<!-- Task Match with users -->

Given the focus of users was remembering appointments and organizing
notes, then these are the areas the PDA should support in order to be
useful.  Secondly, given the limited writing space on both PDAs, they
are not about to be used for writing essays or taking class notes - the
keyboards are too small and slow to type on.  The primary activity left
is scheduling and random note taking.
<P>
Students took varied but simple approaches to this problem.  No one
used voicemail or answering machines actively.  E-mail was not a
large factor - it was checked infrequently (average twice a day: morning
and evening).
<P>
The Sony is very good at scheduling - unfortunately it is too big to carry
in a pocket (a separate carrying case is available), and the screen will
be scratched if it is flung into a carryall.  The Sony is obviously pitched
at someone who has more time and space than a hurried student.
The message function in the Sony is easy to use, but not immediately
applicable to law students.  They are quite happy to check their e-mail
once or twice a day, and have regular study group appointments (a scheduling
problem again).  Sketching, another MagicCap fort&eacute;, is of limited
applicability to law students - pen and paper do the job cheaper.
<P>
The Psion is not very creative at scheduling - it can fit a very short
description in for each hour.  The separate to do list is very useful though.
On the other hand, it takes less time to set up an appointment on the Psion.
The Psion is small enough to fit in a jacket pocket, and its flip-top casing
will protect it from the rigors of traveling in a student's bag. 
The Psion has better note taking capabilities, in that the keyboard can
be used for copying down small amounts of text without too much difficulty.
Sketching is non-existent on the ver. 3 Psion.


<!-- GOMS -->

<H3>Sony MagicLink</H3>

Targets on the MagicCap interface are approx. 2 cm across.  The screen
is about 15 cm across and 10 vertically. 
i.e. on average the stylus must move 7 cm from
its current position to a target.
The time to press a screen button (0.3 s) is more than the time to press a
keyboard key (0.1 s) because the whole hand has to move, plus the system
needs a good contact in order to register the press.
<P>
Also note that system response time can fluctuate a lot, depending on
the amount of data in the system and the most recent tasks performed.
<UL>
 <LI>   Goal: Make appointment for lunch with Bob.
 <UL>
  <LI>   Goal: Open appointment book (2.5 s)
  <UL>
   <LI>   Move pointer to lower left. (Fitts: 7 cm= 0.4 s)
   <LI>   Press DESKTOP button   (0.3 s)
   <LI>   Wait for desktop to appear (0.5 s)
   <LI>   Move pointer to middle right of screen. (Fitts: 15 cm= 0.5 s)
   <LI>   Press on the CALENDAR (0.3 s)
   <LI>   Wait for calendar to appear (0.5 s)
  </UL>


  <LI>   Goal: Find tomorrow (2.3 s total)
  <UL>
   <LI>   Goal: Find Today (1.2 s total)
   <UL>
    <LI>   Move pointer to upper right of screen (Fitts: 15 cm= 0.4 s)
    <LI>   Press TODAY button (0.3 s)
    <LI>   Wait for display to update (0.5 s)
   </UL>
   <LI>   Goal: Go to next day (1.1 s total)
   <UL>
    <LI>   Move pointer to upper middle of screen (Fitts: 5 cm= 0.3 s)
    <LI>   Press NEXT DAY ARROW (0.3 s)
    <LI>   Wait for display to update (0.5 s)
   </UL>
  </UL>


  <LI>   Goal: Make appointment (9.0 s total)
  <UL>
   <LI>   Goal: Highlight lunch time (1.6 s total)
   <UL>
    <LI>   Move pointer to 12 noon of time line (Fitts: 5/1 cm=0.3 s)
    <LI>   Press on 12 (0.3 s)
    <LI>   Wait for mark to appear (0.7 s)
    <LI>   Drag tip to 1 pm (Fitts: 1/1 cm=0.2 s)
    <LI>   Lift pointer (0.1 s)
   </UL>
   <LI>   Goal: Enter appointment (7.4 s total)
   <UL>
    <LI>   Wait for keyboard to appear (2 s)
    <LI>   Press keys with pointers "lunch w " (Fitts: 7/1 cm*8 char=3.2 s)
    <LI>   Press SHIFT toggle (Fitts: 7/1 cm= 0.4 s)
    <LI>   Press "B" (Fitts: 7/1 cm = 0.4 s)
    <LI>   Press SHIFT toggle (Fitts: 0.4 s)
    <LI>   Press "ob" (2*Fitts: 0.4 s)
    <LI>   Move pointer to lower right corner (Fitts: 7/1 cm= 0.4 s)
    <LI>   Press BOX-X to remove keyboard. ( 0.2 s)
   </UL>
  </UL>

 </UL>
</UL>
Total time:  2.5+2.3+9.0 = 13.8 s
<P>

<H3>Psion</H3>
Since the keyboard is fairly small, I take the keypress time somewhat
higher than the standard value: 0.2 s per keypress rather than 0.1 s.
<P>
Pressing the hotkeys located under the screen requires a Fitts move
(4 cm roughly to the key row, target size: 1 cm) and a press, giving
a hunt time of 0.3 s, and a peck time of 0.2 s, in total 0.5 s per hotkey.
The peck time is 0.2 s because the keys are harder to press than the normal
keyboard keys.
<UL>
<LI>    Goal: Make appointment for lunch with Bob tomorrow
 <UL>
 <LI>    Goal: Open agenda/scheduler (1.2 or 0.6 s)
 <UL>
  <LI>    Select:
  <UL>
   <LI>    Goal: Use arrow key method (1.1 s)
   <UL>
    <LI>        Press the SYSTEM hotkey (0.5 s)
    <LI>        Press RIGHT-ARROW button UNTIL AGENDA highlighted. (2 x 0.2 s)
    <LI>        Press ENTER (0.2 s)
   </UL>
   <LI>    Goal: Use hot key method (0.5 s)
   <UL>
    <LI>        Press the AGENDA hotkey (0.5 s)
   </UL>
  </UL>
  <LI>    Wait for display to update (0.1 s)
 </UL>

 <LI>    Goal: Find right time (0.5 or 2.4 s)
 <UL>
  <LI>    Goal: Find tomorrow
  <UL>
   <LI>    Select: 
   <LI>    if today is showing: (0.4 s)
   <UL>
    <LI>    Hold CTRL key, press RIGHT ARROW, release CTRL key. (0.2 + 0.2s)
<BR>            0.2 s for CTRL key, the 0.2 s for RIGHT arrow
   </UL>
   <LI>    if some other day is showing: (2.3 s)
   <UL>
    <LI>     Hold PSION key press J, release PSION key (0.2 + 0.2 s)
    <LI>     Wait for dialog box to appear (0.1 s)
    <LI>     Enter tomorrows date: <CODE>"11161994"</CODE> (8*0.2 s)
    <LI>     Press ENTER (0.2 s)
   </UL>
   <LI>     Wait for page to change (0.1 s)
  </UL>

  <LI>    Goal: Find lunchtime (noon-1 pm) (1.0 s)
  <UL>
   <LI>    Press DOWN ARROW until "12" selected. (5 * 0.2 s)
  </UL>
 </UL>

 <LI>    Goal: Enter Appointment (2.9 s)
 <UL>
  <LI>    Type "lunch w Bob" (11* 0.2 s + 0.2 s for shift key)
  <LI>    Press ENTER (0.2 s)
  <LI>    Wait for dialog box (0.1 s)
  <LI>    Press ENTER to confirm appointment. (0.2 s)
 </UL>

 </UL>
</UL>
Total time: 2.9 + 1.2 or 0.6 + 0.5 or 2.4 = 4.0 s (best) or 6.5 s (worst)
<P>
The Psion, while more complicated, is much faster than the MagicLink,
simply because it does not take so long to load its software components.  
The nifty interface of the Sony is simply too cumbersome for this sort
of operational task analysis.