User Centred Design and Person Centred Design

By Gordon Rugg

There are often problems when a concept has a name which looks self-evident, but which is actually being used with a specific technical meaning.

This is the case with the terms User Centred Design (UCD) and Person Centred Design (PCD).

So what are these approaches, and why are they so different from other approaches to design, and why do these names lead to confusion?

In brief, User Centred Design and Person Centred Design with uppercase are names for methodologies containing specific methods and concepts. They’re terms of art, used with specific non-obvious meanings, hence the common confusions relating to them. So, what are the reasons for these approaches having arisen, and what is in them?

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Why do people behave like idiots?

By Gordon Rugg

Other people frequently appear to behave like idiots. As is often the case, there’s a simple explanation for this, and as is also often the case, the full story is a bit more complex, but still manageably simple once you get your head round it.

First, the simple explanation. People usually behave in a way that looks idiotic for one or more of the three following reasons:

  • Sin
  • Error
  • Slips

This model comes from the literatures on human error and on safety-critical systems; there are variations on the wording and on some of the detail (particularly around slips) but the core concepts are usually the same.

  • Sin (or “violations” in the more common version of the name) involves someone deliberately setting out to do the wrong thing. I’ll return later to possible reasons for people doing this.
  • Error involves people having mistaken beliefs; for example, they believe that closing a particular valve will solve a particular problem.
  • Slips involve someone intending to do one thing, but unintentionally doing something different; for example, intending to press the button on the left, but accidentally pressing the button on the right.

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Desire, novelty, and the attractions of safe Necker shifts

By Gordon Rugg

So what do wireframe Necker cubes have to do with enigmatic facial beauty, Rothko paintings, Sudoku, and video games? The answer is: Quite a lot.

In this article I’ll look at the deep structure of some popular passtimes, and consider some of the implications. This is the first in a short series of articles about the deep structures of desire.

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Crisp and fuzzy categorisation

By Gordon Rugg

Categorisation occurs pretty much everywhere in human life. Most of the time, most of the categorisation appears so obvious that we don’t pay particular attention to it. Every once in a while, though, a case crops up which suddenly calls our assumptions about categorisation into question, and raises uncomfortable questions about whether there’s something fundamentally wrong in how we think about the world.

In this article, I’ll look at one important aspect of categorisation, namely the difference between crisp sets and fuzzy sets. It looks, and is, simple, but it has powerful and far-reaching implications for making sense of the world.

I’ll start with the example of whether or not you own a motorbike. At first glance, this looks like a straightforward question which divides people neatly into two groups, namely those who own motorbikes, and those who don’t. We can represent this visually as two boxes, with a crisp dividing line between them, like this.

However, when you’re dealing with real life, you encounter a surprising number of cases where the answer is unclear. Suppose, for instance, that someone has jointly bought a motorbike with their friend. Does that person count as being the owner of a motorbike, when they’re actually the joint owner? Or what about someone who has bought a motorbike on hire purchase, and has not yet finished the payments?

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Iterative non-functional prototyping

By Gordon Rugg

Sometimes, product development is straightforward. The client tells you what they want; you produce it; they’re happy with it, they pay you, and everything is fine. This is known in the field as the waterfall model of development; once the client has signed off on the requirements, the process then moves irrevocably onwards, like a river going over a cliff.

When you and the client are dealing with familiar territory, this approach usually works reasonably well. Sometimes, though, things don’t work that way. You’re particularly likely to hit problems when you’re developing something that’s new territory for you and/or the client.

One common problem involves the client changing their mind part-way through development.

Another involves the client being unhappy with what you produced.

Communication problems are another frequent source of trouble, with you trying to make sense of just what the client wants, and getting more and more frustrated.

If you’re in that situation, or you think there’s a risk of getting into it, you might want to try iterative non-functional prototyping. It’s a lot simpler than it sounds, and it’s a fast, cheap, efficient way of getting to the heart of what the client wants, particularly when clients don’t actually know just what they want at the start. It involves looping through mockups systematically until the requirements are clear.

This article gives a short introduction to the core concepts and the process. It should be enough to let you get started; there’s supporting material elsewhere on this blog which goes into more detail about the underpinnings, which I’ve linked to within the article.

Waterfalls and loopsbannerv1Images from Wikimedia Commons: Attributions are given at the end of this article

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Intrinsic, extrinsic, and the magic of association

By Gordon Rugg

As regular readers of this blog will know, I have an awed respect for the ability of Ancient Greek philosophers to spot a really important point, and to then produce an extremely plausible but only partially correct explanation, sending everyone else off in the wrong direction for the next couple of thousand years.

Today’s article is about one of those points, where the Ancient Greeks didn’t actually get anything wrong, but where they laid out a concept that’s only part of the story. It involves a concept that can be very useful for making sense of consumer preferences and life choices, namely the difference between intrinsic properties in the broad sense, and extrinsic properties in the broad sense.

Here’s an example. The image below shows a pair of Zippo lighters. One of them is worth a few dollars; the other is worth tens of thousands of dollars, even though it’s physically indistinguishable from the first one. Why the difference? The answer is below…

zippo banner

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New Hyde and Rugg website

By Gordon Rugg

The new version of the Hyde & Rugg website is now live, here:

Among other things, it contains a resource section which pulls together our articles on a range of topics, including academic craft skills for students, elicitation methods, requirements, design, and education theory.

There’s also a section about our research, plus a section on the codes we’ve worked on. Again, these pull together our previous blog articles into a structured framework.

Over the next few months, we’ll be adding more material, particularly in the sections on academic craft skills and on our research.

We hope that you’ll find the site a useful complement to this blog.