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Jorge Muñoz-Gama
Josep Carmona
Universitat Politècnica de Catalunya
(Barcelona, Spain)
A fresh look at Precision in Process Conformance
Precision in Process Conformance2
Outline
15 Sep 2010
Process Mining and Process Conformance Motivation Approach
General Approach Implementation Results Extensions
Future work Conclusions
Precision in Process Conformance3
Process Mining
15 Sep 2010
* www.processmining.org
Precision in Process Conformance4
Conformance Dimensions
15 Sep 2010
Fitness
Precision
Generalization
Structure
How much of the observed behavior is
captured by the model
Minimal structure which clearly reflect the
behavior
Models with minimal behavior to represent
accurately the log
Overly precise models which overfit the log
Precision in Process Conformance5
Outline
15 Sep 2010
Process Mining and Process Conformance Motivation Approach
General Approach Implementation Results Extensions
Future work Conclusions
Precision in Process Conformance6
Related Work
15 Sep 2010
Precision in the literature Most related work Rozinat et al. Information System 33 (2008) Metric for Precision in Petri Nets Computation of Follows and Precedes relations (Always,
Never, Sometimes) of Model and Log.
Measurement based on discrepancies in Sometimes relations Model relations require a model space state exploration
Coverability
Graph
Precision in Process Conformance7
Motivation
15 Sep 2010
Goals and Requirements Precision Dimension Petri Nets Avoid the complete state space exploration Effort needed to obtain an accurate model Fine-level precision Locate the precision inconsistencies
Precision in Process Conformance8
Process Conformance and Refinement
15 Sep 2010
Petri Net
A B DA C D
Event Log
MDT
ETC Precision
Metric
Conformance
(Precision)
AC
BD
Locate the inconsistencies
Measure the inconsistencies
Precision in Process Conformance9
Outline
15 Sep 2010
Process Mining and Process Conformance Motivation Approach
General Approach Implementation Results Extensions
Future work Conclusions
Precision in Process Conformance10
General Idea: Escaping Edges
15 Sep 2010
ModelBehavior
LogBehavior
ModelBehaviorEscaping
Edges
Precision in Process Conformance11
Conformance Route Map
15 Sep 2010
ModelStates
LogStates
Traversal
MDT
Metric
AC
BD
A B DA C D
Petri Net
Event Log
Precision in Process Conformance12
Log and Model States
15 Sep 2010
Log Incorporate state information in the log
(Aalst et al. Software and Systems Modeling, 2009) Past, Unlimited and Sequence
Model Markings of the Petri Net
Precision in Process Conformance13
Model States and Mapping
15 Sep 2010
Not all the reachable markings (could be infinite)
Only Markings with a Log State mapped on
Log and Model States Mapping i.e., reached marking after replay state prefix
A E
D
C
Bp1 p2 p3
A B Ep4 s1
p1
s2
p2
s3
p3
s4
p4p5
0 1 0 0 1…
0 1 0 0 n
p1 p2 p3 p4 p5
Markings not explored
Precision in Process Conformance14
Log-guided Traversal
15 Sep 2010
Log-guided Traversal of Model Behavior Allowed Tasks :
i.e., actions enabled in that moment
Reflected Tasks : i.e., actions really executed (thus, annotated in the
log)
A E
D
C
Bp1 p2 p3 p4
A E
D
C
Bp1 p2 p3 p4
A B EA C E
<p2>BCD
A B EA C E
BC
Precision in Process Conformance15
Traversal (2)
15 Sep 2010
Escaping Edges : i.e., enabled actions not executed Precision discrepancies
A E
D
C
Bp1 p2 p3 p4
A B EA C E
BCD
BC
D
Precision in Process Conformance16
Precision Metric
15 Sep 2010
Take into account the Escaping Edges
Between 0 (imprecise) and 1 (precise) More frequent traces, more weight in the metric Independent of Structural dimension Global precision Localizability
AP
HZ
Q
IA H I ZA P Q Z
Precision in Process Conformance17
Minimal Disconformant Traces (MDT)
15 Sep 2010
Localizability of precision inconsistencies
i.e., Minimal traces indicating where the model starts to deviate from the log
Algorithm to compute all MDT using Escaping Edges
Refinement
AnalysisPrecisionMDT
A EA B E
C D P Q
A D
C
B
Refined Petri Net
Precision in Process Conformance18
Outline
15 Sep 2010
Process Mining and Process Conformance Motivation Approach
General Approach
Implementation Results Extensions
Future work Conclusions
Precision in Process Conformance19
Implementation
15 Sep 2010
ProM 6 Framework
ETConformance Plug-In
Precision in Process Conformance20
Outline
15 Sep 2010
Process Mining and Process Conformance Motivation Approach
General Approach Implementation
Results Extensions
Future work Conclusions
Precision in Process Conformance21
Results
15 Sep 2010
Precision in Process Conformance22
Results (2)
15 Sep 2010
Precision in Process Conformance23
Outline
15 Sep 2010
Process Mining and Process Conformance Motivation Approach
General Approach Implementation Results
Extensions Future work Conclusions
Invisible Tasks Duplicate Tasks States as Markings Non fitting
donedonein progressin progress
Precision in Process Conformance24
Invisible Tasks
15 Sep 2010
AH
I
C
Bp3
p4
A C
Which Sequence? A H C ? A I C ?
INDETERMINISM
(Transitions associated with no event)
Precision in Process Conformance25
Invisible Tasks (2)
15 Sep 2010
Invisible Coverability Graph
Solutions Union of
Enabled Lazy Invisibles * One path only Shortest
Invisible Path *
<1, ω, 0>
<0, ω, 1>
<1, 0, 0>
<0, 0, 1>
Inv1
Inv3
Inv2
A,B
A,DC
A,C
A
D
B
X
XC
X
*Rozinat et al. Information System 33 (2008)
Precision in Process Conformance26
Duplicate Tasks
15 Sep 2010
Which Task? B ? B ?
INDETERMINISM
Solutions e.g. Look-ahead
AB
B
D
C
... A B C ...
(Several Transitions associated with the same event)
Precision in Process Conformance27
Variant: States as Markings
15 Sep 2010
States as Prefix
States as Markings
A
B
CA B C
A
B
CA B C
<p1><p2><p3>
C B
p1 p2 p3
2Escaping Edges
NO Escaping Edges
Precision in Process Conformance28
Variant: Non fitting models
15 Sep 2010
Symmetric to the Escaping Edges (Ee) Log Escaping Edges (LEe): The points where
the log deviates from the model
Fitness instead of Precision
ModelBehavio
r
LogBehavio
r
ModelBehavio
r
Escaping
Edges
LogEscaping
Edges
Precision in Process Conformance29
Outline
15 Sep 2010
Process Mining and Process Conformance Motivation Approach
General Approach Implementation Results Extensions
Future work Conclusions
Precision in Process Conformance30
Future Work: Refinement
15 Sep 2010
Refinement
Breaking Concurrencie
s
Supervisory Control
AC
BD
Petri Net
Refined Petri Net
A D
C
BEvent Log
A EA B E
MDT
A EA B E
B H J G
Precision in Process Conformance31
Concurrencies in the model but not in the log Break the model concurrency with a restriction, e.g. a
place
Structural Concurrency Best effort overapproximation for general Petri Nets Exact for live and bounded Free Choice systems Polynomial Algorithm
Kovalyov and Esparza , Proc. Intl. Workshop on Discrete Event Sytems, 1996
Future Work: Breaking Concurrencies
15 Sep 2010
A B C DA D
C
B
Precision in Process Conformance32
Supervisory Control
15 Sep 2010
Supervisory Control in Process Mining Santos et al. Supervisory Control Service (2010)
Supervisor
Model
MDT MDT Abstraction
Refined Model
Precision in Process Conformance33
Conclusions
15 Sep 2010
New technique for precision between Petri nets and Log.
Avoids complete models state space exploration.
Metric based on the effort needed to obtain a precise model.
MDT, indicating the points where the model starts to deviates from the log.
Approach implemented as plug-in of ProM 6.
Precision in Process Conformance34
Thank You
15 Sep 2010
Thank You for Your Attention