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Illusion of Time. When 60 sec is not 1 minute

Illusion of Time. When 60 sec is not 1 minute

The magician takes the ordinary something and makes it do something extraordinary. Now you’re looking for the secret… but you won’t find it, because of course you’re not really looking. You don’t really want to know. You want to be fooled”. These lines from the cult film “Prestige” are about a magic trick. Modern frontend developers have to be a little bit of magicians too – show something that people want to see while doing real work behind the scene. Developers these days have to manage user’s perception and influence user’s expectations.

Denys Mishunov

April 20, 2015

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  1. WEB TIME LINE 0.2s 1s 5s 10s User Flow (2-5s)

    Attention Span (7-10s) Instant (0,1-0,2s) Immediate (0,5-1s)
  2. PLATFORM SUCCESS MODEL http://goo.gl/GlxjdN 1. loading 2. finger down 4.

    finger up 1000ms max: 100ms idle/cleanup in 50ms chunks Instant (0,1-0,2s) Immediate (0,5-1s)
  3. 20% RULE jnd = 20% of D jnd D <

    30s Photo: http://goo.gl/jQnZlP
  4. jnd = 20% of D 20% RULE 20% RULE 10s

    8s 12s -20% +20% Photo: http://goo.gl/jQnZlP
  5. –Lewis Carroll, “Alice in Wonderland” “My dear, here we must

    run as fast as we can, just to stay in place. And if you wish to go anywhere you must run twice as fast as that.” Operational Management
  6. FRONT END Delay blocking request (onLoad) WebWorkers AJAXify navigation …

    you-name-it HTML Javascript Images CSS Minification & Concatination Sprites Responsive sizes Lo-Fi background JPG images … Fewer HTTP requests CDN DNS prefetching … No CDN Inline top-screen CSS … Operational Management
  7. –Lewis Carroll, “Alice in Wonderland” “If everybody minded their own

    business, the world would go around a great deal faster than it does.”
  8. – Ilya Grigorik, Web Performance Engineer, Google “Performance is not

    just milliseconds, frames and megabytes. It’s also how these milliseconds, frames and megabytes translate to how the user perceives the application”
  9. –Martin Heidegger, German philosopher “…time persists merely as a consequence

    of the events taking place in it [space]” Perception Management http://goo.gl/9wXHL9
  10. EVENT MARKERS Perception Management EVENT1 start Event Marker end Event

    Marker inner Event Marker start end|start end
  11. LIMITATIONS When process is really long and there is no

    chance to make user think differently Perception Management
  12. –basic principle of psychology “If you can not change the

    situation, change the attitude” Tolerance Management
  13. Tolerance Management Dynamic Determinate “Designing and Engineering Time”, Steven C.Seow.

    © 2008 Pearson Education Inc. Provides periodic current status during mid-process Projects completion by work units or time Static Indeterminate Doesn’t project completion Does not provide any info during mid-process Download file blah-blah.mov (25GB)? Cancel Download Files scanned: 1250 Viruses found: 55 Your porn will be downloaded in less than 1 second. PLEASE wait Class A Class B Class D Class C
  14. TIME ANCHORS MATRIX 1 2 3 5 10 15 10

    20 30 Tolerance Management
  15. Tolerance SUMMARY Deliver objectively fast; If not possible to deliver

    fast, make user think it is fast; If it is really long process, make user want to wait. Perception Operation