Fitts' Law

Fitts Law

It is nice to know that there are actual scientific and quantifiable ways to approach study of interaction. Fitts law shows us that we can actually model people's interaction with systems in a quantifiable way, by relating the number of errors in using an interface element to its proximity and size.

I suspect that microsoft has begun to use Fitts' law in designing some of their newer software, such as the "ribbon" interface of MS Office. I say this because they make use of buttons in the interface whose size is dependent on how important they are. Also the buttons are arranged so that they are closer together, making errors less likely once the system is known.

The Inmates are Running the Asylum

The Inmates are Running the Asylum

Alan Cooper

This book is essentially an argument for the existence of interaction design consultants. It discusses the problems associated with giving the task of interface design to managers, marketers and programmers and argues for the use of interaction designers to completely design the system before any implementation is begun.

I agreed with much of what this book had to say about not only managing projects but also about the design process and attitudes of software engineers. I have seen much of what the author mentions in my own projects, where I get so caught up in what I have to do to program a project that I lose track of how people will ultimately use it. I think in terms of which features I want to have and not necessarily in what is needed to support a specific activity or fulfill a need. When engineering software I feel extremely liberated when I do not have to come up with the interaction design as well and can just focus on getting an already agreed upon design constructed correctly. However I do not feel their should be a complete disconnect between those who implement software and those who design the interactions, and neither does the author. Designers need to understand what is required to implement their designs, and most importantly need to understand what sort of interactions are feasible. That is not to say they should be conservative with their designs just because of their knowledge of the implementation, but they should be able to balance optimal interaction with reasonable implementation.

If and when I go into the software industry, I plan to make sure every software engineer I meet has read this, if only to make sure they acknowledge some of the problems associated with the software engineering mindset.

Providing Dynamically Changeable Physical Buttons on a Visual Display

Providing Dynamically Changeable Physical Buttons on a Visual Display

Chris Harrison Scott E. Hudson

This paper discusses work by the authors to create a simple and versatile system for dynamic buttons on visual displays. Their system involves the use of a malleable latex membrane that can be backlit to act as a screen, a vacuum to distort the latex and a backing that is used to create specific shapes with the distorted latex. The purpose of this interface is to add an element of physical feedback and interaction to touch screens.

While adding their system to generally static touchscreens can be useful in many specific applications (such as car interfaces, ATM pin pads etc.) the lack of dynamism limits its use in my opinion. They make the point that the backing is easy to produce and change, making it simple to create new physical interfaces for systems. However, this is not truly dynamic and almost defeats the purpose of using touch screens for interaction (that interaction can be defined programmatically to support a variety of activities). If you are presented with a "dynamic" pin pad interface, there is only so many different activities you can map onto a pad with 3 rows of 3 buttons, even if those buttons could be enabled or disabled separately.

In spite of these reservations, I feel this could be a significant boon to some of the applications suggested in this paper, specifically car dashboards and control panels. These interfaces do not need to be too dynamic and are significantly easier and safer to use when they can be operated by touch instead of sight. This system combines the advantages of physical interfaces with some of the dynamic ability of touch display systems.

Human Centered Design Considered Harmful

Human Centered Design Considered Harmful

Donald "Don" A. Norman

In this article, Don Norman discusses some of the problems of focusing on the "user" for design. In particular he feels that designing specifically for the user should perhaps be replaced with designing for an activity or task. In designing for the user we often overlook what it is the user is actually trying to achieve and what sort of inherent design issues are present in the activity, and instead focus on trying to make the interface human friendly. As he points out in the article, well used systems such as musical instruments and handwriting are well adapted to their specific activities but are on the whole not very "Human friendly".

I like the points Norman makes in this article. Personally I feel the best interface is the one that supports the quickest and most efficient way to perform an activity or task. Once the interface is constructed with this in mind we can then go back and use Human centered design techniques to refine the interface with human use in mind.

Usability Evaluation Considered Harmful

Usability Evaluation Considered Harmful (Some of the Time)

Saul Greenberg Bill Buxton

In this paper, Greenberg and Buxton discuss some problems that are associated with current methods of user interface evaluation, namely an overuse of quantitative usability studies in cases where other methods of evaluation might be more appropriate.

I find this particularly interesting as it brings up the question (to me) of whether CHI truly is a "hard science" where specific testing methods are generally sufficient and indeed necessary to evaluate a solution. Because of the great variety of goals in systems developed in CHI it is easy to see that one testing methodology is not going to be sufficient to test the usefulness of all systems.

A somewhat disturbing point that the authors bring up to support this claim, is the trend of researchers designing systems with the idea of qualitative evaluation in mind. If you are designing a system so that it specifically does well in the tests you plan to put it through, doesn't that really invalidate the tests you are going to perform? What does that prove about the system, that it performs exactly as hoped in the specific highly controlled environment you put it in. Even then, is it actually a system that should be evaluated in this way?

I agree with the authors that testing should be more flexible and actually fit the problem that is being addressed, and thus not necessarily quantifiable. Perhaps a new testing system should be created for each new system instead of recycling old test and trying to recast the problem into an existing mold.

Ethnography Considered Harmful

CHI 2009

Ethnography Considered Harmful

Andy Crabtree, Tom Rodden, Peter Tolmie Graham Button

This paper is essentially a caution written towards interactive designers about the dangers of the wholesale use of sociological ethnographic methods. The authors feel that even though computing is moving into a new level of ubiquitousness it does not mean that designers should throw away old task and work specific study methods. They feel that the new methods being employed are too centered on creating a story and not on focusing on applications and uses of technology.

I feel that these arguments are certainly fair, but that in finding new places to apply technology designers can't just look for existing tasks and work but have to create a broader picture of their target. Just as it makes no sense to only ask a user what they want and not considering what they might need, it makes little sense to study only what people are currently doing without asking what their goals and beliefs are and whether there is some system or solution that could fit those goals better than adapting what they already use.

Still, I can see that it is dangerous to only rely on a highly qualitative study of a group as this can lead to conclusions that are difficult to back up. Without well aimed quantitative study, working results that are gleaned from an ethnography could essentially be considered conjecture and do little to provide scientific proof.

CHI 2007: Software or Wetware

CHI 2007

Software or Wetware? Discovering When

and Why People Use Digital Prosthetic Memory

Vaiva Kalnikaitė , Steve Whittaker

This paper investigates the use of prosthetic memory (both electronic and traditional) vs the use of organic memory. They compared usage of their journaling system, ChittyChatty, an audio recorder, organic memory and pencil and paper notes. They evaluated the four over a period of 1 to 30 days, asking users about the perceived efficiency, usability and accuracy of the systems.

As a result, the studies found that people like the ease of use of organic memory and pencil and paper over the short term, but that these degraded quickly in their usability and accuracy over time. They also found that their system ChittyChatty was generally well liked.

While their studies are interesting, especially for design of memory aid devices, I found their ChittyChatty system most interesting. It is a free hand note taking software that also records audio simultaneously, associating text notes with the audio recorded at the time. I think that would be extremely useful in the context of classes because you could essentially manually index the audio so you know where certain events occurred. Then you can quickly go back and listen to the audio for more details instead of having to write all the details at once.

UIST 2007: Gaze-enhanced Scrolling Techniques

UIST 2007

Gaze-enhanced Scrolling Techniques

Manu Kumar, Terry Winograd

In this paper the authors present several possible ways of using eye gaze detection to make reading text easier, and also present a few other interactions made possible by gaze detection. For the text reading system they had two main types: manual scrolling with gaze enhancement and automatic scrolling of various types.

Manual scrolling with gaze enhancement lets the user use page up and page down to manually go to the next section of text. However as the user pages, the system detects which line they were reading before they paged and highlights it in its new position once the text has finished moving.

Automatic scrolling came in a few different forms. The first is "Eye in the Middle" where the system measures the user's reading speed and adjusts the text scroll to match it. Another technique was smooth autoscrolling which had specific zones of control. If the reader was reading towards the top of the page, scrolling would stop. As the reader moves down the page begins scrolling and if the reader is near the bottom the page scrolls even faster. Finally there is an automatic page up and page down, where if the reader looks at the bottom of the screen for a long enough period (150-200 ms) then the page would page down.

In addition to the text, the researchers also created buttons that would be activated by the user looking off the screen in certain directions.

In a very small user study, the researchers found that the gaze enhanced methods were preferred, specifically the ones associated with discrete page up and page down, as the users found it somewhat difficult to read moving text.

I found the whole gaze assisted scrolling techniques interesting, particularly the use of a short activation period when gazing to determine if that was indeed the user's intention to scroll. There could be some very interesting uses for this (for example switching between windows in a desktop environment or somesuch)