The effects of prior experience on the use of consumer products

Abstract

Many products today are laden with a host of features which, for the majority of users, remain unused and often obscure the use of the simple features of use for which the product was devised (Norman in The design of everyday things. Basic Books, 2002; Keates and Clarkson in Countering design exclusion-an introduction to inclusive design. Springer, 2004). Since the cognitive capabilities of the marketed target group are largely not affected by age-related impairment, the intellectual demands of such products are frequently high (Rabbitt in Quart J Exp Psychol 46A(3): 1993). In addition, the age and technology generation of a product user will colour their expectations of the product interface and affect the range of skills they have available (Docampo in Technology generations handling complex User Interfaces. Ph. D. thesis, 2001). This paper addresses the issue of what features of products make them easy or difficult to learn to use, for the wider population as well as the older user, and whether and in what way individual prior experience affect the learning and use of a product design. To achieve the above, the interactions of users of varying ages and capabilities with two different everyday products were recorded in detail as they performed set tasks. Retrospective verbal protocols were then analysed using a category scheme based on an analysis of types of learning and cognition errors. This data was then compared with users' performance on individual detailed experience questionnaires and a number of tests of general and specific cognitive capabilities. The principal finding was that similarity of prior experience to the usage situation was the main determinant of performance, although there was also some evidence for a gradual, age-related capability decline. Users of all ages adopted a means-end or trial and error interaction when faced with unfamiliar elements of the interaction. There was a strong technology generation effect such that older users were reluctant or unable to complete the required tasks for a digital camera.Keywords Inclusive design Á Product design Á Cognition Á Training Á Working memory Experience and inclusive product designIn the context of demographic changes leading to an increasing number of older people, inclusive design research strives to relate the capabilities of the population to the design of products by effectively characterising the user. By 2020, almost half the adult population in the UK will be over 50, with the over 80s being the most rapidly growing sector. Recent research into inclusive design has investigated the relationship between the capabilities of the population at large; derived from statistical data sets, and properties and features of the design of products [1][2][3]. Products meeting the ideals of inclusive design aim to minimise the number of person who have difficulty with, or are excluded from use, or to control such exclusion by manipulation of product features [4,5]. A primary area of concern is with the cognitive capabilities of older users. In pa...

What is Good Design in the Eyes of Older Users?

“…This poses a challenge for designers: what can they do to ease the transition for these older users from their very familiar products to the unfamiliar, newer product interfaces? Previous experience with similar products is a strong predictor of usability, and those products that help the user make a reference to the same function on another more familiar device should perform better than those that do not (Lewis et al, 2006;Langdon et al, 2007). Furthermore, what innovators see as providing personal benefit may not be seen as such by the older person.…”

Characterising user capabilities to support inclusive design evaluation

“…There may also be an episodic buffer in working memory, which binds information represented in the other modality components, along with long term stored material, into unitary episodic memories that can be stored. Storage of material in the long term memory is also associated with the transformation from slow, error-prone novice to fast error-free expert performance as a result of repeated episodes of remembering [62].…”

“…Measures of recognition capability are required when comparing visible product features to information stored in Long Term Memory. Recall capability measures are needed for determining users' ability to retrieve stored knowledge about product features and behaviour [62]. Prospective memory is a special type of Long Term Memory for things that will occur in the future.…”

“…Therefore, in this paper, the concept of a mental model is used as a device that could enable the operational estimation of cognitive demands. Evidence shows that mental models are loaded into working memory using information stored in long-term memory cued by current environmental characteristics [6,55,62].…”

“…Mental models give rise to expectations of product functioning, and potential mismatches between a user's mental model and the actual way in which a device functions may lead to problems of usability. Because of this dependence on previous experience and continuous modification through successive interactions, mental models can be difficult to capture [55,62].…”