Slides of my presentation at COGNISE workshop at CAiSE conference, 3 June 2019, Rome, Italy

1. 1/17 | www.janclaes.info
Jan Claes and Gilles Vandecaveye
The impact of confusion on syntax errors
in simple sequence flow models in BPMN

2. 2/17 | www.janclaes.info
Context – introductory statements
 Conceptual models are useful
 Conceptual models contain errors
 Syntax errors are the easiest to study objectively
 Syntax errors are the least relevant to study
 To study errors, study the creation process
 Process-data is available for ‘process models’

3. 3/17 | www.janclaes.info
Problem statement
About syntax errors
in simple sequence flow models
 Different levels exist: clear error versus confusion
 What is the relation between both?
 What can we learn from this?

4. 4/17 | www.janclaes.info
How many syntax errors?
Send PO to
factory
Send PO to
warehouse
Update
contact info
Update
financial info
Close
file
Gateway combines
join and split
semantics
ERROR
Clearly not allowed
by the specification
IRRESOLUTION
No consensus whether it
is allowed/what it means
CONFUSION
Allowed, but
not recommended

5. 5/17 | www.janclaes.info
Syntax error or not?
Close
file
If the model is
finished: YES
If the model in not
finished: NO

6. 6/17 | www.janclaes.info
Error or not?
Send PO to
warehouse
Update
contact info
Update
financial info
Close
file
(wrong symbol)(missing symbol)
DEFINITE ERRORUNCERTAIN ERROR

7. 7/17 | www.janclaes.info
Data collection
 Tool = Cheetah Experimental Platform
 Task = build sequence flow model
from structured textual description
 Language = subset BPMN constructs
 start event + end event
 XOR gateway + AND gateway (split + join)
 Activity + edge (including label)
 Participants = 126 master students
Business Engineering
at Ghent University in 2015

8. 8/17 | www.janclaes.info
Identified syntax issues

9. 9/17 | www.janclaes.info
Measures per modeling session

10. 10/17 | www.janclaes.info
Measures per modeling operation

11. 11/17 | www.janclaes.info
Global results

12. 12/17 | www.janclaes.info
What about timing?

13. 13/17 | www.janclaes.info
Conditions for causality
 Theoretical argumentation
Confusion influences cognitive load
Cognitive load influences effectiveness
 Observed correlation
Not always significant though (inaccurate measures)
Poor external validity though
 Temporal precedence
Poor external validity though
? Control for third variables
Maximum attention for equal conditions between
subjects, but no guarantees

14. 14/17 | www.janclaes.info
Which confusion causes which error?

15. 15/17 | www.janclaes.info
Conclusions
 No solid proof, but input for further research
 H1. Using multiple end events causes the modeler to
forget to close all paths in the model
 H2. Modelers are not always aware of when using
implicit gateways is allowed and when not
 H3. Having multiple start and end events causes the
modeler to forget adding the postponed paths for which
a gateway was already created

16. 16/17 | www.janclaes.info
Conclusions
 No solid proof, but support for existing guidelines
 Use 1 start and 1 end event (7PMG)
 Use no more than 2 start and end events (10PMG)
 Model as structured as possible (7PMG, 10PMG, ASP)
 Use design patterns to avoid mismatch (10PMG)
 Use explicit representation (CSP)
 Limit the difference in the number of input/output flows
between splits and joins (QI)
 Use of textual annotation (CSP)
 Naming guidance (CSP)

17. 17/17 | www.janclaes.info
 Do you have any questions?
 Do you have feedback?
Thanks for you attention!
Jan Claes
jan.claes@ugent.be
www.janclaes.info