Does Your Website Suffer From Over-Categorization?

Aug 18, 2016


One of the most common website product categorization issues is over-categorization. Most often this occurs because of an incorrect implementation of a filtering attributes as categories. While categories and filters work in similar ways, they are not interchangeable elements and each has their place in search and browse navigation. Let's break it down.

Categories vs Filters

  • Categories — Typically each category/subcategory will have it's own page, a set of filters specific to the page and a user can select one category at a time, for example "beds" vs ' bedding." For example, "thread count" might be a navigation option on the "bedding" page but not on the "beds" page. Categories represent the hierarchy of the site, the product catalog and they control the features available for browsing those products - including filters.
  • Filters — Navigation options used to adjust and narrow down the product list within a category (or set of search results). Filtering values are not mutually exclusive and allow users to combine multiple filter values to narrow down the product list. For example, within the "bedding" category, a user might combine multiple filters, such as "thread count," "color: green," material: silk," and "size: king" to find the product that best meets their needs.
What is Over-Categorization?
Over-categorization happens when a site's category hierarchy has become too deep and product types and attributes have been mistakenly implemented as categories instead of filters. Over-categorization makes it difficult, if not impossible, for a user to select and see products matching multiple values within that product type or attribute.

Here's an example: If you manage a site that sells cameras and you notice that "point and click" is a popular navigation option and/or you have a large assortment of point and click cameras, it could be tempting to implement the product type as a "category."
The problem is that now point and click cameras have been siloed into an overly narrow category scope. For example, users might see only "fun & basic" point and shoot cameras, even if they are interested in other types of compact cameras.

This can lead to visitor frustration, site abandonment, and a loss of revenue.

The Shared Attribute Test
In general it's clear that the majority of product attributes should be implemented as filters, e.g. product types and, in particular, sub-product types. It can sometimes be difficult to correctly choose between a category or a filter.

The trick is to apply the "shared attribute test." Look at the potential benefits of turning a product type into a categories rather than filters. In a nutshell, if the product attributes are the same across the different product types in question, they should typically be implemented as filters, not as categories.

Oftentimes important product types and attributes are incorrectly implemented as categories because the website design provides more exposure to categories than filters. The underlying intent behind this kind of implementation is good, but in reality it limits a visitor's ability to have full visibility into your product assortment.