The Performance of Touch Screen Soft Buttons

This paper was published by Seungyon Lee and Shumin Zhai.

In this paper, Lee and Zhai investigate how efficient soft buttons are, compared to traditional hard buttons. After an introduction, they discuss four basic properties of touch screen interaction:

• Operational mode (stylus or finger)
• Activation mechanism (contact with screen or force applied to screen)
• Feedback enhancements (audio or vibro-tactile)
• Button size

The rest of the paper is dedicated to three experiments designed to test the effects of these properties on speed and accuracy. The first experiment tested operational mode and feedback on soft and hard button devices. They found that there was little difference between audio and vibration feedback on a soft button device. Also, hard and soft buttons performed at nearly the same level of accuracy and speed, with finger-operated soft buttons being slightly worse.

The second experiment compared contact-based (capacitive) screens with force-based (resistive) screens. As with the first experiment, accuracy was very high for all types of activation, including hard buttons. While capacitive and resistive screens each have pros and cons, Lee and Zhai point out that they are essentially equivalent and actually perform slightly better than hard buttons.

The third and final experiment was the only one where variables actually made a significant difference in the results. In it, they tested button size versus activation mode. While speed did not change significantly in small versus large buttons, the number of additional characters entered to correct errors was much higher with small buttons.

I found the results of this paper to be a little surprising, as I assumed that hard buttons would always out-perform soft buttons. That being said, I feel like they could have eliminated some repetition in describing their findings. Reading the description and then the summary of each experiment would have been enough to get all necessary information, without the lengthy middle section. This is especially true on the first two experiments where the results for the different variations were statistically the same. Still, the paper was informative and provides a good basis for future work in the area of soft button design.

The Design of Everyday Things

In his book, Donald Norman gives his thoughts on good and bad design, using common objects as his examples. The first chapter gives some important considerations when designing objects:

• Affordances - Does the design indicate the proper use?
  
• Conceptual models - Does the design make it easy to determine how the device works?
  
• Visibility - Does the design make its functions apparent?
• Mapping - Does the design of the device's controls have a strong correlation with the action they perform?
• Feedback - Does the device indicate to the user the result of his/her action?

He covers multiple things that hinder and aid good design, as well as how a designer should approach a new (or old) design problem. He applauds doors designed to indicate where to push and derides light switches and stove controls laid out in 1D to control items in 2D. He also points out how people are quick to decide why their computer crashed or why the projector doesn't work, and how this is usually a result of a problem with the above list of design principles.

Towards the end of the book, he begins to extend his points to the design of computers and applications. Many of his earlier points relate as much to the design of doors as they do to the design of computers. He concludes with a message to the designers (and users) of the future, to not ignore design as devices become more powerful and feature-filled.

I felt like Norman's book was an interesting and easy read. (Perhaps it was well designed!) Norman was able to get his point across in a very understandable way by using our own experiences with confusing appliances and easy-to-use (though complex) cars. I learned a lot from his book, or rather, it brought what I already knew into my conscious thought process. I believe that his book will be a good reference for user interface design in the future, as it provides a reminder that design is not just a shiny GUI you slap onto an application; instead, it is a crucial part of the development process that should not be forgotten.

The Application of Forgiveness in Social System Design

This paper was submitted by three researchers: Vasalou (University of Bath), Riegelsberger (Google UK) and Joinson (University of Bath).

This paper focuses on extending the concept of forgiveness to online communities. It begins with an overview of common online interaction problems, and practical ways that the offenders are punished. Examples include reputation on Slashdot and eBay, as well as moderation and page-locking on Wikipedia. Problems arise when a user inadvertently offends someone or has a momentary lapse of judgment. In these cases, users often desire a reparation system, which could allow their status in the community to be restored. The three researchers listed above, believe that this would best be implemented through a system of forgiveness.

In their paper, they borrow the following definition: "Forgiveness is the victim's prosocial change towards the offender as s/he replaces these initial negative motivations with positive motivations." They extend this to state that:

• Forgiveness cannot be mandatory
• Forgiveness is not unconditional
• Forgiveness does not necessarily repair trust or remove accountability

With these principles, they hope to encourage communication between the victim and the offender, allowing misunderstandings to be cleared up, and legitimate offenses to be talked through. They point out that simply blocking the offending user (even temporarily) simply encourages them to leave, since they are alienated from the community. The opportunity for forgiveness, however, helps to build stronger communities, much like it helps build strong friendships in everyday life.

This paper felt a little vague and unscientific, even though they constantly referenced other sources. While I agreed with almost everything they said, I found it to be less than enlightening. Rather, it seemed to reiterate what most people could put together off of the top of their heads (albeit without sources). It would have been nice for them to conduct a user-study of an actual online community, using an actual forgiveness system. I believe this is a great idea for many online communities, but it would need to be tested in the real world, not just talked about on paper.