Rahmat Bagas Santoso Diogo Satoru Aihara Vojtech Zbranek.
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Transcript of Rahmat Bagas Santoso Diogo Satoru Aihara Vojtech Zbranek.
Rahmat Bagas SantosoDiogo Satoru Aihara
Vojtech Zbranek
Motivation
• No one build software from the scratch.• Component based software development is a
prominent contemporary software development.
• Supported by many well-known frameworks and standards (Microsoft COM/DCOM, Enterprise JavaBean, Web service, etc).
• No (widely used) estimation technique for CBSD.
Problem
• Different decomposition
• Transferable component estimation
Warehouse Application
Stock
Supply
Sales & Order
FormWH App.
SpecificReport
CommunicationUser
Managemnt
Log
Project A Project B
Comp. A1Comp. A1 Estimation
Comp. A2Comp. A2 Estimation
Comp. A2Comp. A2 Estimation’ ( Usage? Upgrade? Known Facts?)
Comp. B1Comp. B1 Estimation
COTS Comp. C1 COTS Comp C1 Estimation
COTS Comp. C1
Approaches (1)
(*) T. Wijayasiriwardhane and R. Lai: “A Method for Measuring the Size of a Component-Based System Specification”
(**) R. K. Smith, A. Parrish, and J. Hale: “Cost Estimation for Component Based Estimation”
ProblemSize/Function
Points Estimation
Size / Function
Points
Effort Estimation (COCOMO)
Effort
T. Wijayasiriwardhane and R. Lai Approach - 2008 (*)
R. K. Smith, A. Parrish, and J. Hale Approach - 1998 (**)
Approaches (2)
Author Title Year Type ContextT. Ellis COTS Integration in Software Solutions
- A Cost Model1995 Cost COTS
C. Abts Extending the COCOMO II Software: COCOTS Model (Integrated in COCOMO II Book)
2004 Cost COTS
P. Naunchan & D. Sutivong
Adjustable Cost Estimation Model for COTS-Based Development
2007 Cost COTS
John Kammelar A Sizing Approach for OO-environments
2000 Size OO Based -> Component Based
J. Verner &G. Tate
A Software Size Model 1992 Size 4GL - problem dependent
Size Estimation for CBSDComponent Point
• FP-like approach• Usage of CBS Specification
– Written in UML
• Integration of two techniques– Class Point (FP for Object Oriented systems)– Component Complexity measurement
Component PointEstimation Process
Analyse CBSS UMLand
Classify Components
Evaluate Interface and Interaction Complexity of Components
Evaluate Component Complexity and Get
Unadjusted Component Points
Find the Value Adjustment Factor and Calculate the Final Component
Points
UML List of Components
Classificationof
ComponentsInterface Complexity
Interaction Complexity
Unadjusted Component
Points
Final Component
Points
Interface Complexity
• Two types– Internal Logical Files– External Input Files
• Parameters– Number of Operations– Number of Parameters
NONP
<20 20-50 >50
1 Low Low Average
2-5 Low Average High
>5 Average High High
Type Low Average High
ILF x7 x10 x15
ELF x5 x7 x10
Interaction Complexity
• For each operation, multiply:– Interaction Frequency– Complexity Measure
• Interaction Complexity = sum for all operations
#Interactions(operation)
#Interactions(interface)IF=
CM(D,L) = L + S(CM(Di,L+1))
Component Complexity
1. Find the component complexity
2. Count the Component Points
ITCIIFCI
<5 5-8 >8
<2 Low Low Average
2-3 Low Average High
>3 Average High High
Type Low Average High
DC x3 x6 x10
UC x4 x7 x12
SC X4.5 x7 X11.5
Interface Complexity
# of InterfacesIFCI =
Interaction Complexity
# of InteractionsITCI =
Adjust Component Points
1. Find the Value Adjustment Factor
2. Adjust the Component Points
General System Characteristics
Data and online communication Distributed processing
System / component performance Development rigidity
User friendliness System complexity
Installability Operability
Maintanability Multi-site use
System / component reliability System / component portability
Component immaturity Lack of component vendor support
VAF = 0.65 + (0.01*Degree of Influence)
CP = Unadjusted CP * VAF
Degree of Influence
No Influence Strong Influence0 5
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Effort Estimation for CBSD (1) : COCOMO Model
• Basic COCOMO Model by Boehm• General effort model:
E = a (EDSI)h x (EAF) Legend:
E – Effort [man-moths] a,h – Constant given by developing mode EAF – Effort adjustment factor (15 cost factors) EDSI – Estimate of Delivered Source Instruction
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Effort Estimation for CBSD (2): COCOMO Model
• Example:Effort given from basic COCOMO for program with 8500 LOC:
E = a (EDSI)h x (EAF) = = 3.2 (8.5)1.05 x 1 = 30 MM
• Boehm also adopted the Intermediate COCOMO Model to apportion cost of individual components
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Effort Estimation for CBSD (3):Intermediate COCOMO Model Example
• Intermediate COCOMO:– Inputs:
• LOC = 8500• EbasicCOCOMO =MMNOM= 30MM
CMMNOM - nominal component man-month
Component EDSI % of total CMMNOM
Comp#1 2000 23,4% ?Comp#2 3000 35,3% ?Comp#2 3500 41,2% ?
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Effort Estimation for CBSD (3): Intermediate COCOMO Model Example
• Intermediate COCOMO:– Inputs:
• LOC = 8500• MMNOM= 30MM (from basic COCOMO)
Component EDSI % of total CMMNOM
Comp#1 2000 23,4% 7,06Comp#2 3000 35,3% 10,60Comp#2 3500 41,2% 12,36
– Count:• EDSI/MMNOM=8500/30=283
• CMMNOM=EDSIcomp/(EDSI/MM)NOM
CMMNOM - nominal component man-month
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Effort Estimation for CBSD (4): Intermediate COCOMO Model Example
• After CMMNOM Effort Adjust Factor (EAF) is calculated for each component individually
• The EAF is applied to CCMNOM for each component!!! Consider variance among the cost factors for
various component!New adjusted MM estimate for each component
CMMADJ:
CMMADJ = (CMMNOM)(EAF)
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Effort Estimation for CBSD (5): Intermediate COCOMO Model Example
CMMADJ = (CMMNOM)(EAF)
Component EDSI % of total CMMNOM EAF CMMADJ
Comp#1 2000 23,4% 7,06 0.89 6.28Comp#2 3000 35,3% 10,60 1.13 11.98Comp#2 3500 41,2% 12,36 1.05 12.98
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Effort Estimation for CBSD (6):
• Even this improvements over monolithic approach fails to capture relevant parameters in CBSD
• Inspection CBSD found out wealth of new parameters not directly captured in COCOMO adaptation
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Effort Estimation for CBSD (7): An Augmented COCOMO Model
• Work with– Within-project experience– Team size
• Model formula:
HOURS = α + β1(COCOMO) + β2(PREV) + β3(PROG)
– HOURS – number of hours devoted for component– COCOMO – result of intermediate COCOMO– PREV – number of comp. previously worked on (Within-project experience)– PROG – size of component development team
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Effort Estimation for CBSD (8): Current studies identifying parameters
• For effort estimation is captured by a three dimensional view of the development process– x axis captures the component under development– y axis represents time– z axis the programmers on the project
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Effort Estimation for CBSD (9): Current studies identifying parameters
• Research for metrics by passing planes through the three dimensional model
• “contextual planes” - By passing a plane through the model that is perpendicular to an axis, we capture the “context” related to two other axis
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Effort Estimation for CBSD (10): Current studies identifying parameters• This view of CBSD allows an effort estimation model to
examine metrics and effort factors at a fine-grained level of detailed that is not captured by traditional effort estimation models
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Effort Estimation for CBSD (11): Current studies identifying parameters• Using this concept of components, time units
and programmers, we can derive a suite of metrics that characterizes the effect of scheduling on CBSD. We have developed formal definitions of these metrics.
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Effort Estimation for CBSD (12): Identifying parameters
• Intensity - The ratio of the quantity of actual time spent on a component to the number of time units scheduled for the component.
• Concurrency - The degree to which multiple programmers are working simultaneously on a single component.
• Fragmentation - The degree to which a single programmer is working simultaneously on multiple components.
• Component Project Experience - The number of components that have been completed as part of the project prior to work beginning on a particular component.
• Programmer Project Experience - The number of components that have been previously completed by the programmers assigned to a particular component.
• Team Size - The number of programmers assigned to a particular component.
Conclusions
• Although CBSD is widely used, but no eminent size/cost estimation method available yet.
• Some proposals to do estimation CBSD are already published but most of them still in research. Furthermore they need industry validation.
• Most estimation proposal on CBSD is in analogy with how other disciplines do the extension of the traditional estimation.
• More interesting result may come in the future with the support of validation.
Thank You
• Questions & Answers