Overview

The notion of using ‘patterns’ to document good design practice was first proposed by Alexander in the domain of architecture and urban planning. The notion of design patterns has been enthusiastically embraced by the software design community. In a translation from the original domain, a number of general patterns have been documented for reuse across a range of software systems. In this work we proposed the analogous notion of patterns of cooperative interaction which are patterns of cooperation and computer use that recur across a range of settings, and can be derived through ethnographic field studies. Through re-examining the corpus of ethnographic studies and conducting new studies we identified a series of patterns of cooperative interaction; i.e. a series of different types of computer (and other artefact) use and cooperation, with at least two specific examples of each type from different settings.

Contrary to other forms of patterns, our patterns are descriptive of the activities in a given setting, rather than being solution oriented. They are meant to convey details of work, cooperation and interaction that are similar across different settings, to serve as an informational resource when considering dependable systems design in novel settings with similar attributes to those in our archived patterns collection. Our pattern collection is therefore meant to inform the process of social analysis of work. Pattern examples point to interesting features of social and cooperative system use that it is important to take into account when designing novel technologies to support that work.

By presenting abstracted, generic, patterns of cooperative interaction along with specific examples of those patterns from fieldwork we aim to make ethnographic material more amenable and more easily communicable to system designers. At the generic pattern level, designers can grasp a concept that applies to a number of situations of social and cooperative system use, while the provision of specific instances from fieldwork allows them to see the analytic purchase that can be gained by comparing and contrasting examples of the same pattern in the details of any given setting. In this way, our patterns move away from the dense, narrative descriptions of conventional ethnographies while directing the user of them to find the right balance between understanding general features of cooperative activity and their specific rendering in a given setting.

For our patterns collection we constructed a template 'language' to define these patterns, then presented our collection on the WWW. At the generic level (the front web page for each pattern), each pattern is given a name that captures its essence, then this essence is described, below this are three further sections relating to ‘design for dependability’. The first section details why the pattern is ‘useful’, the second ‘where used’ (i.e. in which settings we have found examples of the pattern), and the final section details some ‘design implications’. By clicking on hyperlinks to the individual settings listed in the ‘where used’ section, readers gain access to the pages listing the specific examples.

According to our template, five features of each specific example are detailed: (1) Cooperative Arrangement - a basic description of the people and technologies involved in the pattern example; (2) Representation of Activity – a description of any representations involved in the example; (3) Ecological Arrangement – a description or diagram of the layout of the example; (4) Coordination Techniques – the means by which the people coordinate their activity; (5) Community of Use – the user groups involved in the example.

Our pattern collection details 10 generic patterns with around 25 specific examples. Our patterns are also listed on wiki pages so others can add to our collection on-line, as well as another set of wiki pages that list a series of patterns derived from a single study of extreme programming (XP).

Explanation

The patterns collection forms a general resource for learning about different aspects of social and cooperative work that are important to consider when designing systems to support that work. Achieving dependable systems design and implementation is now considered to be a process where attention needs to be paid not only to the technical system but also to the social and work environment into which the system will be placed. Dependability is seen as a property of the whole socio-technical system. Particular consideration is required to understand how well the technical system will fit with the activities of the users in the proposed setting (the application domain). For instance, highly dependable technical systems may be part of an undependable socio-technical system because they are inappropriate to the setting and users. Ethnographic studies have been very useful in describing the details of social aspects of work but have tended to yield results that are seen as specific to the setting studied. Patterns of cooperative interaction provide a means of generalising and comparing and contrasting findings across settings to allow the re-use of ethnographic data.

Guidance

For designing in a given setting, the user can see whether any features of the work in that setting correspond with any of the patterns. This can be done in one of two ways. The patterns user can conduct a basic observational study then compare their results to the patterns collection. Or they can approach the setting with the patterns collection in mind and see whether any aspects of the setting and activities are similar to the patterns. By considering any relevant patterns and how they relate to the specifics of the setting the patterns user should be able to generate design issues and considerations as the patterns illustrate how certain arrangements of people and technologies facilitate or constrain certain types of work activities. In this way, the patterns provide a route to thinking through dependable design concerning social and cooperative aspects of work. Another aspect of the collection is that it is open for contributions, of new patterns or pattern examples, as the wiki pages may be added to on-line.

Examples of patterns are included with each pattern description.

Contributors: David Martin, Tom Rodden, Mark Rouncefield, Ian Sommerville, Steve Viller