think-cell technical report TC2003/01 A GUI-based Interaction ...

6.2 Case Study EVALUATION
Without specifying every detail of the user interaction at this point, I could
deduce the approximate number of required mouse moves and clicks. For more
plausible results, I distinguished easy mouse interactions (like selection of a single
element) and difficult mouse interactions (like multiple paste) and assigned them
2 seconds and 5 seconds time exposure, respectively. I did not take time for typing
text into account, but I did account for entering the text entry mode with one easy
interaction.
I applied this model to the slide that is shown in figure 9. The expert rating for
creating the layout of that slide was 15 minutes. Based on my simulation model,
using the smart grid and the solver, the layout could be specified in less than three
minutes. This translates to a speed-up factor of 5 which compares well to the factor
of 6 that was observed for chart design (Sect. 6.1.1).
6.1.3 Expected Over-All Speed-Up
Based on the findings presented in section 2.2.3, I projected my speed-up estimation
on chart design and slide layout to the over-all PowerPoint-related workflow in a
business consultancy. For the sake of the argument and to account for the fact
that my case studies are not statistically representative, I did not take the speed-up
factors of 6 and 5, but rounded off the estimated speed-up to 10
3 . Figure 47 shows
the result: In the chosen setting of a business consultancy, a performance gain of
about 40 % can be expected for PowerPoint with the think-cell add-in in comparison
to the plain PowerPoint.
Chart design
19.9%
Custom drawings
11.1%
Text entry at
160 chars/min
29.7%
Slide layout
39.3%
(a) Current time exposure (comp. Fig. 5(b))
Time savings
41.5%
Custom drawings
11.1%
Text entry
29.7%
Chart design
6.0%
(b) Expected time savings
Slide layout
Figure 47: The estimated time saved with think-cell chart and layout plugins over
all stages of the PowerPoint-related workflow is greater than 40 %.
6.2 Case Study
To the running prototype as described in the previous sections, I added some triv-
ial solver functionality that implements “optimal” layout by equidistant gridlines.
Hence, the prototype is already manoeuvrable and can serve as an evaluation of
the user interface, however the output is far from esthetically satisfying. The un-
derlying assumption is, of course, that with a real numerical solver the resulting
layout would appear natural and appealing. In this section, a simple case study is
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11.8%