Post on 28-Jan-2015
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COGNITIVE ANALYSIS OF WEB SITE NAVIGATION
Aimee Maree Forsstrom BAppComp
Post Graduate Research Student
Southern Cross University
School of Information Technology
Research performed under the supervision of Dr Graham Cooper
HUMAN COGNITIVE ARCHITECTURE
Image from http://education.arts.unsw.edu.au/staff/sweller/clt/
PLUS OR MINUS TWO THE MAGICAL NUMBER SEVEN The Magical Number Seven, Plus or Minus Two: Some
Limits on Our Capacity for Processing Information *
Short-term memory is restricted to just a few bits of information, this famous paper by George A Miller showed among other things how chunking could be employed to increase the restricted capacity of short-term memory.
*originally published in The Psychological Review, 1956, vol. 63, pp. 81-97 http://www.musanim.com/miller1956/
COGNITIVE LOAD THEORY
Cognitive load refers to the total amount of mental activity imposed on working memory at an instance in time.
This theory suggests that learning happens best under conditions that are aligned with human cognitive architecture.
Sweller, J., Instructional Design in Technical Areas, (Camberwell, Victoria, Australia: Australian Council for Educational Research (1999).
THE THREE MAIN TYPES OF COGNITIVE LOAD
Intrinsic cognitive load; Cannot be changed, this is due to the inherent difficulty associated with the information presented.
Extraneous cognitive load; Unnecessary cognitive load generated by the manner in which information is presented to learners and is under the control of designers (Cooper 1998).
Germane cognitive load; devoted to the processing, construction and automation of schemata (long term memory)” (Sweller 1999).
WITH COGNITIVE LOAD THEORY WE CAN REDUCE THE REQUIRED MENTAL EFFORT
When intrinsic cognitive load is low (simple content) sufficient mental resources remain
If the intrinsic cognitive load is high and the extraneous cognitive load is high total cognitive load will exceed.
Modifying instructional materials to engineer a lower level of extraneous cognitive load will facilitate learning.
COGNITIVE LOAD THEORY FOCUSES ON THE ROLE OF WORKING MEMORY IN THE LEARNING PROCESS
1. Working memory is extremely limited.2. Long term memory is essentially unlimited.3. The process of learning requires working
memory to be actively engaged in the comprehension of instructional material to encode into long term memory.
4. If the resources of working memory are exceeded then learning will be ineffective.
WHY WEB SITE NAVIGATION AND CLT?
As we navigate and learn our way through a web site we are interacting with and processing information
With the uptake of the web and the use of the web for business applications Navigation becomes more important to our efficient use of the web
MAIN WAY WE ACCESS INFORMATION – THE INTERNET
Web Site Navigation is Instructional Design Navigation is the instruction we use to locate
and move our way through a web site
NOT JUST STATIC BUT INTERACTIVE
The web has become Interactive No longer do we just surf/browse for
information But we interact with it and perform tasks
TASK DRIVEN NAVIGATION
With the rise of content management systems most websites these days are maintained by task driven interaction
Websites such as Twitter, facebook, bebo, linkedin, myspace are task driven not browse and search
We visit these websites to perform tasks and interact with the information
All this interacting changes the way we navigate around the web
ALL THIS INFORMATION CAN OVERLOAD OUR MEMORY
* Image from http://my.opera.com/englishlearning/blog/shor-term-memory
CAN WE ANALYSE IF PEOPLE HAVE INTERPRETED INFORMATION ON A WEB SITE?
Yes, this is where Cognitive Load Theory and Cognitive Analysis comes into play...
We don't just test if people enjoy and can use the website but we access how much information they have been able to process whilst interacting with it.
HOW DO WE PROVE INSTRUCTIONAL DESIGN IS BETTER
We run Controlled Experiment/s We take two groups of people One with the normal instruction (Control
Group) One with the changed instruction
(Experiment Group) We then look at the test results to see if
there is any statistical difference between the groups
If there is a statistical difference then the instructional change has benefited the interpretation of that information
EXAMPLE OF COGNITIVE LOAD WEB BASED EXPERIMENT
Game was designed to mimic task driven navigation
Two groups where used with different navigation types
Navigation design change looked into was CSS position:fixed (use of static menus)
EXPERIMENT DESIGN
1. Participants where taken through a navigation game (Random Facts Game)
2. Asked to complete a mental effort survey3. Asked to complete a “Fill in the Facts”
questionnaire from the random facts learnt in the game
4. Ask to perform a rebuild of the navigation menu (to show uptake of schema)
5. Asked to complete a usability survey and provide quantitative feedback
PRELIMINARY RESULTS FROM EXPERIMENT
The experiment group was more efficient in time for navigation steps, statistical significance found.
From the “Fill in the Facts” questionnaire we can see a statistical difference in the overall scores out of 17 questions, the experiment group scored higher in 14 and in all the harder questions.
From the Navigation Schema rebuild we can see a statistical difference in overall schema rebuild
In qualitative analysis 47% of the control group complained about the navigation whilst only 17% complained in the experiment group
WHAT DOES IT HELP US UNDERSTAND
From this research we can see a trend that if we change the web site navigation to adhere to cognitive load then people are able to take in the information more
We can form a conclusion that the group with better navigation had a lower incidence of cognitive over load and hence were able to interpret the information and also interact with more elements of the information
Some statistical differences found and trends present which present the need for further research into this effect
WHY IS COGNITIVE ANALYSIS NEEDED
Task Driven Navigation not just seek and find Web as become a hub of activity where we work
not just play More business is being done online, more people
are forced to interact with websites for there work Stop the guess work, are people taking in and
interacting with the information on our web sites
Examples of sites that could use Cognitive Analysis Government portal sites where access to worthwhile
information is why people visit them Content Management Systems (example Drupal
Admin Menu) Task driven and business based web applications
NOW THAT WE HAVE PASSED THE “WOW” FACTOR OF THE WEB, IT IS THE TIME FOR US AS WEB ENGINEERS TO ENSURE THAT THE USER EXPERIENCE IS PARAMOUNT.
NO LONGER CAN WE JUST DESIGN WEB SITES FOR US OR FOR THE BUSINESS BUT WE NEED TO CONSIDER HOW PEOPLE ARE INTERACTING WITH AND INTERPRETING OUR INFORMATION.
AIMEE MAREE FORSSTROM 2009