Assignment 7: Usability

Readings

• Chapters 1 and 2 of Don Norman’s The Design of Everyday Things

• How to Conduct a Heuristic Evaluation (Links to an external site.) from Jakob Nielsen

• 10 Usability Heuristics for User Interface Design from Nielsen

Assignment

Choose an everyday task that involves using some technology, such as making coffee or buying a train ticket. Explain how the gulf of execution and the gulf of evaluation could lead to problems performing this task. Be specific. Then, explain whether any of Nielsen’s heuristics fail for this task.

Task: Turning off the Lights with Alexa

Heuristic Evaluation leading to Problems

The article states,

"If the system is intended as a walk-up-and-use interface for the general population or if the evaluators are domain experts, it will be possible to let the evaluators use the system without further assistance."

Since Alexa is a walk-up-and-use interface, users can test the light system without knowing much about the interface. Although the users have not named the lamps themselves, which will cause problems. Alexa will struggle to match the name the user said to a name of a lamp that exists. If the users were provided a usage scenario, (for example: a list of the lamp names in the home) the evaulation would be doable.

Because these tests last 1-2 hours, it is hard to understand the real problems the interfaces encounters. A large problem I have encountered is lack of memory for lamp names. Since the users will recieve a sheet of paper with all the lamp names, it is not realisitc in an every day use case. Users do not interact with alexa and the lights straight for 1-2 hours at a time. Instead, it is quick 10 second interactions multiple times a day.

Current Task Failures

1. Visibility of System Status

   Alexa plays a sound after action is completed. The sound will go off regardless if the action was successful. For example, if I physically turned off the lamp I connected to Alexa, and asked her to “Turn on the lamp”, it wouldn’t turn the light on but would still make the sound.

2. User Control and Freedom

   If I accidently tell Alexa the wrong light name, I can’t stop mid sentence. I have to wait for Alexa to repeat the name back to me, and confirm it was the right or wrong one. For example, If I say “Alexa turn off bedroom lamp CANCEL” she will respond with “I can’t find the lamp Cancel”

3. Consistency and Standards

   I am unable to use multiple names for a light. If I use the word light to turn off something named lamp, Alexa will get confused. For example, if I say “Alexa turn off bedroom light”(when I meant bedroom lamp), she will say “Sorry, I can’t find bedroom light”.

4. Recognition rather than Recall

   My boyfriend can never remember what I named the lamps in the house. When we go to bed, he says “Alexa turn off all the lights” to avoid memorizing the lamp names. It is hard to remember every individual name of a lamp when there are so many in the house and you don’t use them regularly.

5. Flexibility and Efficiency to Use

   Every night at a certain time I tell Alexa to turn off the bedroom lamp. Alexa should recognize which lamp I want to turn off based on patterns of usage to make my life involve less thinking.