StarOffice Calc v. MS Excel: - SVN

StarOffice Calc Usability Evaluation
Selecting Data
Range for a
Chart
Difficulty understanding
which cell range to
choose.
Conduct more
comprehensive testing
on chart functions.
Severity Metrics
We devised a four-point severity scale based on Jakob Nielsen’s severity ratings [2]. The scale
measures three main attributes of a usability problem: frequency, impact, and persistence.
Frequency refers to the percentage of participants affected by a given problem. Impact refers to the
ease with which a participant can overcome a given problem. Persistence refers to how able
participants are to overcome a given problem once they know about it. Each usability problem
receives a rating for each attribute. The severity ratings are detailed in Table 13.
Table 13. Severity Ratings
Frequency Impact Persistence
0 Occurs very rarely Minor annoyance Problem does not recur after
initial encounter.
1 Occurs in fewer than
10% of cases
2 Occurs in 10-50% of
cases
3 Occurs in more than
50% of cases
Little impact
Medium impact;
takes some time to
overcome
Great impact; takes
a disproportionate
amount of time to
overcome
Problem can occur after initial
encounter, but users
generally are able to avoid
problem.
Users often re-commit error
despite knowing about it.
Users are unable to avoid
encountering the problem
even though they know it will
occur. The system will not
allow them to bypass
problem.
Table 14 shows the four quantifiable usability problems discovered in the StarOffice Calc interface
and our ratings of these problems using the abovementioned scale.
Table 14. StarOffice Calc Severity Ratings
Frequency Impact Persistence Total Severity
Score
Finding and Applying 3 3 0 6
Cell Merge
Drawing and 2 2 0 4
Formatting Shapes
Inserting a Chart 2 3 2 7
Eklund, Feldman, and Trombley, 12/11/2001 32 of 54