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Information Systems Project Management IS Project Estimation. Miguel Nunes email: j.m.nunes@sheffield.ac.uk. Aims of this Session. To introduce estimation as an important project management activity; To discuss different types of estimation methods ;
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Information Systems Project ManagementIS Project Estimation Miguel Nunes email: j.m.nunes@sheffield.ac.uk
Aims of this Session To introduce estimation as an important project management activity; To discuss different types of estimation methods; To discuss different stages of the estimation process.
Information System Definition An Information System can be defined technically as a set of interrelated components that collect, process, store and retrieve, and distribute information to support decision making, co-ordination and control in an organisation. An information system is an organisational and management solution, based on information and communication technology, to a challenge posed by the environment.
Information SystemDefinition A system that assembles, stores, processes and delivers information relevant to an organisation (or socio-technical environment), in such a way that the information is accessible and useful to those who wish to use it as required by their activity practices, including managers, staff, customers, suppliers, other business partners and citizens. An IS is therefore an human-activity system which may or may not involve the use of IT based systems.
Types of IS Project Resources Any IS project has at least 4 stages: start-up; development; completion; operational.
Types of IS Project Resources A resource is any item or person required for the execution of the project (from clips to key technical personnel). In general resources can be categorised as follows: Labour (also known as Human Resources); Equipment; Materials; Space; Services; Time; Budgetary resources.
Types of IS Project Resources • Support: • Users; • Testers; • Project Champion; • Secretaries; • Clerks; • Training Officer: • Organising: • Steering Committee; • User Group; • Risk Management Committee; • Joint Application Development Team. • Management: • Project Manager; • Quality Manager; • Risk Manager; • Configuration and Integration Manager; • Technical: • Analysts and Designers; • Programmers; • Graphics Designer; • Database Administrator; • Implementation Officer; These team members may take one or more of the following types of roles: And more ……….
Types of IS Project Resources Human Resources is very expensive (typically 80% of budget of the project) and the more specialised the resources are the more scarce and expensive they become. Human resource allocation depends on: Management Style of Project Manager. Type and nature of the project; IS Methodology Selected; Constraints and Budget of the Project.
Types of IS Project Resources Time is a resource that is very scarce and limits the use of other resources. Time allocation in the plan depends on IS methodology, effort estimation, quality standards used, risk management and the use of human resources.
“ a coherent collection of concepts, beliefs, values and principles supported by resources to help a problem-solving group to perceive, generate, assess and carry-out in a non-random way changes to the information system” (Avison and Wood-Harper, 1990) 1. Set of methods for tackling the different problems involved. 2. Sound theoretical basis in order to understand why and when to use the methods. IS Development Methodologies
IS Development Methodologies A collection of procedures, techniques, tools and documentation aids that help developers in their efforts to understand users, their socio-technical environment, their work practices and their information needs. IS Methodologies consist of phases whish will guide the systems developers in what to do and their choice of techniques that might be appropriate at each stage. Each phase may contain subphases. These phases (or stages, or main activities) form the IS Project and help manage, control and evaluate the project.
IS Development Methodologies There are 3 main types of methodologies in use today: Structured Approaches (e.g. SSDAM) Agile Methodologies Prototyping approaches (e.g. RAD or DSDM) Incremental approaches (e.g. XP or SCRUM) Object Oriented Approaches (e.g. UML)
Information SystemsProject Planning Time allocation in the plan depends on the IS methodology selected, effort estimation, quality standards used, risk management and the use of human resources. Question answered: What IS Methodology to use? Who will do the work? Questions remaining: When will the work be done? How long will each of the stages, activities and tasks last? What type of quality do we need for our work and product? What risks are we willing to run?
Information SystemsProject Estimation Estimation implies that targets are set and that the project manager tries to meet those targets by allocating people and resources to tasks and activities and trying to anticipate how long each task my take to successfully achieve each of the targets.
Information SystemsProject Planning “It is very easy for estimators to be overly optimistic. At the beggining of a project, it is natural to assume that everything will work as planned. But, because the need to accomplish a wide variety of tasks – and their realtionships – projects rarely proceed as sheduled.” Why ?
Information SystemsProject Estimation Estimation is very difficult for IS project estimations because: IS projects are usually one-off affairs; IS estimates are usually prepared before a detailed specification of requirements is available (usually only after design stage, e.g. after TSO in SSADM); Programmers are often bad estimators, managers are often not technical enough in their thinking; Professionals in a team often have very different degrees of experience (what works for one may not work for others …); Very fast changing technologies make it sometimes difficult to use previous experience.
Estimates, but how? Estimates can be obtained by two means: Experience and Analogy; Mathematical formulae. Experience and Analogy tend to be the more important since it is able to draw upon the “real world events” in making predictions for the future. Mathematical formulae are used to quantify and manipulate past experience.
Estimating and Experience Estimating ( When and Who according to Planning What and How) Experience …. , experience … , experience.
Experience ... ? Traditionally, projects have been estimated by intuitive methods based on an individual’s previous “experience” often guesswork “guesstimate”multiplied by some “factor”to account for the unexpected.
Mathematical Approaches Lines of Codes (LOC); Function Points (FP); Object Points (OP). but can we use these ??? Usually garbage in gabage out processes based on guesstimate input.
Estimating Estimation must take account of broader project, organisational, economic and business considerations (holistic view). The accuracy of an estimate depends on: the quality of the data used to obtain it; the quality of the information available; the expertise of the estimator ... and a reasonable time scale to calculate the estimate.
Estimating ... But how then? The natural human problem solving method is to subdivide a problem until it is small enough to be understandable and manageable, and then hope to combine the solutions to answer the original problem.
Process-Based Estimation Process decomposition sets of: Stages into activities Activities into tasks. Consideration of past experience and data from past projects through: expert judgement; or analogy. Consideration of “especial factors” (individual skill, support tools, communication and co-ordination problems); Estimation of effort required for each individual task.
Process-Based Estimation That is why. Why ? Usually a top-down approach: Starting from an understanding of the whole project and then broken down into the component stages, activities and task.
Process-Based Estimation But … the final project estimate is calculated bottom-up: Once component tasks are identified, understood and sized these individual tasks are identified and aggregated to determine activity estimates, which in turn are aggregated to determine stage estimate, which in turn are aggregated to determine an estimate for the whole project.
Process-Based Estimation Detailed Task Lists (DTL) A detailed task list (DTL) is a listing of unique work packages (tasks, activities and stages) drawn form applying a particular IS methdology to a specific project, including clear description of: Work to be done; Assignment of responsibilities; Predecessor relationships.
Process-Based Estimation Work Breakdown Structure (WBS) The Work Breakdown Structure (WBS) are top-down herarchical charts of phases, activities, tasks and sub-tasks required to complete the project. These charts are build from the DTLs by adopting the 4 basic stages of an IS project: start-up; development; completion and operational. Therefore, the elements of a WBS are discrete work packages that can be separately estimated, planned and budgeted (Cantor, 1998).
Process-Based Estimation WBS example
Process-Based Estimation WBS representation? Hierarchical trees ... An then use in ... CPM diagrams; Gantt charts.
Process-Based Estimation So will we be secure with process based estimation? “It is very easy for estimators to be overly optimistic. At the beggining of a project, it is natural to assume that everything wll work as planned. But because the need to accomplish a wide variety of tasks – and their realtionships – projects rarely proceed as sheduled.” Still? ... Why ?
This module’s question: “We know why projects fail, we know how to prevent their failure -- so why do they still fail?“Cobb (1995) Old question!???
Project Management What has happened ? What is happening ? What is going to happen ? What needs to be done ? How are we going to do it ? When are we doing it ? Who is going to do it ? What is the quality of our work (product) ? What are the risks involved ?
Project Management Planning and Organising (What and How) Estimating ( When and Who) Scheduling and Monitoring ( awareness of progression, remediation action, quality assurance)
Planning and Organising Planning and Organising (What and How) Understanding requirements; Selecting a methodology; Estimating Effort; Determining deliverables and milestones; Determining verification and validation checks.
To Sum up ... However, estimation is an ongoing activity that starts at the initial proposal stage and continues throughout the lifetime of a project and requires good communication in the team. It is not THE whole answer to our question. Allocation of time and human resources should be is based on Process Based Estimation ... supported by DTL and WBS and expressed in terms of Gantt and CPM charts.
To Sum up ... If Time allocation in the plan depends on IS methodology, effort estimation, quality standards used, risk management and the use of human resources. Thenwe still have two questions to answer.
Your Turn now !!!! Group 1 - UML Group 2 - XP Group 3 - RAD Group 4 - SSADM To Sum up ... For Tomorrow: Prepare the structure of your project by identifying ALL the phases, activities and tasks of that your methodology needs for the specific IS Projectin the case studyand express it in terms of a DTL, a WBS and a Gant Chart.