Fitting agent with hearing device user model initialization

A fitting system includes one or more processors configured to: initialize a user model; obtain a test setting comprising a primary test setting and a secondary test setting; output the primary test setting and the secondary test setting for presentation to a user; obtain a user input for a preferred test setting indicative of a preference for either the primary test setting or the secondary test setting; and update the user model based on a hearing device parameter of the preferred test setting; wherein the one or more processors are configured to initialize the user model by: obtaining a profile of the user; obtaining a group of reference users; obtaining reference posteriors of reference users in the group of reference users; determining a collaborative user preference distribution based on the reference posteriors; setting the collaborative user preference distribution as a prior; and initializing the user model based on the prior.