Expansion Rules are one of the advanced options available in the Taxonomy creation process which helps expand the possibilities of variations for a Taxonomy and save time for the user. We assume you already know how to create a Taxonomy, if not you can check out this Tutorial on Taxonomy.
Adding more specific variations to a Taxonomy gets more hits for a Taxonomy and thereby more signals (data). Hence these rules add better variation options and save time in adding them individually. For example, if you want to create variations for Apple Inc, you will start with adding Apple, APPLE, apple, $AAPL and so on. Instead of creating all those, you can simply add a few expansion rules which will create lowercase, uppercase, titlecase, add a prefix etc. to just one variation of your Taxonomy.
This option is available for all types of Taxonomies except for 'Themes' since the Taxonomy extraction workflow is case insensitive to variations added for a Theme. The variations created through these rules won't be seen in the UI but will be a part of the variation query in the extraction process.
Now let's move on to adding an expansion rule.
How can you add an Expansion Rule?
When creating a new Taxonomy or editing an existing one, you will find Expansion Rules Editor under Advanced Options. Click on “Open Editor” for expansion rules and it will open a new dialog box. Select the rules from the drop-down, add the values if required for specific rules and press enter and then click on the checkbox for each fields to which the rules should apply. Click on “Add Rule” and then “Save”. You can add more than one rule for a Taxonomy.
In case you want to edit a rule, you can click on the Edit icon, make changes to the rule and click on "Update Rule" and then "Save".
Below are the list of rules and their conditions:
Upcase: will expand your values in any required field in Uppercase ( For ex: Apple , Tesla ---> APPLE, TESLA ). At least one field should be selected by clicking on the checkbox for the rule to be applied.
Downcase: will expand your values in any required field in Lowercase ( For ex: Apple, Tesla ---> apple, tesla ). At least one field should be selected by clicking on the checkbox for the rule to be applied.
Titlecase: will expand your values in any required field in Titlecase ( For ex: apple, tesla ---> Apple, Tesla). At least one field should be selected by clicking on the checkbox for the rule to be applied.
Prefix: will expand your values in any required field with a value added in the beginning. At least one field should be selected by clicking on the checkbox and at least one value should be entered for the rule to be applied.
For ex: If you want to add a dollar sign ($) or hashtag (#) as prefix for Ticker (AAPL) and Name (Apple), then add "$" or "#" as the value and click on enter. Then select the fields Ticker and Name by clicking on the checkbox. The resulting variations will be $AAPL , #AAPL , $Apple, #Apple.
Suffix: will expand your values in any required field with a value added to the end. At least one field should be selected by clicking on the checkbox and at least one value should be entered for the rule to be applied.
For ex: If you want to add a dollar sign (@) or hashtag (!) as suffix for Ticker (AAPL), then add "@" or "!" as the value and click on enter. Then select the field Ticker by clicking on the checkbox. The resulting variations will be [email protected] , AAPL! .
Surround Case: will expand your values in any required field with a value added to the beginning and end. At least one field should be selected by clicking on the checkbox and at least one value should be entered for the rule to be applied.
For ex: If selected field is Ticker and value is "#". The resulting variations will be #Ticker#
Note: If two characters are added together then the first character will be at the beginning of the variation and second character at the end i.e., If selected field is Ticker and values are "(" and ")" , then the resulting variations will be (Ticker).
Field Combination: will expand your values in any required field with a separator value added between the two fields selected. At least two fields should be selected by clicking on the checkbox and at least one separator value should be entered for the rule to be applied.
For ex: If selected fields are Exchange and Ticker and separator value is ":" , then the resulting variations will be "Exchange:Ticker" and "Ticker:Exchange".