info 420chapter 7 1 sw project management project schedule and budget info 420 glenn booker

INFO 420 Chapter 7 1

SW Project ManagementProject Schedule and Budget

INFO 420Glenn Booker

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Grand finale

Developing the project schedule and budget is the grand finale of the project planning process – our ultimate goalWe just defined the tasks and estimated their

duration (effort)Now identify the sequence of tasks,

interdependencies, and staffing needs

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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 includesCost estimating for tasks and their resourcesCost budgeting for the whole projectCost control – define processes

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Rolling up costs

Since our tasks were organized into phases and deliverables, we can roll up (summarize) costs to any level desiredCost per deliverableCost per phaseCost of the whole project

The sponsor needs to approve these costs

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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 activityGIGO applies here, not just to programming!

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Project schedule tools

Tools to show a project schedule includeGantt chartProject network diagram

Activity On the Node (AON) diagram Critical path analysis PERT charts Precedence diagramming method (PDM)

Critical chain project management (CCPM)

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Gantt chart

The Gantt chart is probably the most widely used project management toolTime 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

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Basic Gantt chart

IDTask Name

Start Finish DurationAug 2009

4 5 6 7 8 9 10 11 12 13 14 15 16 17

1 4d8/7/20098/4/2009Task 1

2 1d8/5/20098/5/2009Task 2

3 1d8/6/20098/6/2009Task 3

4 3d 4h8/12/20098/7/2009Task 4

5 0d8/12/20098/12/2009Task 5

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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 dateThis can help decide resource assignments

needed for critical tasks

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Activity On the Node

Activity On the Node (AON) diagrams represent the flow of tasks needed to complete the projectTasks are nodes (boxes)Arrows show the order in which they occur

The duration of tasks isn’t directly visible under AON, only time order


Activity On the Node

Tasks can be predecessors, successors, or in parallel Predecessor tasks must occur before another

taskSuccessor tasks must occur after another

taskParallel tasks may occur at the same time as

another task


Critical path analysis

Given an AON, critical path analysis determines which activities are directly connected to achieving the project scheduleThey are the critical path, which can change

Analytically, find the duration of each path through the AON diagram



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 delayedTasks 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



A manager might add resources to tasks on the critical path, if that will actually help finish them soonerThis technique can be called expediting or

crashing the project Fast tracking the project is done by

making tasks parallel that weren’t


PERT charts

PERT is the program evaluation and review technique, developed in the 50’sOften seen with CPM, or critical path method

A PERT chart also uses the AON graphic notation, but uses a different approach for estimation


Styles of PERT nodes

Early Start Duration Early Finish

Late Start Slack Late Finish

Task Name

Actual Start Actual Finish

Scheduled Finish

Scheduled Start

Task Name


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


Precedence diagramming method

The precedence diagramming method (PDM) adds to AON by showing the key sequence relationshipsFinish to start (most common, sequential)Start to startFinish to finishStart to finish


PDM node relationships

Task HTask G

Start-to-finish

Start-to-start

Task C

Task D

Finish-to-finish

Task E

Task F

Finish-to-start

Task A Task B

From Fig. 7.5


PDM

PDM can also show lead and lag times for activitiesLead time is an amount of time a task can

start before the end of its predecessorLag time is the amount of time a task must

start after the end of its predecessor Hence lag time = negative lead time


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


CCPM

CCPM takes that buffer from each task, and puts in in larger blocks where neededHow? Estimate tasks so that you only have

a 50% chance of completing them on timeThen take half of the difference in task time,

and put that into a buffer at the end of the project


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


PM software tools

There are several project management software tools for developing and managing schedulesMicrosoft Project is the de facto standardPlanner and OpenWorkBench are open

source tools Ok, so Project doesn’t have much

competition…


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


Project budget

The budget is straightforward to develop, once the schedule has been determinedDetermine 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


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.


Project budget

So if a software engineer averages $60k/year, their hourly rate is about $30/hrActually, 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


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 projectsLearning curve – might be covered by

prototypes


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?


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?


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!

info 420chapter 7 1 sw project management project schedule and budget info 420 glenn booker

Documents

project tasks

project duration

critical tasks

node tasks

project cost control

developing project schedule

visible tasks

sequence of tasks