[M2] 
classical theories 
cognitive modeling
roles of theory
theory as paradigm 
that which underpins 
research design
theory as a lens 
that which may inform our 
understanding of the 
phenomenon under 
investigation
theory as new knowledge 
that which may emerge 
from our study
roles of theory in HCI
descriptive 
explanatory 
predictive 
prescriptive 
generative
what other 
conceptualisations did you 
find when going over your 
assignments?
classical theories
(raw) cognitive psychology 
(applied) basic research 
cognitive modeling
but let’s focus on cognitive 
modeling
direct manipulation
direct manipulation relates to 
distance and engagement
distance between one’s 
thoughts and the 
requirements of the system 
under use
engagement as in the feeling 
that one is directly 
manipulating the objects of 
interest
theory of action
gulf of 
execution
gulf of 
evaluation
the gulf of execution 
represents the difficulty the 
user has in translating a 
psychological goal into a 
physical action
for example, the goal learn more about 
avocados is purely psychological 
the user of a hypertext system on the WWW will 
need to see the available links, recognize the 
appropriate choice, and use the mouse to point 
and click on that link 
thus, in order to learn more about avocados, the 
user needs to execute a set of physical steps
the gulf of evaluation 
represents the user's 
difficulty in evaluating 
whether the response of the 
computer system meets the 
desired goal
in the previous example, the user would need to 
perceive the system response, examine the 
resulting node, and assess whether it presented 
the proper information about avocados
Keystroke-Level Model
KLM quantifies operations 
such as… 
K Press a key or button 
P Point to a target on the 
display 
H Home hands on input device 
D Draw a line segment 
M Mentally prepare for an action 
R (system response time)
Goals, Operators, 
Methods, Selectors
goals are what the user wants to achieve and 
can be broken down into subgoals 
operators are actions performed in service of a 
goal and can be perceptual, 
cognitive or motor acts 
methods are sequences of operators and 
subgoal invocations accomplishing 
a specific goal 
selection rules represent the user’s knowledge 
of which method should be applied
GOMS is good at 
modeling goal-directed 
tasks
GOMS is good for… 
comparing different designs 
building a help system 
parametric analysis 
profiling
GOAL: DELETE-FILE 
. GOAL: SELECT-FILE 
. . [select: GOAL: KEYBOARD-TAB-METHOD 
. . GOAL: MOUSE-METHOD] 
. . VERIFY-SELECTION 
. GOAL: ISSUE-DELETE-COMMAND 
. . [select*: GOAL: KEYBOARD-DELETE-METHOD 
. . . PRESS-DELETE 
. . . GOAL: CONFIRM-DELETE 
. . GOAL: DROP-DOWN-MENU-METHOD 
. . . MOVE-MOUSE-OVER-FILE-ICON 
. . . CLICK-RIGHT-MOUSE-BUTTON 
. . . LOCATE-DELETE-COMMAND 
. . . MOVE-MOUSE-TO-DELETE-COMMAND 
. . . CLICK-LEFT-MOUSE-BUTTON 
. . . GOAL: CONFIRM-DELETE 
. . GOAL: DRAG-AND-DROP-METHOD 
. . . MOVE-MOUSE-OVER-FILE-ICON 
. . . PRESS-LEFT-MOUSE-BUTTON 
. . . LOCATE-RECYCLING-BIN 
. . . MOVE-MOUSE-TO-RECYCLING-BIN 
. . . RELEASE-LEFT-MOUSE-BUTTON] 
*Selection rule for GOAL: ISSUE-DELETE-COMMAND 
If hands are on keyboard, use KEYBOARD-DELETE-METHOD, 
else if Recycle bin is visible, use DRAG-AND-DROP-METHOD, 
else use DROP-DOWN-MENU-METHOD

IFI7159 M2

  • 1.
    [M2] classical theories cognitive modeling
  • 2.
  • 3.
    theory as paradigm that which underpins research design
  • 4.
    theory as alens that which may inform our understanding of the phenomenon under investigation
  • 5.
    theory as newknowledge that which may emerge from our study
  • 6.
  • 7.
    descriptive explanatory predictive prescriptive generative
  • 8.
    what other conceptualisationsdid you find when going over your assignments?
  • 9.
  • 10.
    (raw) cognitive psychology (applied) basic research cognitive modeling
  • 11.
    but let’s focuson cognitive modeling
  • 12.
  • 14.
    direct manipulation relatesto distance and engagement
  • 15.
    distance between one’s thoughts and the requirements of the system under use
  • 16.
    engagement as inthe feeling that one is directly manipulating the objects of interest
  • 17.
  • 19.
  • 20.
  • 21.
    the gulf ofexecution represents the difficulty the user has in translating a psychological goal into a physical action
  • 22.
    for example, thegoal learn more about avocados is purely psychological the user of a hypertext system on the WWW will need to see the available links, recognize the appropriate choice, and use the mouse to point and click on that link thus, in order to learn more about avocados, the user needs to execute a set of physical steps
  • 23.
    the gulf ofevaluation represents the user's difficulty in evaluating whether the response of the computer system meets the desired goal
  • 24.
    in the previousexample, the user would need to perceive the system response, examine the resulting node, and assess whether it presented the proper information about avocados
  • 25.
  • 26.
    KLM quantifies operations such as… K Press a key or button P Point to a target on the display H Home hands on input device D Draw a line segment M Mentally prepare for an action R (system response time)
  • 28.
  • 29.
    goals are whatthe user wants to achieve and can be broken down into subgoals operators are actions performed in service of a goal and can be perceptual, cognitive or motor acts methods are sequences of operators and subgoal invocations accomplishing a specific goal selection rules represent the user’s knowledge of which method should be applied
  • 30.
    GOMS is goodat modeling goal-directed tasks
  • 31.
    GOMS is goodfor… comparing different designs building a help system parametric analysis profiling
  • 32.
    GOAL: DELETE-FILE .GOAL: SELECT-FILE . . [select: GOAL: KEYBOARD-TAB-METHOD . . GOAL: MOUSE-METHOD] . . VERIFY-SELECTION . GOAL: ISSUE-DELETE-COMMAND . . [select*: GOAL: KEYBOARD-DELETE-METHOD . . . PRESS-DELETE . . . GOAL: CONFIRM-DELETE . . GOAL: DROP-DOWN-MENU-METHOD . . . MOVE-MOUSE-OVER-FILE-ICON . . . CLICK-RIGHT-MOUSE-BUTTON . . . LOCATE-DELETE-COMMAND . . . MOVE-MOUSE-TO-DELETE-COMMAND . . . CLICK-LEFT-MOUSE-BUTTON . . . GOAL: CONFIRM-DELETE . . GOAL: DRAG-AND-DROP-METHOD . . . MOVE-MOUSE-OVER-FILE-ICON . . . PRESS-LEFT-MOUSE-BUTTON . . . LOCATE-RECYCLING-BIN . . . MOVE-MOUSE-TO-RECYCLING-BIN . . . RELEASE-LEFT-MOUSE-BUTTON] *Selection rule for GOAL: ISSUE-DELETE-COMMAND If hands are on keyboard, use KEYBOARD-DELETE-METHOD, else if Recycle bin is visible, use DRAG-AND-DROP-METHOD, else use DROP-DOWN-MENU-METHOD