The plan of this proposal is as follows. Section 1 introduces what an ordinal variable is, and gives the history of the analysis of ordinal response variables. Section 2 describes one of the most popular models for ordinal response variable, namely the proportional odds models. Section 3 introduces the ordered stereotype model, which is the model this work is focused on. The principal novel content of this PhD project is presented in Section 4, the partial ordered stereotype model. Sections 5 and 6 illustrate the methodology explained in Sections 3 and 4 by means of an example with real data and a simulation study respectively. Finally, in Sections 7 and 8 we outline the direction of future research as well as presenting a tentative timetable for the completion of the PhD.