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SW Project Management Project Schedule and Budget. INFO 420 Glenn Booker. Grand finale. Developing the project schedule and budget is the grand finale of the project planning process – our ultimate goal We just defined the tasks and estimated their duration (effort)
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SW Project ManagementProject Schedule and Budget INFO 420 Glenn Booker Chapter 7
Grand finale • Developing the project schedule and budget is the grand finale of the project planning process – our ultimate goal • We just defined the tasks and estimated their duration (effort) • Now identify the sequence of tasks, interdependencies, and staffing needs Chapter 7
Project cost management • The budget is determined from the project schedule, the cost assigned to tasks, and other indirect costs or resources • Project cost management includes • Cost estimating for tasks and their resources • Cost budgeting for the whole project • Cost control – define processes Chapter 7
Rolling up costs • Since our tasks were organized into phases and deliverables, we can roll up (summarize) costs to any level desired • Cost per deliverable • Cost per phase • Cost of the whole project • The sponsor needs to approve these costs Chapter 7
Developing project schedule • A key sanity check is that each of the estimates for each task is really reasonable according to the experts in that activity • GIGO applies here, not just to programming! Chapter 7
Project schedule tools • Tools to show a project schedule include • Gantt chart • Project network diagram • Activity On the Node (AON) diagram • Critical path analysis • PERT charts • Precedence diagramming method (PDM) • Critical chain project management (CCPM) Chapter 7
Gantt chart • The Gantt chart is probably the most widely used project management tool • Time is the X axis, from days to years • The current date is readily visible • Tasks are on the Y axis • Bars represent WBS tasks • Milestones are diamond shapes • An inset bar can show actual work progress Chapter 7
Basic Gantt chart Chapter 7
Project network diagram • Project network diagrams are also based on the WBS, but also show more info on task sequence or dependencies • Many also show when tasks must start or stop in order not to affect project completion date • This can help decide resource assignments needed for critical tasks Chapter 7
Activity On the Node • Activity On the Node (AON) diagrams represent the flow of tasks needed to complete the project • Tasks are nodes (boxes) • Arrows show the order in which they occur • The duration of tasks isn’t directly visible under AON, only time order Chapter 7
Activity On the Node • Tasks can be predecessors, successors, or in parallel • Predecessor tasks must occur before another task • Successor tasks must occur after another task • Parallel tasks may occur at the same time as another task Chapter 7
Critical path analysis • Given an AON, critical path analysis determines which activities are directly connected to achieving the project schedule • They are the critical path, which can change • Analytically, find the duration of each path through the AON diagram Chapter 7
Critical path analysis • The path with the longest duration is the critical path (and the project duration) • If any tasks on the critical path are delayed, the overall project completion will be delayed • Tasks not on the critical path may have a non-zero amount of slack or float, which is the amount of duration they can slip without affecting the project Chapter 7
Critical path analysis • A manager might add resources to tasks on the critical path, if that will actually help finish them sooner • This technique can be called expediting or crashing the project • Fast tracking the project is done by making tasks parallel that weren’t Chapter 7
PERT charts • PERT is the program evaluation and review technique, developed in the 50’s • Often seen with CPM, or critical path method • A PERT chart also uses the AON graphic notation, but uses a different approach for estimation Chapter 7
Styles of PERT nodes Chapter 7
PERT charts • For each task, estimate the lowest (optimistic), most likely, and highest (pessimistic) durations, then use • estimate = (low + high + 4*likely)/6 • The critical path analysis can be done based on these estimates Chapter 7
Precedence diagramming method • The precedence diagramming method (PDM) adds to AON by showing the key sequence relationships • Finish to start (most common, sequential) • Start to start • Finish to finish • Start to finish Chapter 7
PDM node relationships From Fig. 7.5 Chapter 7
PDM • PDM can also show lead and lag times for activities • Lead time is an amount of time a task can start before the end of its predecessor • Lag time is the amount of time a task must start after the end of its predecessor • Hence lag time = negative lead time Chapter 7
Critical chain project management • Critical chain project management (CCPM) is a newcomer (Goldratt, 1997) • It assumes that all estimates are inflated • We still finish projects late because • We wait until the last minute (student syndrome) • Projects fill the time available (Parkinson’s law) • Resource contention Chapter 7
CCPM • CCPM takes that buffer from each task, and puts in in larger blocks where needed • How? Estimate tasks so that you only have a 50% chance of completing them on time • Then take half of the difference in task time, and put that into a buffer at the end of the project Chapter 7
CCPM • Yes, you have to estimate each task twice • Once normally, and once for 50% chance completion • CCPM also accounts for resource limits, by identifying the resources for each task and buffers for each type of resource Chapter 7
PM software tools • There are several project management software tools for developing and managing schedules • Microsoft Project is the de facto standard • Planner and OpenWorkBench are open source tools • Ok, so Project doesn’t have much competition… Chapter 7
PM software tools • Often projects are planned in detail only a few months in the future, a rolling wave approach • There’s an outline of the rest of the project, particularly for planning long lead time items Chapter 7
Project budget • The budget is straightforward to develop, once the schedule has been determined • Determine the type of resource(s) needed for each task, and how many of them are needed for its duration (0.1, 2.5, whatever) • Find the cost of each resource type ($/hr), and multiply that by how many and the duration = cost per task Chapter 7
Project budget • Check for overuse of resources – often not recommended to use 155% of a person’s time • To find the cost of each resource*, assess their typical annual salary**, divide by 2000 (hours per work year), and multiply by 2.5 (to account for overhead expenses) * This is a heuristic. ** You could look for salary surveys. Chapter 7
Project budget • So if a software engineer averages $60k/year, their hourly rate is about $30/hr • Actually, a normal work year is 40*52 = 2080 hours, but we’re just getting a rough estimate • Multiply by 2.5 to get a labor rate of $75/hr • This is the ‘true cost’ in the text Chapter 7
Other costs • Labor is the biggest cost on most projects, but other costs should be considered • Indirect costs – are admin assistants, facilities, insurance, etc. paid by the project, or from overhead? • Sunk costs – from previous bad projects • Learning curve – might be covered by prototypes Chapter 7
Other costs • Reserves – most projects keep back a 10-15% reserve from the total actual budget, in anticipation of some cost overruns • Project-specific hardware and software – plan for infrastructure costs (servers, network equipment, software) which aren’t part of normal office & facility environment • Travel, e.g. to the customer? Chapter 7
Resource allocation • Again, make sure that individuals aren’t scheduled for over 100% of their time • Also consider resource leveling • Are there times when people are needed, then not, then needed again? • What will those people do in the middle? Chapter 7
Baseline plan • Once all these issues have been identified and agreed upon, you have the baseline project schedule, which feeds the project plan • All measurements of ‘planned versus actuals’ hinge upon this plan! Chapter 7