Phenomenology within psychology (phenomenological psychology) is the psychological study of subjective experience. In his phenomenological research, he outlined an epistemological frame using critical realism. IPA is one of several approaches to qualitative, phenomenological psychology. This experience of empathy is important in the phenomenological account of intersubjectivity. Establishing that phenomenological properties are amenable to individuation by causal role therefore requires argument. Rogers' theory of the self is considered to be humanistic, existential, and phenomenological. He was best known for combining phenomenological description with hermeneutics. The theory defines emotion(s) as an intricate process within neuromuscular, phenomenological, and neurophysiological areas. That theory in turn was grounded in phenomenological thinking. He described a hierarchical system of values that further developed phenomenological philosophy. It has since been described through phenomenological and microscopic theories. Mental properties are of two kinds, psychological and phenomenological. Regression analysis is sometimes used to create statistical models that serve as phenomenological models. Experimental psychologists have devised a variety of ways to indirectly measure these elusive phenomenological entities. These include studies on gamer cardiology, phenomenological correspondence and control abstraction and computer game pedagogy.