Navigate using audio

Announcements

  • Class next Tuesday is for meeting with your group
    • Project part C due that day

Timely user interfaces

Difference Between Quick and Long Response

  • Long delays
    • Negative
      • users forget
    • Positive
      • make less mistakes to avoid wait times
  • Short delays
    • Negative
      • More error prone
        • Users might become rushed
        • Perceived less error because of quick response time
    • Positive
      • users can learn
      • keep users’ attention

SRT

  • Audio 0:07:49.928513
  • system response time - number of seconds between a user’s activity to the display of the results
  • model
  • Audio 0:13:48.149731
  • You want to maximize the SRT time
    • This means moving the computer begins output line as far left as possible
    • Means displaying spinning wheel or whatever to let the user know information is being processed

Rapid Task Performance, Low Error Rate, High Satisfaction

  • Audio 0:16:27.172385
  • What is needed for this
    • user knowledge
    • ease of navigation
    • solutions can be carried out without delays
    • distractions eliminated
    • anxiety low
      • Audio 0:19:12.712080
      • Avoiding or handling errors
      • user knowledge
    • accurate feedback
    • avoid or handle errors
  • Audio 0:22:21.264087
  • There are actually times you might want to slow down your interface
    • For novices especially

User Productivity and Variability

  • Audio 0:24:39.577520
  • Repetitive tasks
    • Menial tasks
      • If the system response time is different every time, it will confuse users
      • Short response will make them respond more quickly which could be good or bad
  • Users adapt to the response time
    • If the response time changes, users will change their work style
  • People like predictability

Frustration Reduction

  • Audio 0:27:42.154803
  • SRT should match expectations
    • If I move the mouse, it should move
    • If I’m doing something more complicated, it’s okay if it takes a long time
  • Reduce interruptions
  • Make sure the interface doesn’t fail
  • Show progress
    • Make sure it’s accurate
  • Improve training
  • Increase capacity
    • Upload speed
    • Response time

Guidelines

  • Audio 0:35:33.221472
  • People prefer shorter response times
  • SRT < 15 seconds
  • Shorter response time = shorter think time
    • error rates
  • SRT should be appropriate for the task
    • Typing, mouse, etc should be < 15 ms
    • Complex tasks
      • 2 - 4 seconds
    • Very complex
      • < 15 seconds
  • Rapid startups
    • If it takes too long to load, people might go somewhere else

User Experience With Data Latency

  • Audio 0:40:16.662149

Vocab

Term Definition
short delay positives users learn better and their attention is kept better
long delays negative users forget what they’re doing
long delays positive users make less mistakes
short delays negative users are more error prone
system response time (SRT) number of seconds between a user’s activity to the display of the results
characteristics needed for rapid task performance, low error rate, and high satisfaction user knowledge of the task, ease of navigation, solutions have low delay, user has low anxiety, give accurate feedback, avoid or handle errors
what can we do to reduce frustration? Match SRT with expectations, reduce interruptions, prevent errors, keep SRT < 5 seconds, show progress, feedback, improve training, increase capacity
response time guidelines people prefer shorter response times, SRT < 15 sec, SRT should be appropriate for task, rapid load