described in previous section. The data necessary for
the application of the framework were mainly
collected by analysing the documentation, software
trackers, source code repositories and official web
sites of the project. Moreover, some other data were
obtained by analyzing the source code and using the
product itself. Finally, further data source considered
are some very useful web sites, such as
sourceforge.net, freshmeat.net and ohloh.net.
The “in vitro” nature of the experiment did not
allow a realistic evaluation of the efficiency, so it
has been left out. Tables 6, 7 and 8 synthesize the
obtained results. They list all the quality
characteristics and the score obtained for each of
them by applying the relevance indexes, also listed,
of both baseline EFFORT and its customized
framework.
Table 6 shows results regarding the quality of
Compiere software product.
It can be observed that Compiere product is
characterized by more than sufficient quality. With a
detailed analysis of the sub-characteristics, it can be
noticed that the product offers a good degree of
portability and functionality, excellent reliability and
sufficient usability. Concerning product quality, the
lowest value obtained by Compiere is related to the
maintainability.
With reference to the reliability, the
characteristic with higher score, a very satisfying
value was achieved by the robustness, in terms of
age, small amount of post release bugs discovered,
low defect density, defect per module and index of
unsolved bug. An even higher value was obtained
for the recoverability, measured in terms of
availability of backup and restore functions and
services.
Concerning maintainability, the lower score, it
was evaluated mainly using CK metrics (Chidamber,
1991), associated to the related sub-characteristics.
For instance, the medium-low value for testability of
Compiere depends on high average number of
children (NOC) of classes, number of attributes
(NOA) and overridden methods (NOM), as well as
little availability of built in test functions. Values of
cyclomatic complexity (VG) and dept of inheritance
tree (DIT) are on the average.
It was observed that global scores obtained with
the two different relevance criteria, are substantially
the same for Compiere product quality. There is just
a little negative variation considering both relevance
indexes. Moreover, a better characterization of some
aspects was done, knowing the application domain.
In fact, other metrics were considered, other than the
ones considered by the general version of EFFORT.
For that reason, Table 6 presents two columns of
scores: the “
BASELINE” one is obtained by
considering metrics from EFFORT general version
only, while the “
SPECIALIZED” column contains
results from the evaluation by means of all metrics
from the EFFORT customized version.
For instance, there are different scores for
adaptability and replaceability (and, consequentially,
for portability). In fact, the number of supported
DBMS and availability of a web client interface
were considered for the adaptability characteristic.
Whereas, availability of functionality for backup and
restore data, availability of backup services and
numbers of reporting formats have been taken into
account for the replaceability characteristic. Those
aspects are not significant for other kind of software
products.
In Table 7, data regarding community
trustworthiness are reported. In the case of Goal 2,
as well as in the one of Goal 3, the hierarchy of the
considered characteristics has one less level.
Moreover, aspects of this goal are completely
generalizable for all FlOSS projects so anything of
this part of the EFFORT framework changes, but the
relevance.
The score obtained by Compiere for community
trustworthiness is definitely lower with respect to
product quality. In particular, community behind
Compiere is not particularly active; in fact, average
number of major release per year, average number of
commits per year and closed bugs percentage
assume low values. Support tools are poorly used. In
particular, low activity in official forums was
registered. Documentation available free of charge
was of small dimension; while the support by
services results was more than sufficient, even if it
was available just for commercial editions of the
product. This reflects the business model of
Compiere Inc., slightly distant from traditional open
source model: product for free, support with fee.
This time the evaluation by means of the specialized
version of EFFORT (in this case consisting just of
different relevance pattern) gives better results for
the Compiere community. That is the main reason
for which the availability of support services was
considered more important than community activity,
in the ERP context.
As mentioned before, product attractiveness is
the quality aspect more dependent from operative
context of the product itself. In this case, it was
extended the relative goal with other four questions,
as explained in section 3.3. The aim was to
investigate how this can influence the evaluation.
EVALUATING THE QUALITY OF FREE/OPEN SOURCE ERP SYSTEMS
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