you create new concepts from scratch (see below) the New concept dialog appears.

In the Concepts field you will find any label already typed before opening the dialog. If the field is empty:

1. Type a label and press Enter.
2. Repeat to create more concepts at once.

The specified labels will be considered the preferred labels of the new concepts.

In the Broader concept field you can specify a broader concept for the new concepts.
If you do, the new concepts will be displayed as child nodes of the indicated concept in the taxonomy tree, otherwise the new concepts will be displayed under the root of the tree, they will not have a parent node.
If the field is empty, to specify the broader concept start typing, Concepts with matching labels are displayed in a dropdown list and you can choose the broader concept from it.

If you select View concept, the new concept (or the one corresponding to the first label, in case of multiple concepts) becomes the current concept shown in the Edit concept panel

To confirm the creation of the new concept select Create. To cancel the operation click anywhere outside the dialog.

Add concepts from the Resources panel

To create a first-level concept under the root of the tree:

• Select the plus icon on the toolbar of the Resources panel.

Or:

• Hover over Thesaurus and select Create concept .

To create narrower concepts for an existing concept:

• Select the broader concept or hover over it and choose Create concept .

Use the New concept dialog to define the new concept.

Add concepts from the Edit concept panel

1. Select a concept in the tree of the Resources panel.
2. Select the Relations tab inside the Edit concept panel.

3. Select the plus button under:

   • BROADER CONCEPTS if you want to create a broader concept, that will be displayed as a parent node in the tree.
   • NARROWER CONCEPTS if you want to create a narrower concept, that will be displayed as a child node.
   • RELATED CONCEPTS if you want to create a non-hierarchically related concept, that will be displayed in the tree as you'll decide later.

   The Find concept field appears.

4. Type in the Find concept field. Existing concepts with matching labels are listed below while you type.

5. Choose an existing concept from the list to create a relation between concepts.

   Or:

   Select Create new "label" or press Enter to create a new concept with the label you typed. Use the New concept dialog to define the new concept.

Add concepts using suggestions

You can use automatic suggestions to define new concepts, read the article dedicated to this topic to learn how.

Add concepts during annotation

Read the article about annotating expected results to learn about adding concepts during annotation.

Add concepts from knowledge sources and other projects

Read the articles about:

• Linking knowledge sources
• Linking other projects

to know how to add concepts using other thesauri.

Edit concepts

Select a concept in the taxonomy to edit it in the Edit concept panel.

Move concepts

To move a concept node within the tree, drag it over its new parent concept.
Moving a concept changes one&mdah;possibly the only—broader-narrower relation of the concept, but doesn't affect other relations.

Delete concepts

Warning

When you delete a concept, all the subtree gets deleted. If what you want is to break the link between two concepts without deleting concepts, you have to delete relations.

To delete a concept:

• Select the concept in the Resources panel, then select Delete concept .

Or:

• Hover over the concept in the Resources panel, then select Delete concept .

Or:

1. Select the concept in the Resources panel.
2. Select Delete concept on the Edit concept panel toolbar.

To delete multiple concepts at once:

1. Ctrl+Click inside the Resources panel to select the concepts to delete.
2. Select Delete concepts in the central part of the page.

Delete relations

Info

Deleting a relation between two concepts doesn't delete any concept or any other relation. If you delete the only broader-narrower relation between two concepts, the ex narrower concept becomes a child of the root concept of the tree.

1. In the Resources panel select a concept that is related to the concept to delete.
2. Select the Relations tab of the Edit concept panel.
3. Hover over the concept for which you want to delete the relation under BROADER CONCEPTS , NARROWER CONCEPTS or RELATED CONCEPTS then select the X icon .