This paper introduces the Bradley-Terry regression trunk model, a novel probabilistic approach for the analysis of preference data expressed through paired comparison rankings. In some cases, it... Show moreThis paper introduces the Bradley-Terry regression trunk model, a novel probabilistic approach for the analysis of preference data expressed through paired comparison rankings. In some cases, it may be reasonable to assume that the preferences expressed by individuals depend on their characteristics. Within the framework of tree-based partitioning, we specify a tree-based model estimating the joint effects of subject-specific covariates over and above their main effects. We, therefore, combine a tree-based model and the log-linear Bradley-Terry model using the outcome of the comparisons as response variable. The proposed model provides a solution to discover interaction effects when no a-priori hypotheses are available. It produces a small tree, called trunk, that represents a fair compromise between a simple interpretation of the interaction effects and an easy to read partition of judges based on their characteristics and the preferences they have expressed. We present an application on a real dataset following two different approaches, and a simulation study to test the model's performance. Simulations showed that the quality of the model performance increases when the number of rankings and objects increases. In addition, the performance is considerably amplified when the judges' characteristics have a high impact on their choices. Show less
Pulmonary embolism is a serious and potentially life-threatening disease in the acute phase, and may also have a major impact on a patient’s daily life in the long run. The overall aim of this... Show morePulmonary embolism is a serious and potentially life-threatening disease in the acute phase, and may also have a major impact on a patient’s daily life in the long run. The overall aim of this thesis was evaluating important aspects of the post-pulmonary embolism syndrome with an emphasis on early diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH) and the associated consequence for patients’ prognosis. Show less
