39th International Conference on Software Engineering
May 26, 2017 | Buenos Aires, Argentina
Impact-Driven Process Model Repair
(Journal-First ACM TOSEM Paper, DOI: 10.1145/2980764)
Artem Polyvyanyy 1,*, Wil M. P. van der Aalst
1 Queensland
2
2,1, Arthur
H. M. ter Hofstede 1,2, and Moe T. Wynn 1
University of Technology, Brisbane, Australia
Eindhoven University of Technology, Eindhoven, The Netherlands
* Presenting/corresponding author
Deviances…
Artem Polyvyanyy | May 26, 2017 | Impact-Driven Process Model Repair | ICSE 2017
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Conformance Checking
perfect alignments
t2
b
p1
t1
real-world traces
t3
p3
p2
c
p5
a
t4
p4
d
t5
a b c
γ1 = a b c
a d e
γ2 = a d e
t1 t2 t3
t1 t4 t 5
e
designed traces
move on trace
a b x e≫
γ3 = a b ≫ ≫ c
t1 t2
t3
0 + 0 +1 + 1 + 2 = 4
synchronous move
a b x≫e
γ4 = a b ≫ c ≫
t1 t2
move on model
a≫b x e
γ5 = a d ≫ ≫ e
t3
0 + 0 +1 +2 +1 =4
t1 t4
t5
0 +3 +1 +1 + 0 = 5
cost(γ3)=cost(γ4)=4 and cost(γ5)=5; γ3 and γ4 are optimal alignments!
Artem Polyvyanyy | May 26, 2017 | Impact-Driven Process Model Repair | ICSE 2017
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Process Model Repair
a≫e
a b x≫e
γ4 = a b ≫ c ≫ γ6 = a d e
x t6
t2
b
p1
t1
p2
t3
p3
a
c
t1 t2
p5
t7
t4
d
p4
t3
t1 t4 t5
0 0 1 2 1
t5
e
insert
0 3 0
skip
=7
R=({x},{d})
Note the problem with x!
a b x≫e
γ7 = a b x c ≫
t1 t2 t6 t3
0+0 +0 +2 +1 = 3
a≫b x e
γ9 = a τ ≫ ≫ e
t1 t7
t5
a≫e
γ8 = a τ e
t 1 t7 t5
0+ 0 +1 +1+ 0 = 2
0+ 0 + 0 = 0
γ8 and γ9 are optimal alignments!  = 2
Artem Polyvyanyy | May 26, 2017 | Impact-Driven Process Model Repair | ICSE 2017
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Towards Optimal Repair
simulating repair via “free” moves
t2
b
p1
t1
p2
t3
c
p3
p5
a≫e
a≫b x e
γ10 = a d ≫ ≫ e γ11= a d e
t5
t1 t4
t5
t 1 t4 t5
e
0 0 1 0 0
0 0 0
x t6
R=({x},{d})
=1
a≫b x e
γ12 = a τ ≫ x e
a≫e
γ8 = a τ e
a
t7
t4
d
p4
t1 t7
t6 t5
t1 t7 t5
0+ 0 +1 +0+ 0 = 1
0+ 0 + 0 = 0
γ8 and γ12 are optimal alignments!
=1
Note no problem with x!
Artem Polyvyanyy | May 26, 2017 | Impact-Driven Process Model Repair | ICSE 2017
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Optimal Repair (Theorem 5.3)
R=({x},{d})
t2
b
p1
t1
p2
a
There exist optimal alignments between
the traces and the repaired model which:
t3
c
p3
p5
t7
t4
d
p4
t5
(ii) “Fulfill” the repair recommendation,
e.g., γ8 and γ12 contain no “bad”
moves (x,≫) and (≫,d).
e
x t6
a≫b x e
γ12 = a τ ≫ x e
t1 t7
(i) Demonstrate that the traces fit the
repaired model “at least as good” as
they fit the original model;
t6 t5
a≫e
γ8 = a τ e
t1 t7 t5
0+ 0 +1 +0+ 0 = 1
0+ 0 + 0 = 0
γ8 and γ12 are optimal alignments!
=1
Note no problem with x!
Artem Polyvyanyy | May 26, 2017 | Impact-Driven Process Model Repair | ICSE 2017
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One More Example
t2
p7
b
p9
f
t11
t7
p3
g
p2
p1
t8
t5
t3
t1
a
p6
p8
t9
p10
p11
d
p4
t10
p5
c
t4
h
t6
e
9x
10 x
7x
9x
2x
6x
All deviations
cost one Peso!
2x
Artem Polyvyanyy | May 26, 2017 | Impact-Driven Process Model Repair | ICSE 2017
 = 120
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A Possible Repair
t2
t13
b
f
t15
p9
p7
p3
p2
p1
t5
t3
t1
a
t7
p8
d
t4 p5
p4
p10
p11
e
x
t17
t6
t10
e
h
R = ({f,e,x},{c,f,g})
insert
t11
t9
p6
t16
t14
f
g
c
t12
t8
skip
Artem Polyvyanyy | May 26, 2017 | Impact-Driven Process Model Repair | ICSE 2017
 = 47
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Another Possible Repair
t2
t12
t13
b
e
f
p7
p1
t1
a
d
p2
t15 t3
p3
t4
p5
p4
t8
p9
f
t5
t7
p8
t9 p10
t11
g
t17
c
p11
p6
t14
e
t18
h
t16
t13
t6
t10
e
R = ({f,e},{g,d,e,c})
insert
skip
Artem Polyvyanyy | May 26, 2017 | Impact-Driven Process Model Repair | ICSE 2017
 = 33
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Towards Optimal Repair Recommendation
t12
t2
x
b
p3
p1
a
t4
p4
p7
d
p2
t15 t3
t1
t5
t8
f
t7
p8
t9 p10
g
p5
R = ({f,x},{d,e,c,h})
p9
t11
t14
f
t17
c
insert
p6
p11
t18
 = 25
f
t16
implemented
heuristics
t13
t6
t10
e
h
skip
costs of repair
recommendation
numbers of discovered
recommendations
numbers of alignment
computations
Artem Polyvyanyy | May 26, 2017 | Impact-Driven Process Model Repair | ICSE 2017
deviation costs
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Conclusion and Future Work
In this work, we …
 Defined, and proposed a solution to, the optimal process model repair problem
 Defined, and proposed several (approximate) solutions to, the optimal repair
recommendation problem
 Developed a publicly available tool that implements all the invented techniques,
https://svn.win.tue.nl/repos/prom/Packages/SelectivePRepair/Trunk/release/
 Reported on lessons learned from experiments with real-world data, e.g.,
for small repairs proposed heuristics perform just as well as brute-force
Possible avenues for future work include:





Case studies to better understand requirements of process model repair
Aesthetic process model repair
Repair heuristics with guarantees
Repairs based on other conformance data structures
Repairs that go beyond trace fitness
Let’s work together:
 Engage into research collaborations with us
 Write your master and/or PhD thesis with us (scholarships available)
Artem Polyvyanyy | May 26, 2017 | Impact-Driven Process Model Repair | ICSE 2017
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