Processes of Design First lecture Interactive System Design

Processes of Design First lecture: Interactive System Design 3 October 2003 William Newman

Processes of Design: Overview Goal: gain an understanding all of the key steps in the process of designing an interactive system. Method: • Explore principles • Study and discuss designs • Learn and apply methods.

My background • Ph. D (Imperial College) in Computer Science, 1968 • Six years at Xerox Palo Alto Research Center, 1973 -79 • 15 years at Xerox Research Centre Europe (Cambridge) 1987 -2002 • Mostly focused on designing experimental interactive software systems • and on design methodology research • Now working as an independent consultant • Plus occasional teaching

Today’s Lectures • • Design What is it Examples to discuss Are there underlying principles? • Defining the design problem • Looking ahead…

What are Interactive Systems? And what does it mean to design them?

What is design? • Herb Simon: Everyone designs who devises courses of action aimed at changing existing situations into preferred ones. • Designing material artefacts is like • Prescribing remedies to a sick patient • Devising a new sales plan for a company • Finding one’s way around a traffic jam…

What have we designed recently?

Even the Greats get it wrong! • Rashtrapati Bhavan -- Edwin Lutyens’ Viceroy’s Palace

Alto: forerunner of today’s PC (1974) • • • 1 Mhz processor 64 Kbytes RAM 2 Mbyte disk yet… • • 5 Mbit Ethernet 808 -line display 60 ppm laser printer WYSIWYG text editor, graphics editors, windowed desktop… • See www. digibarn. com

The Bravo Word Processor • • Alto-based Multi-font, almost WYSIWYG Piece Tables No menus or targets! • Type i to insert, d to delete, e to select all, etc. • The ‘edit’ problem • Exposed the Modes problem • Direct forerunner of Word

The “Big Bushy Tree” of PC software ancestry Paths of design knowledge transfer See http: //www. digibarn. com/stories/desktop-history/index. html

Forget-Me-Not (Xerox Research Cambridge, 1993)

What’s involved in design? • Recalling Herb Simon: Everyone designs who devises courses of action aimed at changing existing situations into preferred ones. • Involving… • • Satisficing Finding alternative solutions Hierarchic subdivision Simulation

Modelling what designers do test retain • Creative thought involves trial-and-error heuristic and selection • See D. T. Campbell on Blind Variation and Selective Retention (1960) test reject heuristic known solutions

What this means for designers of interactive systems As designers, we need to know: • How to define and subdivide problems • Existing solutions and how [well] they work • Heuristics for varying existing solutions to solve new problems • How to evaluate solutions empirically • How to predict outcomes analytically As researchers, we need to make advances in all of these.