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SEKE 2012 Proceedings - Knowledge Systems Institute

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equirement was considered “false positive” when it was<br />

wrong (e.g. a misunderstanding about the business<br />

processes) or in the case that it could not have been<br />

extracted through business processes models. This<br />

indicator is considered relevant because it prevents the<br />

specification of requirements that are not in conformity<br />

with the identified needs extracted from the business<br />

processes.<br />

The experiment goal using the GQM (Goal/<br />

Question/Metric) paradigm [2] is presented in Table I.<br />

TABLE I. GOAL OF THE 1 ST .EMPIRICAL STUDY<br />

Analyze<br />

The REMO technique<br />

For the purpose of Characterizing<br />

Effectiveness and adequacy of the<br />

With respect to identified requirements using the<br />

business processes<br />

From the point of view Software Engineering Researchers<br />

A requirements elicitation from a w eb<br />

In the context of based system having as basis business<br />

processes models.<br />

Hypotheses: the study was planned and conducted in order<br />

to test the following hypotheses (null and alternative,<br />

respectively):<br />

H01: There is no difference in t erms of effectiveness in<br />

using the REMO technique to elicit requirements regarding<br />

business processes.<br />

HA1: The REMO technique presented a difference in the<br />

effectiveness indicator, when compared to a traditional<br />

approach.<br />

H02: There is no difference in terms of adequacy of the<br />

identified requirements when using the REMO technique and a<br />

traditional approach.<br />

HA2: The REMO technique presented different results<br />

regarding the adequacy of the identified requirements, when<br />

compared to a traditional approach.<br />

Context: the study was carried out in M ay 2011 with<br />

undergraduate students from senior-level undergraduate<br />

Computer Science and Information System courses. These<br />

students were attending Analysis and Design class at the<br />

Federal University of Amazonas (UFAM). All the subjects had<br />

tutorials about Business Process Modeling and Requirements<br />

Elicitation. As the object study we used the business processes<br />

modeling of part of the processes. This part described the<br />

management activities of the discipline “Final Project”.<br />

Preparation: 30 students played the role of system analysts<br />

and signed a consent form. The subjects also filled in a<br />

characterization questionnaire, with questions regarding their<br />

practical experience. This questionnaire allowed us to identify<br />

that, despite being undergraduate students; many of them had<br />

experience in system analysis in the industry. An ordinal scale<br />

was used to measure their experience: Low, Medium and High.<br />

Three subjects were classified with High experience (having<br />

participated in f ive or more development projects), sixteen<br />

subjects were classified with medium experience, and the<br />

remaining eleven with low experience (with theoretical<br />

knowledge and no previous experience in industrial system<br />

analysis). The categorization results are shown in Table II.<br />

Execution: the subjects received: (a) an execution guide<br />

with tasks, (b) the business context document containing the<br />

BPMN processes modeling, and (c) requirements register<br />

spreadsheet. Furthermore, the group that used the REMO<br />

technique received the additional documentation: the<br />

technique’s heuristics document. The group that did not use the<br />

REMO technique used a traditional approach to identify the<br />

requirements, using the knowledge used in the previous<br />

trainings and the processes modeling, as suggested by [4].<br />

The study was carried out by each group in different days.<br />

The first day Group 1 used the traditional approach and the<br />

second day Group 2 used REMO technique. Each group had<br />

120 minutes to carry out the requirements elicitation based on<br />

the business processes models. We collected 13 and 15<br />

spreadsheets from the traditional approach and the REMO<br />

technique approach respectively. Readers must take note that 2<br />

students did not show up the first day, leaving the groups<br />

unbalanced. We carried out an outlier analysis in order to<br />

balance the groups. After finishing the study, we created a<br />

unique requirements list, in order to discriminate the<br />

requirements. The analyst responsible for the development of a<br />

system for automating final projects control carried out the<br />

discrimination process. The discrimination meeting was carried<br />

out to identify which requirements were considered inadequate<br />

(e.g. misunderstandings about the business processes).<br />

Results and Quantitative Analysis: Table II p resents the<br />

results of the requirements registers per group of subjects.<br />

Readers must take note that we used a total of 29 known<br />

requirements from the processes models, in order to calculate<br />

the effectiveness degree of the requirements.<br />

TABLE II.<br />

Group 1 (TRADITIONAL)<br />

REQUIREMENS RESULTS PER GROUP OF SUBJECTS<br />

Group 2 (REMO)<br />

Exp Sub IIR FP EI (%) AI (%) Exp Sub IIR \ FP EI (%) AI (%)<br />

H<br />

A09 14 5 31.03 64.29 H R03 21 12 31.03 42.86<br />

A13 21 10 37.93 52.38 R04 21 9 41.38 57.14<br />

A03 19 8 37.93 57.89 R06 24 9 51.72 62.50<br />

A04 32 17 51.72 46.88 R07 14 4 34.48 71.43<br />

M<br />

A08 32 19 44.83 40.63 M R08 21 11 34.48 47.62<br />

A10 26 13 44.83 50.00 R10 18 5 44.83 72.22<br />

A14 21 6 51.72 71.43 R11 19 8 37.93 57.89<br />

A15 28 10 62.07 64.29 R12 21 8 44.83 61.90<br />

A01 28 18 34.48 35.71 R02 12 4 27.59 66.67<br />

A05 7 6 3.45 14.29 R05 19 5 48.28 73.68<br />

L A07 12 6 20.69 50.00 L R09 23 8 51.72 65.22<br />

A11 29 17 41.38 41.38 R13 38 20 62.07 47.37<br />

A12 23 11 41.38 52.17 R14 24 17 24.14 29.17<br />

Legend: H – High; M – Medium; L – Low; Exp – Experience; Sub – Subjects;<br />

IIR –Initially Identified Requirements; FP – False Positives; AI – Adequacy<br />

Indicator; EI –Effectiveness Indicator.<br />

In order to validate these data we used the Mann-Whitney<br />

statistic method, which is supported by the SPSS Sta tistics<br />

v17.0 1 tool, and the boxplots analysis. Fig.2 shows the<br />

distribution of effectiveness per subject, per technique. The<br />

boxplots graph shows only a slight difference between the<br />

subjects who used the technique and those who did not use it.<br />

When we compared the two samples using the Mann-Whitney<br />

1 http://www-01.ibm.com/software/analytics/spss/<br />

35

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