1 Evaluation of the E3 Process modelling language and tool Letizia Jaccheri and Tor Stålhane Department of Computer and Information Science Norwegian University of Science and Technology Trondheim

2 Motivation a lot of PMLs and tools have been developed few evaluations have been performed

3 This talk E 3 : Environment for Exerimenting and Evolving software processes The Experiment Problem statement Experiment planning Experiment operation Presentation of the data Experiment analysis Conclusions

4 E start 1993 ISPW7 OO Coad & Yourdon 1994 Iveco OO Coad & Yourdon 1995 E 3 version 1 X C++ Kernel + views 1996 Olivetti E 3 version Politecnico Sw Eng course E 3 version NTNU students Ericsson E 3 version E 3 version 2 java Filters and properties

5 Predefined classes and associations

6 E 3 p-draw  Creation of templates by interconnecting classes and associations  Creation of instance process models  automatic instantiation  extension of objects and links

7 Filters Workspaces: drawing canvas: place and modify filters to workspaces to hide and show the entities of interest inheritance derived Simple. Composite. Recursive composite. Customization

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10 This talk E 3 : Environment for Exerimenting and Evolving software processes The Experiment Problem statement Experiment planning Experiment operation Presentation of the data Experiment analysis Conclusions

11 Problem statement 40 students 10 groups PM exercise

12 Planning H1: For the purpose of creating software process models, the E 3 PML is easier to use than a standard modelling language and tool the average number of modelling problems  1 that students encounter when using E 3 (PML and tool) is less than the average number of modelling problems they encounter when using IDEF0  2 Null hypothesis H0:  1 =  2

13 Operation Decisions Students rather than industry Ask the students to list problems rather than questionaires Students did not get extra teaching around E 3 Challenge Motivating students

14 Problems IDEF0 What was complicate with the modelling activity was to decide whether a given influence on a process should be interpreted as control or input to the process We had problems to specify resources to activities and subactivities precisely. We have used the general concept resources as we did not have available more precise concepts. We found that the constraint that one must have between 3 and 3 subactivities in a IDEF0 model limiting in a case in which we wanted to have two sub-activities.

15 Problems IDEF0 (2) Sometimes there can be very many arrows between the different boxes even if we only have 6 boxes. Such big quantity of arrows makes the models more difficult to follow and to manage. Some activities has many inputs and this makes the model over-complex. It is difficult to decompose activities. We had problems to distinguish between constrains and input. The model soon becomes over-complex, especially when one has many inputs and outputs

16 Problems E3 The problem is the overview. Although with a rather simple process like this one, it is difficult to maintain control. The fact that one must model both horizontal and vertical relationships in addition to document flow contributes to this.

17 Presentation of data IDEF E300200

18 Conclusions As a conclusion from our data, we are 90% sure that there will be less modelling problems when using E3 PML than when using IDEF0 for the purpose of creating software process models Risks All the problems are equal Normal distribution approximation although we have few data Six of ten observation are identical and 0

19 Further work We need more data Register time Register the seriousness of each problem Is it at all useful to compare two tools? organization versus experiment setting Students for research evaluation

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