A multinomial model of the "Who said what?" paradigm (S. E. Taylor, S. T. F
iske, N. J. Etcoff, & A. J. Ruderman, 1978) explains the pattern of partici
pants' assignment errors by means of the joint operation of several process
es. Specifically, memory for discussion statements, person memory, category
memory and 3 different guessing processes can be accommodated by the model
. The model's ability to disentangle these processes is validated in a seri
es of 5 experiments. The model thereby enables a more refined use of the "W
ho Said what?" paradigm in resting theories of social categorization. This
is demonstrated in a 6th experiment in which the validated model is applied
to the study of the effects of cognitive load on categorization.