884e643a3ff33fd8b0e7f652eb69ea7d.ppt
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CS 501: Software Engineering Lecture 23 People 1 1 CS 501 Spring 2008
Administration Quiz 4 Tuesday, April 22 2 CS 501 Spring 2008
Business Models: Free-Lance Software Development You and a few friends create a company to develop software. You are offered a contract to write bespoke software. How much should you charge per hour? You plan to work 40 hours a week for 50 weeks of the year and want to earn $50, 000. Hourly rate = $50, 000 / (40 x 50) = $25 But. . . 3 CS 501 Spring 2008
Free-Lance Software Development Salary Benefits (including taxes) Rent, equipment, etc. Fees, services, etc. Travel and misc. TOTAL EXPENSE Hours worked less administration less marketing BILLABLE HOURS $50, 000 $15, 000 $10, 000 $100, 000 2, 000 400 350 1, 250 Hourly rate = $100, 000 /1, 250 = $80 4 CS 501 Spring 2008
Free-Lance Software Development You MUST have a contract with the customer. It may be a simple letter or a complex agreement. What should it contain? Are you being paid by the hour? Or by completion of the task? What acceptance tests will be done? Who decides when the job is done? Who owns the software? What licenses does the other party have? Who provides hardware, software that is required, supplies, etc. ? When will you get your money? 5 CS 501 Spring 2008
Business Model: Packaged Software Example of fixed and variable cost: • The initial development cost of a software product is $1 million. • The cost of packaging and distribution of each copy is $5. • Technical support costs average $15 per copy. • The package sells for $200 per copy. Fixed cost = $1 million Variable cost = $20 6 CS 501 Spring 2008
Fixed and Variable Costs: Profit or Loss Revenue $1. 5 M Costs $1. 0 M $0. 5 M 2, 500 7 5, 000 Unit sales 7, 500 CS 501 Spring 2008
Profit or Loss? If you sell 7, 500 copies do you make a profit of $350 K? • Did you borrow money to cover the start-up period? How much interest did you pay? • What about taxes? Cash flow • When will you be paid (always late)? • When do you have to pay your bills? Risk 8 • What extra costs do you have if the product is a year late? • What if you only sell 5, 000 copies? • If you increase the price, does your revenue go up or down? CS 501 Spring 2008
Business Models: In-house Computing Departments Organization • Central computing department, reporting through a Chief Information Officer • Decentralized model with computing distributed across the organization, reporting to operational units Expertise • Full in-house design and software development expertise • Outsourcing with project management in-house 9 Even if development is contracted to consultants, software houses, etc. , organizations need considerable in-house expertise to oversee the work. CS 501 Spring 2008
Software Houses A software house is a company that creates software for other organizations, e. g. , S. A. P. , Infosys, Oracle/People. Soft, etc. Business is a mixture of: consulting packages (solutions) custom software maintenance education Because large sums of money involved, emphasis is on contracts, visible processes, well-defined deliverables, and acceptance tests. 10 CS 501 Spring 2008
Outsourcing Concept: Contract with software house to develop software for an organization. Benefits: Software house may be better organized to recruit staff, and manage projects. Clear visibility. No need to build an inhouse team for a single project. Small organization cannot have all the expertise to cover a complex project. Disadvantages: Software house may not have the same goals as the organization (e. g. , incentive to prolong project, to build software that can be used in other projects). 11 Organizations need considerable in-house expertise to oversee the work. Must not over-estimate the expertise of the software house. CS 501 Spring 2008
Business Models: Bespoke Software is tailored to specific environment • Very large applications (e. g. , air traffic control) • Small-scale, highly specific applications (e. g. , Cornell dormitory keys) Development options • Software is written in-house • Software is written by contractor Product may be owned by supplier or customer. Maintenance may be in-house or by contractor. 12 CS 501 Spring 2008
Business Models: Package with Modifications Software house develops general purpose package Client • Licenses package • Source code is modified for client's specific needs Business consideration • Modifications may be by software house or in-house team • Maintenance may be by software house or in-house team Legal issues include: access to source code, ownership of modifications, avoiding being locked-in to a supplier 13 Examples: Corporate pay-roll systems, accounting systems for small businesses, etc. CS 501 Spring 2008
Business Models: Package Without Modifications Package Licensed in Binary Form Only • Package typically has many options, including configuration options • Package may be a self-contained application (e. g. , Turbo. Tax), a component to incorporate in applications (e. g. , Oracle database system), or system software (e. g. , Windows) Legal considerations: there is a clear distinction between a package (license from supplier) and application. Examples: Database systems, mathematical packages, etc. 14 CS 501 Spring 2008
Business Models: Embedded Systems Software bundled with hardware product Product is seen by the user as a hardware product, even if the software development is the major part of the cost Examples: Cell phone, GPS, automobile engine control, i. Pod 15 CS 501 Spring 2008
Unorthodox Business Models: Shareware • Producer writes a software package. • Distribution is open, but requests a fee, e. g. , $50. • Users who pay the fee may get a small benefit, e. g. , no message when they start up the software. • Some people have received substantial revenue this way. 16 CS 501 Spring 2008
Unorthodox Business Models: Open Source Examples: Linux, Apache, Perl, Hadoop, Fedora • Market leaders • High quality General model • Shared development • A central developer provides overall coordination • Distribution of source code is completely open Personal examples: • TCP/IP for Vax/VMS • Python 17 CS 501 Spring 2008
Notes on Open Source Software may be open source, but packaging and services can be profitable businesses (e. g. , Red Hat, IBM Linux). For more information about open source software, see: http: //www. opensource. org/ Many open source software projects are managed on the Source. Forge system: http: //sourceforge. net/ 18 Open source software development and distribution is particularly suitable for organizations such as universities who develop software for the public good. CS 501 Spring 2008
Open Source License Sample open source license (GNU General Public License): http: //www. gnu. org/licenses. html • Free redistribution • Source code available • Derived works permitted • Integrity of the author's source code • No discrimination against persons or groups • Protection against unscrupulous patents • No discrimination against fields of endeavor • License must not be specific to a product * 19 CS 501 Spring 2008
Software Development Staff • Professional staff are the major cost of software • Professional staff vary greatly in productivity => Ability => Education and training => Motivation => Interaction with colleagues and leaders => Work environment • 20 People are productive when happy and happy when productive CS 501 Spring 2008
Managing People Theoretical • Organizational behavior • Industrial psychology Group behavior • Cognitive fundamentals Economic motivation 21 CS 501 Spring 2008
Maslow's Hierarchy of Needs Self-realization needs Esteem needs Social needs Safety needs Physiological needs 22 CS 501 Spring 2008
Software is Built by Teams • • Team members may include: developers (from trainee to expert) domain experts graphic or interface designers software librarians testers etc. • 23 Best size for a team is 3 to 8 people Teams must have: administrative leadership (manager) technical leadership (may be the manager) CS 501 Spring 2008
Administrative Leader (Manager) • • Resources Budgets Space, facilities Equipment • 24 Personnel Assigning tasks Hiring, promoting, etc. Project management Relationships with other teams and clients Project plan and schedule CS 501 Spring 2008
Group Working How time is spent 20% non-productive 30% working alone 25 50% interaction with others CS 501 Spring 2008
Communication • • Staff meetings (non-technical) • 26 Informal Kitchen, smokers' doorway, after work, etc. Walkabout (tours) Ad hoc meetings Technical meetings Facilitation Record of decisions CS 501 Spring 2008
Communication Management of teams dispersed across locations • Creating a team sense Example: Tektronics • Face-to-face meetings Occasional but regular, e. g. , once or twice per year Entire team, including support staff • Remote meetings on a regular schedule (e. g. , conference calls) Technical and administrative groups • Clear division of responsibility between locations 27 CS 501 Spring 2008
Meetings require leadership and a willingness to be led • Time keeping -- do not be late; end on time or earlier • Clear purpose for meeting, with agenda if needed e. g. , progress reports, design review, budget • Preparation materials circulated in advance with time to prepare studied by all participants • Facilitation during meeting opportunities for all to speak summing up to check agreement 28 • Notes taken during meeting (scribe) and circulated promptly CS 501 Spring 2008
Hiring Productivity is a combination of: • • 29 Analytic ability Verbal ability and communication skills Education Adaptability and inquisitiveness Personality and attitude Platform experience Programming language experience Application domain knowledge CS 501 Spring 2008
Staff Retention • • Feeling of appreciation management recognition money and promotion • Working conditions space, light, noise, parking flexibility • 30 Technically interesting work up to date hardware and software opportunities to learn and experiment Organizational dynamics CS 501 Spring 2008
Salaries Any software developer in the USA has plenty of money to live on (food, clothing, heat, etc. ). Salaries are used to satisfy the top levels of Maslow's Hierarchy: self-realization esteem The absolute level of salary is less important than its relative level and how it is presented: "The average raise is 3%, but you are getting 4%. " "Our salaries are in the top 25% of similar companies. " 31 CS 501 Spring 2008
Firmness Managers must be firm when needed: • Assignment of tasks must be equitable and open; everybody will have to tackle some of the dreary tasks • Carrots are better than sticks, but poor performance must be addressed. • Nobody is indispensable; nobody should be allowed to think that they are indispensable 32 CS 501 Spring 2008
Technical Challenges • Canceling projects Example: the Andrew window manager • Changes of environment Example: the World Wide Web • 33 Technical tinkering v. needed re-engineering CS 501 Spring 2008
Turning a Group Around To turn a weak group into a strong one is the greatest challenge of leadership • The art of the possible • Promotion of the best over the old leaders • Using opportunities to reorganize • Resignations and terminations • Respect people who try, yet refuse to accept problem areas Persistent and firm is better than brutal and abrupt 34 CS 501 Spring 2008
How to be Led As a junior member of a team, what can you do to make it productive? 35 CS 501 Spring 2008
To Build and Maintain a Strong Team Everybody has a different style. In my experience: • Be consistent in how you relate to people • Be open about problems and how you are addressing them • Explain your decisions • Do not have secrets • Ask for advice and help • Be constructive in criticism of people outside your team • Support and attend social events Set high standards! 36 CS 501 Spring 2008