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Tools Requirements Engineering Safety & Security Engineering Quality Engineering Software Engineering Continuous, Agile & Lean Engineering Empirical and Behavioural Software Engineering 

Rethinking Productivity in Software Engineering Dagstuhl, 2017-03-06/07 Stefan Wagner What’s Productivity? Terminology and Influencing Factors 

You can copy, share and change, film and photograph, blog, live-blog and tweet this presentation given that you attribute it to its author and respect the rights and licenses of its parts. based on slides by @SMEasterbrook und @ethanwhite 

The Chimera of Software Productivity Efficiency Effectiveness Productivity Performance Profitability Quantity Functionality Quality LOC, FP, … Intangibility of Software Product Lines Reuse Automation Tools Model-Driven Implementation Test Maintenance Team Workplace Improvement, Measurement, Comparison 

A Timeline of Productivity Research in Software Engineering 1968 First experimental studies 1975 1987 1979 Albrecht’s Function Points 1981 1986 Jones’ Programming Productivity 2005 2000 2000s Story Points 2010s 

What is Productivity? 

Open Issues – Quantity, Quality and Value Productivity of knowledge work […] has to aim first at obtaining quality […]. Only then can one ask: „What is the volume, the quantity of work?” Peter F. Drucker Quality is a complex and multifaceted concept. It is also the source of great confusion… David A. Garvin […] the value of the software […] cannot be measured by the cost of building it, but by how well it meets the needs of the user. And […] I have never, even one time, seen exactly the same business problem. Jon “Maddog” Hall 

Productivity • Difficult for knowledge work • Could consider – Quality – Timeliness – Project success – Customer satisfaction – Innovation • No broadly applicable and accepted means for productivity measurement Productivity = Output Input Units of products Units of material Person- hours Size 

Profitability Profitability = Revenue Cost Price inflation Cost inflation 

Performance Vision and Strategy Internal Business Processes Financial Customer Learning and Growth To satisfy our shareholders, what business processes must we excel at? 

The PE Model Purpose Quality Functionality Effort Effectiveness Efficiency Productivity Profitability Performance Inflation, pricing Customer perception [based on Tangen, 2005] 

What general factors influences productivity? 

Technical Factors Doc. Match to Life-Cycle N. Use of Modern Dev. Pract. Programming Language Use of Software Tools Hardware Concurrent Dev. Project Duration Effective and Efficient V&V Completemenss of Design Early Prototyping Platform Volatility Process Maturity Architecture Risk Resolution Reuse Development Flexibility User Interface Product Quality Software Size Main Storage Constraint Execution Time Constraints Developed for Reusability Product Complexity Database Size Required Software Reliability Precedentedness # of publications 2 3 2 6 3 7 3 4 2 3 2 2 1 1 3 1 2 1 2 3 7 3 7 2 Dev. Env. Process Product Wagner, S. and Ruhe, M. (2008) A Systematic Review of Productivity Factors in Software Development. In Proc. 2nd International Workshop on Software Productivity Analysis and Cost Estimation (SPACE 2008). 

Soft Factors Avg. Team Size Req. Stability Schedule Telecom. Facilities Physical Separation Time Fragmentation E-Factor Proper Workplace Manager App. Experience Manager Capability Lang. and Tool Experience Platform Experience Applications Experience Progammer Capability Analyst Capability Developer Temperaments Support for Innovation Communication Team Cohesion Turnover Clear Goals Sense of Eliteness Team Identity Camaraderie Fairness Respect Credibility # of publications 4 6 5 1 2 3 3 7 9 4 1 1 8 10 7 7 8 7 2 3 2 1 4 2 5 6 10 Project Cap. & Exp. Team Culture Environment Corp. Culture 

Do personality and programming styles influence productivity? 

Developers differ in their performance, decision making and working habits. 

The Big Five Personality Test 5 Closed-Minded Open to New Experiences Disorganised Conscientious Introverted Extraverted Disagreeable Agreeable Calm/Relaxed Nervous / High-Strung Openness to Experience Conscientiousness Extraversion Agreeableness Emotional Stability 

Cox and Fisher’s Theory Task Situation Individual internal external Influence Programming Styles like personality like experience Programming Context’s Factors 

Top-down & depth-first Top-down & breadth-first Bottom-up & depth-first Bottom-up & breadth-first Programming Styles 

Study Design Age Gender Programming Experience Attitude towards Programming Personality Factors Human Factors Programming Styles ? ? Programming Performance Programmer Quality (self-assessed) Project and Code Quality (Grade) Code Quality (Static Analysis Warnings) 

Significant Correlations (All Positive) Programming Performance Number of Programming Languages (Experience) Age Academic Achievement Depth-First Programming Style Conscientiousness (Personality) Years at University (Experience) Large Revisions (Programming Style) 

Limitations • Self-developed questionnaire to operationalise some styles • Self-assessed survey • Mainly students in second year of studies • Volunteer bias • Correlations do not need to be cause/effect 

There is a significant relation between personalities of programmers and their programming styles. 

So how do we measure and improve it? 

The ProdFLOWTM Approach Ruhe, M. and Wagner, S. (2008) Using the ProdFLOW™ Approach to Address the Myth of Productivity in R&D Organizations In Proc. 2nd International Symposium on Empirical Software Engineering and Measurement (ESEM '08). ACM. 

„ The most important contribution management needs to make in the 21st century is […] to increase the productivity of knowledge work and the knowledge worker. Peter F. Drucker 

Prof. Dr. Stefan Wagner e-mail [email protected] phone +49 (0) 711 685-88455 WWW www.iste.uni-stuttgart.de/se Twitter prof_wagnerst ORCID 0000-0002-5256-8429 arXiv http://arxiv.org/a/wagner_s_1 Institute of Software Technology Slides are available at www.stefan-wagner.biz. Joint work with Manfred Broy, Florian Deissenboeck, Melanie Ruhe, Zahra Karimi, Ahmad Baraani-Dastjerdi, Nasser Ghasem-Aghaee 

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