PAD emotional state model
The PAD emotional state model is a psychological model developed by Albert Mehrabian (1997 and after) and James A. Russell to describe and measure emotional states. PAD uses three numerical dimensions to represent all emotions.
The PAD (Pleasure, Arousal, Dominance) model has been used to study nonverbal communication such as body language in psychology. It has also been applied to consumer marketing and the construction of animated characters that express emotions in virtual worlds.
The dimensional structure
PAD uses three-dimensional scales which in theory could have any numerical values, but in practice are limited to specific states. The dimensional structure is reminiscent of the 19th century work of Wilhelm Wundt who also used a three-dimensional system and also the 20th century work of Charles E. Osgood.
The Pleasure-Displeasure Scale measures how pleasant an emotion may be. For instance both anger and fear are unpleasant emotions, and score high on the displeasure scale. However joy is a pleasant emotion. This dimension is usually limited to 16 specific values.
The Arousal-Nonarousal Scale measures the intensity of the emotion. For instance while both anger and rage are unpleasant emotions, rage has a higher intensity or a higher arousal state. However boredom, which is also an unpleasant state, has a low arousal value. This scale is usually restricted to 9 specific values.
The Dominance-Submissiveness Scale represents the controlling and dominant nature of the emotion. For instance while both fear and anger are unpleasant emotions, anger is a dominant emotion, while fear is a submissive emotion. This scale is also usually restricted to 9 specific values.
A more abbreviated version of the model uses just 4 values for each dimension, providing only 64 values for possible emotions. For instance, anger is a quite unpleasant, quite aroused, and moderately dominant emotion, while boredom is slightly unpleasant, quite unaroused, and mostly non-dominant.
The abbreviated model has also been used in organizational studies where the emotions towards specific entities or products marketed by them are measured.
The PAD model has been used in studying consumer behavior in stores, to determine the effects of pleasure and arousal on issues such as extra time spent in the store and unplanned spending.
Virtual emotional characters
The PAD model, and the corresponding PAD Space have been used in the construction of animated agents that exhibit emotions.For instance, Becker et al. describe how primary and secondary emotions can be mapped via the PAD space to features in the faces of animated characters to reflect happiness, boredom, frustration or annoyance. Lance et al. discuss how the PAD model can be used to study gaze behavior in animated agents.
Zhang et al. describe how the PAD model can be used to assign specific emotions to the faces of avatars. In this approach the PAD model is used as a high level emotional space, and the lower level space is the MPEG-4 Facial Animation Parameters (FAP). A mid-level Partial Expression Parameters (PEP) space is then used to in a two level structure: the PAD-PEP mapping and the PEP-FAP translation model.
- Mehrabian, Albert (1980). Basic dimensions for a general psychological theory. pp. 39–53. ISBN 0-89946-004-6.
- Bales, Robert Freed (2001). Social interaction systems: theory and measurement. pp. 139–140. ISBN 0-7658-0872-2.
- Mehrabian, Albert (2007). Nonverbal communication. pp. 10–15. ISBN 0-202-30966-5.
- Ratneshwar, S.; Glen, David (2003). The why of consumption: contemporary perspectives on consumer motives. p. 39. ISBN 0-415-31617-0.
- Becker, Christian; Kopp, Stefan; et al. (2008). "Why Emotions should be Integrated into Conversational Agents". In Nishida, Toyoaki. Conversational informatics: an engineering approach. pp. 49–59, 61. ISBN 0-470-02699-5.
- Bales, Robert Freed (2001). Social interaction systems: theory and measurement. pp. 137–143. ISBN 0-7658-0872-2.
- Ashkanasy, Neal M.; Cooper, Cary L. (2008). Research companion to emotion in organizations. p. 200. ISBN 1-84542-637-1.
- Lance, Brent; et al. (2008). "Relation between Gaze Behavior and Attribution of Emotion". In Prendinger, Helmut. Intelligent virtual agents: 8th international conference. IVA. pp. 1–9. ISBN 3-540-85482-7.
- Zhang, S.; et al. (2007). "Facial Expression Synthesis using PAD Emotional Parameters for a Chinese Expressive Avatar". In Paiva, Ana; Prada, Rui; Picard, Rosalind W. Affective computing and intelligent interaction. pp. 24–33. ISBN 3-540-74888-1.
- Valdez, P.; Mehrabian, A. (1994). "Effects of color on emotions". Journal of Experimental Psychology 123 (4): 394–409.