Software Measurement and Function Point Metrics

Size: px

Start display at page:

Download "Software Measurement and Function Point Metrics"

Tracy Wilkins
5 years ago
Views:

1 Software Measurement and Function Point metrics in a broad software contractual agreement Roberto Meli Tommaso Iorio Roma Marzo 2005

2 Different types of pricing approaches: dis/advantages Total Fixed Cost for Specified Product (also called Turnkey Supply), Total Variable Cost for Time & Material Total Variable Cost for Released Product based on unitary fixed costs SMEF 2005 Roma / Marzo /20

Variable Cost for Time & Material Total Variable Cost for Released

3 Fixed Price Function Point: Problem no manager can accept to be penalized on his/her project while other projects are valued for the profitability provided to the overall program due to the desired uncertainty of the open contract in terms of requirements (what, how, when and how much) needed to maximize flexibility of the outsourcing choice, there is no guarantee that the final mix of actual required projects is exactly the one on which the productivity average has been estimated FP calculated as backfiring from costs or other technical metrics.. SMEF 2005 Roma / Marzo /20

to maximize flexibility of the outsourcing choice, there is no guarantee that the final mix of actual required projects is exactly the one on which

4 What is the right price-fixing model, then, to be applied to general contracts and open contract? And more, what is the workflow that, based on the supplier-customer interaction, leads to the right price? SMEF 2005 Roma / Marzo /20

5 Price evaluation: a transactional issue Market Transactions External Productivity Customer Internal Productivity Requirements Constraints Solution(TCQ 2 ) Negotiation Requirements Constraints Quantity Quality Effort Time Staff Unitarystaff cost Discount Total cost Contract Supplier Internal Productivity SMEF 2005 Roma / Marzo /20

Requirements Constraints Quantity Quality Effort Time Staff Unitarystaff cost Discount

use of a (transparent) methodological model in a contract: advantages data and price-fixing mechanisms can be shared between the parties of the contract by using the model, the haggling tends to

6 use of a (transparent) methodological model in a contract: advantages data and price-fixing mechanisms can be shared between the parties of the contract by using the model, the haggling tends to shift away from the price and more on the key factors that enhances price accountability the model gives the opportunity to use the embedded know-how even to beginners. Customer Model Supplier SMEF 2005 Roma / Marzo /20

price and more on the key factors that enhances price accountability the model gives the opportunity to use

7 Suggested solution A model (1) to objectively measure the software supply, in terms of the value perceived by the Customer (measured in terms of price ) A model (2) to estimate the software supply cost incurred by the Supplier (measured in terms of cost ) SMEF 2005 Roma / Marzo /20

price ) A model (2) to estimate the software supply cost incurred by the

8 Methodological reference context The model complies with ISO international standards (FSM Definition of concepts) and transposed by IFPUG into the White Paper: Framework for Functional Sizing issue 1.0 -Sept. 2003) The model is based upon the most objective metrics correlated with experimental data and is predicated upon a thorough evaluation of key project factors, The model applies mainly to large software projects involving new developments and enhancements, where efforts and costs are mainly driven by the functional size, as shown by benchmarking statistics, such as ISBSG database statistics. SMEF 2005 Roma / Marzo /20

2003) The model is based upon the most objective metrics correlated with experimental data and is predicated upon a thorough evaluation of key project factors,

9 Our methodological reference context exclude Activities with no functional impacts: Feasibility Studies ; Application Porting MAC (corrective maintenance ) Application Installation or deployment ; System activities; small-scale projects SMEF 2005 Roma / Marzo /20

(corrective maintenance ) Application Installation or deployment ;

10 Next slides Model (1): from Requirements to Price Model s description Workflow description Model (2): from Requirements to Cost Model s description (cenni) Workflow description (in other papers/publications) SMEF 2005 Roma / Marzo /20

to Cost Model s description (cenni) Workflow description (in

11 Requirements to Price cycle SMEF 2005 Roma / Marzo /20

12 Step of Model to determine Price 1. Measurement of released and worked functionalities (IFPUG UFP and/or Early & Quick Function Point) 2. For each adjustment factor evaluation of impact level (for example very low, low, normal, high, very high, extremely high), and calculating the total adjustment factor (TAF) through the multiplication of all values 3. Computation of the Business Function Point (BFP = WFP x TAF ) 1. Price computation (BFP * Unitary Average Price ) SMEF 2005 Roma / Marzo /20

For each adjustment factor evaluation of impact level (for example very low, low, normal, high, very high, extremely high), and

13 What is the Unitary Average Price for a BFP? It is simply the Unitary Average Market Price of a Standard Unadjusted Function Point when: No reuse or replication is made and Average (market) application complexity Average (market) technical and quality factors Average (market) productivity factors Are impacted SMEF 2005 Roma / Marzo /20

when: No reuse or replication is made and Average (market) application complexity

14 Quantitative definition of Technical and Quality Factors Model 1: the workflow 1/3 Set the Model Quantitative definition of Productivity Factors Customer Table to be shared with Suppliers una-tantum at start-up the factors can be selected/quantified by internal analysis (for example Delphi method) and/or referring other cost models (for example Cocomo) SMEF 2005 Roma / Marzo /20

una-tantum at start-up the factors can be selected/quantified by internal analysis (for example

15 Model 1: the workflow 2/3 Set the Contract Functional Requirements Definition Non Functional Requirements evaluation of impact level for each factors Customer Feasibility Study / Request For Proposal / Step for each Project/Contract Set the impact level for each factors, based up on characteristics of the project SMEF 2005 Roma / Marzo /20

Study / Request For Proposal / Step for each Project/Contract Set the impact level for

16 Model 1: the workflow 3/3 Contract Governance Estimate BFP SW realization BFP measures Invoicing Supplier Estimation Approval Measurements Approvals Customer SMEF 2005 Roma / Marzo /20

17 Requirement to Cost cycle REQUIREMENTS Company Technicals and Quality Fattori Tecnici Factors e di Qualità Fattori di Produttività aziendali Company Productivity Factors Costo Hour Orario Cost Resources Risorse SW Life Cycle Ciclo di Vita CALCULATE Adjusted Effort Total Adjustment Factor CALCULATE MEASURE MISURA FP DETERMINE DETERMINAZIONE WFP ESTIMATE CALCOLO Impegno Most Likely medio Effort Complessit Complexity à Reuse Riuso and e replicazione Replication ISBSG DB Company aziendale DB COST SMEF 2005 Roma / Marzo /20

Total Adjustment Factor CALCULATE MEASURE MISURA FP DETERMINE DETERMINAZIONE WFP ESTIMATE CALCOLO Impegno Most Likely medio Effort

18 Step of Model to determine Cost 1. Measurement of released and worked functionalities (IFPUG UFP and/or Early & Quick Function Point) 2. Definition of the features dealing with: 1. Technical and Qualitative dimension (Technical Adjustment Factors) 2. Business Productivity (Productivity Factors) 3. Estimation of managerial variables (most likely effort and duration) 4. Most likely effort is weighted up against business parameters 5. Cost evaluation SMEF 2005 Roma / Marzo /20

Definition of the features dealing with: 1. Technical and Qualitative dimension (Technical Adjustment Factors) 2.

19 Suggestions from past experiences How to select and evaluate Adjustment Factors Relationship between adjustment and risk factors Estimating and measuring effectively Ongoing Change Requests SMEF 2005 Roma / Marzo /20

adjustment and risk factors Estimating and measuring

20 Conclusions Two different points of view, two models: to determine price and to determine cost It is possible to integrate the models Worked and Business Function Points to overcome the limits and problems of Function Point fixed-price SMEF 2005 Roma / Marzo /20

Worked and Business Function Points to overcome the limits and

21 SMEF 2005 Roma / Marzo /20

A (new) unified model of custom software costs determination

A (new) unified model of custom software costs determination in contracts. Roberto Meli (CEO) [email protected] - www.dpo.it April 2015 SOFTENG 2015 1 Preliminary considerations The discipline and practice