Ask Eric: Questions & Answers

October 7, 2005 – submitted by Marsha Harner of Irving, TX

Question: I have worked in several small start-up companies where the trend is to keep all ambient lighting to a minimum.(In other words, it's really dark in here.) They tell me it is to keep screen glare to a minimum. What are the recommendations for ambient and task lighting in an office setting when working on a computer?

In the dark,
Marsha Harner, CUA

Eric's response: This does sound uncomfortable, if energy efficient!

Here is the trick. Reduce the brightness on your computer screen. If your eyes have adapted to the low light levels the computer screen is likely to be uncomfortably bright. This will probably solve the problem.

The secondary concern will be if you can read paper or see the keys comfortably.

(Interestingly, I am sitting in the dark right now on a flight from Africa to India. I dropped the brightness and it is much better. Thanks for reminding me).

July 15, 2005 – submitted by Prashant Dubey of Ahmedabad, India

Question: I have to design an alarm system for an ATM. The requirements are huge in numbers, but one of them is about the security and in emergency, the alarm should activate.

Now, this one is something that doesn't come daily. Quite challenging. Can you please give your opinion about the principles of design about alarm systems, or what all should I keep in my mind while going for it?

One solution which I came across, is that with surveillance a camera, and a dedicated monitoring staff, this could be done. So, if they sniff something wrong or suspicious, they will raise the alarm, instead of the user doing that. Well, what about your thoughts!!

Thank you.

Eric's response: First you have to detect that an alarm condition is happening. This is a tough signal detection problem. The idea of having people watch videos might seem good. But the problem is they quickly zone out. You need something to draw their attention. Some of this can be done with automation. For example you can have a highlighted video display if there is sudden movement on screen or loud sounds. You MIGHT be able to do some pattern recognition (like for a gun in a hand. You also MIGHT be able to detect some interface characteristics that are associated with problems. For example money not taken out of machine fast enough. Certainly you can build in tilt switches. In each case you can have a security person immediately view the scene.

A panic button seems like a potentially useful idea. Users might have time to press it.

Once an alarm condition is detected you must sort out how to handle it. Clearly the alarm has to be loud enough to get attention. A silent alarm seems inappropriate as you probably want to deter the activity immediately instead of hoping a squad car can reach the site in time.

Consider the value of a real human voice. A recorded voice is unlikely to have the effect of a real person. The voice would then identify the situation to indicate that the situation has been understood and warn that pictures have been taken and the police are alerted.

July 7, 2005 – submitted by Anonymous

Question: Can I know the impact of the usability of the Global Positioning Navigation System for motorcycle use?

Eric's response: The GPS navigation will provide onboard guidance for where to go. I'm not really sure about the consequences off hand. Certainly there are dangers in trying to use the unit while driving. The seriousness of this will be very much dependent on the unit's design. There are also advantages where the user is less likely to get lost, and possibly have an accident trying to read a map while driving, or looking for signs instead of oil slicks.

I think one could not ask for a more interesting and critical usability engineering project. Prepare for trips to court to testify at liability suits.

March 10, 2005 – submitted by Sheree Reeves of USA

Question: Do you have any statistics on the percentage of user who use chat vs. phone for help on financial Web sites?

Eric's response: Any specific client figures would have to be kept confidential of course. However there is obviously a major preference for phone over chat.

Phone is easier and more personal. Which means there is one condition where the IMPERSONAL nature of voice response, chat, or email is an advantage. I have seen that users prefer these impersonal channels when the content is likely to be embarrassing. An example is getting balance information when the account is likely to be small or overdue.

February 22, 2005 – submitted by Tony Gullaci of Canada

Question: We are in the process of introducing Tablets to our Field Investigation Officers. I'm assuming that the principles of usability and good user interface design are still valid with this type of technology. Am I correct to assume this or do Tablets require special usability considerations when designing the user interface?

Eric's response: Usability methodology and principles CERTAINLY apply to tablets. But, there are also special issues. Consider first the question of the value of tablets. These are cool new technology and so are often applied where there is no real value. The form factor may make it easier to operate the tablet during an interview. However I am concerned about text entry. If the investigator is checking a box, that will be fine. But entering a name (where errors are critical) may be quite a problem. Handwriting recognition will tend to be slow and error prone (even though people subjectively like it about as much as a keypad). The keypad is a better bet; but selecting from a keypad with a stylus is still slow.

If designing for a tablet the basic rules of navigation, layout, wording, color, and graphics apply. Probably the biggest issue is the interactivity with the stylus and the impact of choice and design of controls.