Product Taxonomy

Definition

A product taxonomy is the hierarchy of categories used to organise products, from broad departments down to narrow leaf categories. Each platform has its own, it changes over time, and a product can sit in several branches, so a category is meaningful only together with its source and version.

In plain terms

Categories are the basis of most comparisons: “rank within category”, “share of category”. But a category is not a universal fact. Two platforms name and nest things differently, and a platform may reorganise its tree, moving whole branches. Leaf categories also differ enormously in size.

Store the category identifier and the tree’s version rather than the name, and treat the tree as a Slowly Changing Dimension. Public taxonomies such as Google’s product taxonomy and GS1’s Global Product Classification can serve as a neutral reference for mapping.

Example

“Coffee Makers” sits under Kitchen until a March restructure moves it under Appliances.

Read naively, Kitchen sales fell 20%. Nothing happened to demand; a branch moved. Comparing like with like needs the old tree applied to the new months, or the new tree to the old.

Common misunderstandings

• “A category name is a stable key.” Names change and repeat; use identifiers with versions.
• “The same name on two platforms means the same category.” Scope and nesting differ.
• “Leaf categories are all comparable in size.” Some hold a handful of products, others hundreds of thousands.