A non-transitory computer readable medium storing instructions that, when executed by a processor, cause the processor to identify two or more similar items within a local catalogue, by performing the steps of:
- generating, at a web server computing system, a web application interface that includes a plurality of interface elements, wherein each interface element included in the plurality of interface elements is individually selectable when the web application interface is displayed;
- identifying, at the web server computing system, a different digital content item for each interface element included in the plurality of interface elements, wherein a given digital content item identified for a first interface element included in the plurality of interface elements is identified by:
- determining that the web application interface is to be presented to a user that has interacted with a previously-presented digital content item included in a local catalogue,
- determining a set of global counts based on interaction data associated with a global group of users, wherein a first global count in the set of global counts indicates a number of times the global group of users has interacted with a first digital content item in a global catalogue, and a second global count in the set of global counts indicates a number of times the global group of users has interacted with a second digital content item in the global catalogue after interacting with the first digital content item, the global group of users interacting with the first and second digital content items via web content browsers interacting with the web server computing system through a network, wherein the set of global counts is stored to a first section of an interaction history database,
- determining a set of local counts based on interaction data associated with a local group of users, wherein a first local count in the set of local counts indicates a number of times the local group of users has interacted with the previously-presented digital content item, and a second local count in the set of local counts indicates a number of times the local group of users has interacted with the given digital content item in the local catalogue after interacting with the previously-presented digital content item, and wherein the previously-presented digital content item corresponds to the first digital content item and the given digital content item corresponds to the second digital content item, and wherein the set of local counts is stored to a second section of the interaction history database,
- combining the set of global counts and the set of local counts to compute an interaction probability that indicates the likelihood of a particular user within the local group of users interacting with the given digital content item after interacting with the previously-presented digital content item,
- computing a similarity score that indicates the similarity between the previously-presented digital content item and the given digital content item based on the interaction probability and a popularity score associated with the given digital content item, and
- selecting the given digital content item for presentation in the first interface element based on the similarity score;
- and
- transmitting, by the web server computing system to a content browser associated with the user, the web application interface that presents the given digital content item within the first interface element, wherein one or more interactions with the first interface element captured by the content browser are transmitted over the network to the web server computing system and recorded within the second section of the interaction history database.