A hearing device has an adjustable transfer function comprising M≧1 sub-functions (M is an integer). A method for operating the hearing device includes deriving input audio signals from a current acoustic environment. For each of the M sub-functions, derive, based on the input audio signals and for each class of N≧2 classes that describe a predetermined acoustic environment, a class similarity factor indicative of the similarity of the current acoustic environment with the predetermined acoustic environment described by the respective class (N is an integer). Derive from N predetermined base parameter sets assigned to the respective sub-function and in dependence of the class similarity factors, an activity parameter set for the respective sub-function. Each of the N base parameter sets assigned to the respective sub-function is assigned to a different class of the N classes. Adjust the respective sub-function by means of the activity parameter set.