in Process

How Designers Follow Constraints

Notes on Web Site Designs: Influences of Designers Experience and Design Constraints (PDF) by Aline Chevalier and Melody Y. Ivory, which ‘demonstrates that the designers’ levels of expertise (novice and professional) as well as the design constraints that clients prescribe influences both the number and the nature of constraints designers articulate and respect in their web site designs.’ It’s part of the WebTango project at the iSchool, University of Washington.

‘We assert that understanding designers’ activities and identifying difficulties they encounter are essential to improving web site quality.’

‘we found studies showing that constraints are extremely important for understanding and for solving a design problem’

‘there is a wide gap between designers’ articulation of constraints and designers’ effective implementation of them.’

Those pesky designers! Seriously, reading this I feel like we could do a better job making constraints explicit in our personas and scenarios. Most I see are filled with a lot of nice details on our fictional character meant to make them more real but doesn’t add anything to the design process.

Also, I feel like we need something in-between the personas/scenarios and the design, an interaction model. More on this in a future post.

Even the experienced designers could only satisfy 75% of the constraints they were given. While they achieved up to 95% of the client constraints, they couldn’t satisfy more than half of the user constraints.

‘professional designers in the condition without constraints were able to infer client constraints, because they had contextual knowledge acquired through experience (stored as mental schemata)’

‘Results from the first two studies show that professional and novice designers encounter difficulties in effectively considering users’ needs during the design process, even though they focus mainly on users’ needs during the evaluation process.’

‘we argue that heuristic evaluation with ergonomic criteria suggested by Nielsen (2000) has not been adapted for web site designers (who have no human factors knowledge), because the ergonomic criteria are both too abstract and too numerous. Our hypothesis is that it would be more effective to provide designers with a subset of ergonomic constraints that respect the users’ real needs.’

Absolutely. There are simply too many guidelines to follow these days. There has to be a way of winnowing them down. Design patterns might help. A better design method might help.

Results: ‘1. Help novice designers to consider both user and client constraints. 2. Help professional designers to focus more so on user than client constraints or at least help them to strike a balance between the two actors. 3. Help designers, regardless of their levels of expertise, to consider and implement ergonomic constraints in their sketches.’

For the first two points, we suggest developing a knowledge-based system that fits the designer’s level of expertise (see Fischer et al., 1991). Specifically, the system should provide the following support:

  • The system should help novice designers to identify constraints that need to be respected in the web site design.
  • This system should also help novice designers to generate new constraints, through a design step oriented on the expectations of the client and the users. The system could help designers determine, based upon the current state of the design activity, additional information the designer may need to consider. For example, the system could propose questions for novice designers to ask the client.
  • The system should help professional designers deal with a client who has many expectations, in particular, to help the designer consider more user constraints. For example, the system could suggest relevant constraints that the designer did not consider.

As solutions they suggest a focused questionnaire designers could use to evaluate designs through the design process, or an automated tool to evaluate the design. Both are probably helpful, but to truly advance I think we need to improve the method itself, not just devise better ways to find design flaws.

Thank you Aline and Melody.