Product Semantic Analysis (PSA)
A semantic scale that is built for each evaluation case separately via user interviews and by using product semantics as the theoretical basis.
Identifying and evaluating the semantic qualities of products have most often been dealt with in an intuitive manner. In order to design products with specific, desired semantic qualities, product developers' methods and tools need to support the identification of consumers' requirements as well as the evaluation of a product's. The theoretical basis is product semantics. Product semantics have been defined as ".... the study of the symbolic qualities of man-made forms in the cognitive and social context of their use and application of knowledge gained to objects of industrial design." (Krippendorff & Butter 1984). According to this definition, product semantics concerns the relationship between, on the one hand, the user and the product and, on the other, the importance that artefacts assume in an operational and social context. Monö (1997) has chosen to describe the product as a kind of trinity. The first dimension, the ergonomic whole includes everything that concerns the adjustment of the design to human physique and behaviour when using the product; the technical whole stands for the technical function of the product, its construction and production; and, finally the third aspect, the communicative whole, designates the product's ability to communicate with users and its adjustment to human perception and intellect (Monö 1997). Through the product gestalt (i.e. the totality of colour, material, surface structure, taste, sound, etc. appearing and functioning as a whole), the product communicates a message, which is received and interpreted by the customer/user. This message is, according to Monö (1997), 'created' by four semantic functions:
• to express: The product gestalt expresses the product's properties, for instance stability, lightness or softness.
• to describe: The product gestalt can describe the product's purpose and its function. It can also describe the way the product should be used and handled.
For instance, a doorknob can describe the way it should be gripped and turned.
• to exhort: The product gestalt triggers a user to react in a specific way without contemplating or interpreting the product's message. For instance the user is triggered to be careful and to be precise in his/her operation of the product.
• to identify: The product gestalt identifies, e.g., origin and product area. A bowl can be identified as part of a specific china set; a company can be identified by
its trademark or by a specific design philosophy apparent in its products.
The PSA method addresses the function “to express”.
The method involves several steps:
-interviews with consumers and producers/designers to identify relevant words (adjectives) for the product domain (Note: specific for each product/product area);
-reduction of adjectives and construction of semantic scale and instrument including preferred and non-preferred expressions. A visual, analogue scale is recommended for increased sensitivity. The scale is anchored in two points with a neutral middle (maximum value – neutral – maximum value). Instead of using adjectives with opposite meanings, however, only one adjective is used, e.g. “masculine”, while the other end is anchored in “the opposite”.
-interviews with consumers and/or producers/designers to identify a desired product semantic profile. This will show the desired strengths of different expressions;
-and consumers ratings of the perceived expression of a product design using the instrument.
The PSA method provides a structured process in which the desired qualities can be identified and described in terms of a desired product semantic profile, and the design solution evaluated and compared against the desired profile. The PSA method contains several steps; interviews with customers, construction of semantic scale, consumer/user ratings by means of scale etc. The distinctive feature is the way these steps are combined. The PSA method has a thorough theoretical basis. The PSA does not rely so heavily on statistics as do, e.g., the Kansei methodology.
The method has so far only been used to address visual aspects (April 2006). Research activities have begun to evaluate approach product expressions from a haptic perspective.
Karlsson M A & Wikström L (1999): Beyond Aesthetics! Competitor Advantage by an Holistic Approach to Product Design. In Proceedings from the 6th International Product Development Management Conference, Cambridge July 5-6, 1999, p. 629 -638
References describing the method
Wikström, L (2002): Produktens budskap. Metoder för värdering av produkters semantiska funktioner ur ett användarperspektiv. (Product messages. Methods for the evaluation of semantic functions of products from a user perspective), Department of Product and Production Development, Chalmers University of Technology, Göteborg. In Swedish.