22 дек. 2009 г.

Jakob Nielsen — Short-Term Memory and Web Usability

  “The human brain is not optimized for the abstract thinking and data memorization that websites often demand. Many usability guidelines are dictated by cognitive limitations.”

Designing for Brainpower Limitations

  “When it comes to abstract thinking, humans have extremely limited brainpower. For example, short-term memory famously holds only about 7 chunks of information, and these fade from your brain in about 20 seconds.”

  “Short-term memory limitations dictate a whole range of Web design guidelines:
  • It's a common misconception that limited short-term memory implies that menus should be similarly limited to 7 items. It's fine to have longer menus (if needed), because users don't have to memorize the full list of menu items.
  • Response times must be fast enough that users don't forget what they're in the middle of doing while waiting for the next page to load.>
  • Change the color of visited links so that users don't have to remember where they've already clicked.
  • Make it easy to compare products, highlighting the salient differences {...}
  • Offer help and user assistance features in the context where users need them so they don't have to travel to a separate help section and memorize steps before returning to the problem at hand.”

Individual Differences

  “Although the average human brain is better equipped for mammoth hunting than using websites, we're not all average. In fact, there are huge individual differences in user performance: the top 25% of users are 2.4 times better than the bottom 25%.
   At the extreme, only about 4% of the population has enough brainpower to perform complex cognitive tasks such as making high-level inferences using specialized background knowledge. Most likely, you're in this elite group. And, worse yet, so are many other members of your Internet team.”
  “It's a good overall mnemonic to design for cavemen and their literal-minded and limited-capacity brains. After all, your paying customers are only one step out of the cave.”

Комментариев нет:

Отправить комментарий