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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 labeled 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 relationships. Based on the SKOS formalization, these concepts are related but the type of relationship is not specified.

The tree of concepts can be managed in the left panel of the Resources tab of the project dashboard.

Expand and collapse tree nodes

To expand and collapse tree nodes to show and hide narrower concepts:

  • Select the right arrow to the left of a node to expand the list of child nodes and the down arrow to collapse it.

Or:

  • Hover over the concept and select Expand node or Collapse node to the right of the concept label.

To expand and collapse all the tree, hover over Thesaurus and select Expand node or Collapse node to the right.

Find concepts in the tree

To find concepts in the taxonomy tree, enter the string in the search box and press Enter.
To toggle the search parameter menu, select the gear icon to the right of it. The Search settings window will appear.

  • In the Search by area, select URI or Label to match the string you type with concepts' URIs or labels.
  • If you choose Label, you can then select which labels—preferred, alternative, hidden—to match in the Labels area. Multiple selection is allowed.
  • In the Match type area you can select the match criteria, that is where in the label (or URL) the string you type will be searched for. Based on the criteria, the labels or URIs must:

    • Exact match: be exactly equal to the typed string.
    • Starts match: start with the typed string.
    • Ends match: end with the typed string.
    • By word: contain one or more words that exactly match the typed string.
    • Starts by word: contain one or more words that start with the typed string.
    • End by word: contain one or more words that end with the typed string.
    • Any: contain the typed string, no matter where.
  • Select the language (multiple selection is allowed) in the Languages area (available in multi-language projects).

Warning

To use the parameters included in the following areas:

  • Search by
  • Match type
  • Labels
  • Languages

the search bar must not be empty. The other parameters in the other areas described below can also be applied with an empty search bar.

  • In the Extraction area, filter your search based on the concept extraction.
  • In the Extraction method area, filter your search based on the extraction method.
  • In the Approval status area, filter your search based on the concept validation.

In multi-language projects, when you want to match labels, you can also select one or more languages so to match only the labels of those languages. No selection means any language.

Search results are shown below the search bar and contain the basic information for each concept.

Select a concept in the list of results to open it in the Edit Concept panel.

To cancel the search select the X icon in the search box.

Add concepts

The New concept dialog

Whenever you create new concepts from scratch 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 drop-down 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 Create concept

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 .

In any case, the New concept dialog appears, use it as described above 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 a label 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 relationship between concepts.

    Or:

    Select Creare new "label" or press Enter to create a new concept with the label you typed.

    In case of a new concept, the New concept dialog appears, allowing you to set a broader concept for the new concept (see above) and complete its creation.

Add concepts using suggestions

It is possible to add concepts from the Most Relevant Terms panel. To show it:

  1. Select Toggle most relevant terms on the toolbar above the thesaurus tree. Within this panel, you can:

    • Use the search bar to look for specific concepts.
    • Sort the concept list alphabetically.
  2. Drag and drop the concept (multiple selection is allowed) in the position of your interest within the tree, specifically:

    • Below Thesaurus to create a broader concept.

    Or:

    • Below an existing concept to create a narrower concept.

To hide the Most Relevant Terms panel, select Toggle most relevant terms .

You can use automatic suggestions to define new concepts, read the next article 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:

to know how to add concepts using other thesauri.

Edit concepts

Read the articles in the section devoted to the topic to learn how to edit concepts and their relations with other concepts.

Move concepts

To move a concept node within the tree, drag it to its new position.

Delete concepts

Warning

When you delete a concept, all narrower concepts (children nodes) are deleted too.

Delete a concept in the Resources panel

  1. Select the concept in the Resources panel, then select Delete concept .
  2. Select Delete to confirm.

Or:

  1. Hover over the concept in the Resources panel, then select Delete concept .
  2. Select Delete to confirm.

Or:

  1. Select the concept in the Resources panel.
  2. Select Delete concept on the Edit Concept panel toolbar.
  3. Select Delete to confirm.
  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 to delete under BROADER CONCEPTS , NARROWER CONCEPTS or RELATED CONCEPTS then select the X icon .

Delete multiple concepts

To delete multiple concepts:

  1. Press and hold Ctrl then click the concepts to delete inside the Resources panel.
  2. Select Delete concepts .
  3. Select Delete to confirm.