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Project Time Management Information Technology Project Management, Fifth Edition Project Time Management Information Technology Project Management, Fifth Edition

Project Time Management “The processes required to accomplish timely completion of the project” Project Time Management “The processes required to accomplish timely completion of the project”

Why Time Management? Part of triple constraint, can’t manage one without the others (scope, Why Time Management? Part of triple constraint, can’t manage one without the others (scope, time, and quality) Second hardest section on the test behind integration

How Do We Manage Time? Six processes Define Activities Sequence Activities Estimate Activity Resources How Do We Manage Time? Six processes Define Activities Sequence Activities Estimate Activity Resources Estimate Activity Durations Develop Schedule Control Schedule

Importance of Project Schedules Managers often cite delivering projects on time as one of Importance of Project Schedules Managers often cite delivering projects on time as one of their biggest challenges Time has the least amount of flexibility; it passes no matter what happens on a project Schedule issues are the main reason for conflicts on projects, especially during the second half of projects 5 Project Time Management

Project Time Management Processes Activity definition: identifying the specific activities/tasks that the project team Project Time Management Processes Activity definition: identifying the specific activities/tasks that the project team members and stakeholders must perform to produce the project deliverables Activity sequencing: identifying and documenting the relationships between project activities Activity resource estimating: estimating how many resources a project team should use to perform project activities Activity duration estimating: estimating the number of work periods that are needed to complete individual activities Schedule development: analyzing activity sequences, activity resource estimates, and activity duration estimates to create the project schedule Schedule control: controlling and managing changes to the project schedule 6 Project Time Management

Project Time Management Summary 7 Project Time Management Project Time Management Summary 7 Project Time Management

Activity Definition Project schedules grow out of the basic documents that initiate a project Activity Definition Project schedules grow out of the basic documents that initiate a project Project charter includes start and end dates and budget information Scope statement and WBS help define what will be done Activity definition involves developing a more detailed WBS and supporting explanations to understand all the work to be done so you can develop realistic cost and duration estimates 8 Project Time Management

Activity Definition The basis for creating a project schedule is derived from four project Activity Definition The basis for creating a project schedule is derived from four project time management processes Activity definition – further defining the scope Activity sequencing – further defining the time Activity resource and activity duration (further defining the time and cost) 9 Project Time Management

Activity Lists and Attributes An activity list is a tabulation of activities to be Activity Lists and Attributes An activity list is a tabulation of activities to be included on a project schedule that includes: The activity name An activity identifier or number A brief description of the activity Activity attributes provide more information such as predecessors, successors, logical relationships, leads and lags, resource requirements, constraints, imposed dates, and assumptions related to the activity 10 Project Time Management

Milestones A milestone is a significant event that normally has no duration Not every Milestones A milestone is a significant event that normally has no duration Not every deliverable or output created for a project is a milestone It often takes several activities and a lot of work to complete a milestone They’re useful tools for setting schedule goals and monitoring progress Examples include obtaining customer sign-off on key documents or completion of specific products such as software modules or the installation of new hardware 11 Project Time Management

Activity Sequencing After defining project activities, the next step is activity sequencing Involves reviewing Activity Sequencing After defining project activities, the next step is activity sequencing Involves reviewing the activity list and attributes, project scope statement, milestone list and approved change requests to determine the relationships between activities A dependency or relationship is the sequencing of project activities or tasks You must determine dependencies in order to use critical path analysis 12 Project Time Management

Three Types of Dependencies Mandatory dependencies: inherent in the nature of the work being Three Types of Dependencies Mandatory dependencies: inherent in the nature of the work being performed on a project, sometimes referred to as hard logic Discretionary dependencies: defined by the project team; sometimes referred to as soft logic and should be used with care since they may limit later scheduling options Don’t start detailed design work until users sign-off on all the analysis – good practice but can delay project External dependencies: involve relationships between project and non-project activities Delivery of new hardware; if delayed can impact project schedule 13 Project Time Management

Network Diagrams Network diagrams are the preferred technique for showing activity sequencing A network Network Diagrams Network diagrams are the preferred technique for showing activity sequencing A network diagram is a schematic display of the logical relationships among, or sequencing of, project activities Two main formats are Activity on arrow (AOA) diagramming technique Activity on Node (AON) diagramming technique (Precedence diagramming methods – PDM) 14 Project Time Management

Arrow Diagramming Method (ADM) Commonly called Activity on Arrow (AOA) Boxes are used to Arrow Diagramming Method (ADM) Commonly called Activity on Arrow (AOA) Boxes are used to represent dependencies with arrows used for tasks Only Finish to Start relationships Can use “dummy” activities Used for CPM and PERT estimating methods Activity A Task Dependency

Sample Activity-on-Arrow (AOA) Network Diagram for Project X 17 Project Time Management Sample Activity-on-Arrow (AOA) Network Diagram for Project X 17 Project Time Management

Arrow Diagramming Method (ADM) Also called activity-on-arrow (AOA) network diagrams Activities are represented by Arrow Diagramming Method (ADM) Also called activity-on-arrow (AOA) network diagrams Activities are represented by arrows Nodes or circles are the starting and ending points of activities Can only show finish-to-start dependencies Can omit activities that have no dependencies 18 Project Time Management

Process for Creating AOA Diagrams 1. Find all of the activities that start at Process for Creating AOA Diagrams 1. Find all of the activities that start at node 1: Draw their finish nodes and draw arrows between node 1 and those finish nodes; put the activity letter or name and duration estimate on the associated arrow 2. Continue drawing the network diagram, working from left to right: Look for bursts and merges Bursts occur when a single node is followed by two or more activities A merge occurs when two or more nodes precede a single node 19 3. Continue drawing the project network diagram until all activities are included on the diagram that have dependencies 4. As a rule of thumb, all arrowheads should face toward the right, and no arrows should cross on an AOA network diagram Project Time Management

Precedence Diagramming Method (PDM) More popular than ADM method and used by project management Precedence Diagramming Method (PDM) More popular than ADM method and used by project management software Activities are represented by boxes Arrows show relationships between activities Better at showing different types of dependencies 20 Project Time Management

ACTIVITY-ON-NODE (AON) OR PRECEDENCE DIAGRAMMING METHOD (PDM) Commonly called Activity on Node (AON), most ACTIVITY-ON-NODE (AON) OR PRECEDENCE DIAGRAMMING METHOD (PDM) Commonly called Activity on Node (AON), most commonly used sequencing method Boxes are used to represent tasks with arrows used for dependencies Four types of dependencies Finish to Start – Task must finish before next one can start Finish to Finish – One task must finish before the other can finish Start to Start – One task must start before the other can start Start to Finish – One task must start before the other can finish Activity A Activity B Dependency Node

Task Dependency Types 22 Project Time Management Task Dependency Types 22 Project Time Management

Sample PDM Network Diagram 23 Project Time Management Sample PDM Network Diagram 23 Project Time Management

Method Comparison PDM (AON) Method Start Build Foundation Build Walls Build Roof Finis h Method Comparison PDM (AON) Method Start Build Foundation Build Walls Build Roof Finis h Install Grass ADM (AOA) Method Build Foundation Start Build Walls Build Roof Install Grass Finis h

Activity Resource Estimating Before estimating activity durations, you must have a good idea of Activity Resource Estimating Before estimating activity durations, you must have a good idea of the quantity and type of resources that will be assigned to each activity Consider important issues in estimating resources How difficult will it be to do specific activities on this project? What is the organization’s history in doing similar activities? Are the required resources available or need to be acquired? A resource breakdown structure is a hierarchical structure that identifies the project’s resources by category and type 25 Project Time Management

Activity Duration Estimating Duration includes the actual amount of time worked on an activity Activity Duration Estimating Duration includes the actual amount of time worked on an activity plus elapsed time Effort is the number of workdays or work hours required to complete a task Effort does not normally equal duration People doing the work should help create estimates, and an expert should review them 26 Project Time Management

Estimating Methods CPM (Critical Path Method) One time estimate per task Controls cost with Estimating Methods CPM (Critical Path Method) One time estimate per task Controls cost with flexible schedule Only on AOA networks (can have dummies) Not the same thing as schedule critical path PERT (Program Evaluation and Review Technique) Three estimates per activity (Optimistic, Pessimistic, most likely) Emphasis on meeting schedule with flexible cost Only on AOA networks (can have dummies) Monte Carlo Simulation Gives probabilities of completing project on time, cost, and whether or not project is on critical path

CPM (Critical Path Method) You should remember that this method: Has one time estimate CPM (Critical Path Method) You should remember that this method: Has one time estimate per task Has an emphasis on controlling cost and leaving the schedule flexible Can be drawn only on an activity-on-arrow (AOA) diagram Can have dummies ESTIMATING USING CPM When estimating using a one-time estimate (CPM), one estimate per task is received. For example, the person doing the estimating in effect says that the task will take exactly five weeks. This method uses only a most likely time estimate. 28 • GU, PMP Preparatory Course, MODULE 5

Three-Point Estimates Instead of providing activity estimates as a discrete number, such as four Three-Point Estimates Instead of providing activity estimates as a discrete number, such as four weeks, it’s often helpful to create a three-point estimate An estimate that includes an optimistic, most likely, and pessimistic estimate, such as three weeks for the optimistic, four weeks for the most likely, and five weeks for the pessimistic estimate Three-point estimates are needed for PERT and Monte Carlo simulations 29 Project Time Management

PERT (Program Evaluation and Review Technique) page 75 You should remember that this method: PERT (Program Evaluation and Review Technique) page 75 You should remember that this method: Has three estimates per activity Optimistic Pessimistic Most likely Can be used to estimate time or cost Has an emphasis on meeting schedules with flexibility on costs Can be drawn only on an activity-on-arrow (AOA) diagram Can have dummies 30 GU, PMP Preparatory Course, MODULE 5

Estimating with PERT Formula (Expected Duration) =(P+4 M+O)/6 Standard Deviation = (P-O)/6 Variance = Estimating with PERT Formula (Expected Duration) =(P+4 M+O)/6 Standard Deviation = (P-O)/6 Variance = [(P-O)/6]2 Task O P PERT Optimistic A M Most Likely Pessimistic (Expected Duration) 2 days 4 days 8 days 4. 3 days Std Dev Variance 1 day

Exercise Complete the chart using the previous formulas. All estimates are in hours. 32 Exercise Complete the chart using the previous formulas. All estimates are in hours. 32 • GU, PMP Preparatory Course, MODULE 5

MONTE CARLO SIMULATION (page 44, 75 and 139 titled simulation) The simulation can tell MONTE CARLO SIMULATION (page 44, 75 and 139 titled simulation) The simulation can tell you: The probability of completing the project on any specific day The probability of completing the project for any specific amount of cost The probability of any task actually being on the critical path The overall project risk 33 • GU, PMP Preparatory Course, MODULE 5

Schedule Development Uses results of the other time management processes to determine the start Schedule Development Uses results of the other time management processes to determine the start and end date of the project Ultimate goal is to create a realistic project schedule that provides a basis for monitoring project progress for the time dimension of the project Important tools and techniques include Gantt charts, critical path analysis, critical chain scheduling, and PERT analysis 34 Project Time Management

Gantt Charts Gantt charts provide a standard format for displaying project schedule information by Gantt Charts Gantt charts provide a standard format for displaying project schedule information by listing project activities and their corresponding start and finish dates in a calendar format Symbols include: Black diamonds: milestones Thick black bars: summary tasks Lighter horizontal bars: durations of tasks Arrows: dependencies between tasks 35 Project Time Management

Figure 6 -5: Gantt Chart for Project X Note: Darker bars would be red Figure 6 -5: Gantt Chart for Project X Note: Darker bars would be red in Project 2007 to represent critical tasks 36 Project Time Management

Gantt Chart for Software Launch Project 37 Project Time Management Gantt Chart for Software Launch Project 37 Project Time Management

Adding Milestones to Gantt Charts Many people like to focus on meeting milestones, especially Adding Milestones to Gantt Charts Many people like to focus on meeting milestones, especially for large projects Milestones emphasize important events or accomplishments on projects Normally create milestone by entering tasks with a zero duration, or you can mark any task as a milestone 38 Project Time Management

SMART Criteria Milestones should be: Specific Measurable Assignable Realistic Time-framed 39 Project Time Management SMART Criteria Milestones should be: Specific Measurable Assignable Realistic Time-framed 39 Project Time Management

Best Practice The five key points of using project milestones include the following: 1. Best Practice The five key points of using project milestones include the following: 1. Define milestones early in the project and include them in the Gantt chart to provide a visual guide 2. Keep milestones small and frequent 3. The set of milestones must be all-encompassing 4. Each milestone must be binary, meaning it is either complete or incomplete 5. Carefully monitor the critical path 40 Project Time Management

Sample Tracking Gantt Chart 41 Project Time Management Sample Tracking Gantt Chart 41 Project Time Management

Critical Path Method (CPM) CPM is a network diagramming technique used to predict total Critical Path Method (CPM) CPM is a network diagramming technique used to predict total project duration A critical path for a project is the series of activities that determines the earliest time by which the project can be completed The critical path is the longest path through the network diagram and has the least amount of slack or float Slack or float is the amount of time an activity may be delayed without delaying a succeeding activity or the project finish date 42 Project Time Management

Calculating the Critical Path First develop a good network diagram Add the duration estimates Calculating the Critical Path First develop a good network diagram Add the duration estimates for all activities on each path through the network diagram The longest path is the critical path If one or more of the activities on the critical path takes longer than planned, the whole project schedule will slip unless the project manager takes corrective action 43 Project Time Management

Determining the Critical Path for Project X 44 Project Time Management Determining the Critical Path for Project X 44 Project Time Management

More on the Critical Path A project team at Apple computer put a stuffed More on the Critical Path A project team at Apple computer put a stuffed gorilla on the top of the cubicle of the person currently managing a critical task The critical path is not the one with all the critical activities; it only accounts for time Remember the example of growing grass being on the critical path for Disney’s Animal Kingdom There can be more than one critical path if the lengths of two or more paths are the same The critical path can change as the project progresses 45 Project Time Management

Using Critical Path Analysis to Make Schedule Trade-offs Free slack or free float is Using Critical Path Analysis to Make Schedule Trade-offs Free slack or free float is the amount of time an activity can be delayed without delaying the early start of any immediately following activities Total slack or total float is the amount of time an activity may be delayed from its early start without delaying the planned project finish date A forward pass through the network diagram determines the early start and finish dates A backward pass determines the late start and finish dates 46 Project Time Management

Scheduling from Estimates Critical Path Longest time through the network diagram, the shortest time Scheduling from Estimates Critical Path Longest time through the network diagram, the shortest time the project is expected to take Slack (or Float) The amount of time a task can be delayed without impacting the project Calculated using: Late Start – Early Start (LS-ES) Or Late Finish – Early Finish (LF-EF) Early Starts computed by making a “forward pass” through the network while late starts are computed using a “backward pass”

Free and Total Float or Slack for Project X 48 Project Time Management Free and Total Float or Slack for Project X 48 Project Time Management

How to Find the Critical Path 1. 2. 3. 4. To find the critical How to Find the Critical Path 1. 2. 3. 4. To find the critical path, need to determine the following quantities for each activity in the network Earliest start time (ES): the earliest time an activity can begin ES without violation of immediate predecessor requirements Earliest finish time (EF): the earliest time at which an activity can end EF Latest start time (LS): the latest time an activity can begin without LS delaying the entire project Latest finish time (LF): the latest time an activity can end without LF delaying the entire project

How to Find the Critical Path In the nodes, the activity time and the How to Find the Critical Path In the nodes, the activity time and the early and late start and finish times are represented in the following manner ACTIVITY ES LS t EF LF Earliest times are computed as Earliest finish time = Earliest start time + Expected activity time EF = ES + t Earliest start = Largest of the earliest finish times of immediate predecessors ES = Largest EF of immediate predecessors

How to Find the Critical Path At the start of the project we set How to Find the Critical Path At the start of the project we set the time to zero Thus ES = 0 for both A and B A ES = 0 t=2 EF = 0 + 2 = 2 B ES = 0 t=3 EF = 0 + 3 = 3 Start

How to Find the Critical Path General Foundry’s ES and EF times A 0 How to Find the Critical Path General Foundry’s ES and EF times A 0 2 2 C 2 2 4 F 4 E 4 Start B 0 Figure 13. 4 3 3 D 3 4 7 3 7 4 8 H 13 G 8 5 13 2 15 Finish

How to Find the Critical Path Latest times are computed as Latest start time How to Find the Critical Path Latest times are computed as Latest start time = Latest finish time – Expected activity time LS = LF – t Latest finish time = Smallest of latest start times for following activities LF = Smallest LS of following activities For activity H LS = LF – t = 15 – 2 = 13 weeks

How to Find the Critical Path General Foundry’s LS and LF times A 0 How to Find the Critical Path General Foundry’s LS and LF times A 0 0 2 2 2 C 2 2 2 4 4 F 4 10 E 4 4 Start B 0 1 Figure 13. 5 3 3 4 D 3 4 4 7 8 3 7 13 4 8 8 H 13 13 G 8 8 5 13 13 2 15 15 Finish

How to Find the Critical Path Once ES, LS, EF, and LF have been How to Find the Critical Path Once ES, LS, EF, and LF have been determined, it is a simple matter to find the amount of slack time that each activity has Slack = LS – ES, or Slack = LF – EF From Table 13. 3 we see activities A, C, E, G, and H have no slack time These are called critical activities and they are said to be on the critical path The total project completion time is 15 weeks Industrial managers call this a boundary timetable

How to Find the Critical Path General Foundry’s schedule and slack times ACTIVITY EARLIEST How to Find the Critical Path General Foundry’s schedule and slack times ACTIVITY EARLIEST START, ES EARLIEST FINISH, EF LATEST START, LS LATEST FINISH, LF SLACK, LS – ES ON CRITICAL PATH? A 0 2 0 Yes B 0 3 1 4 1 No C 2 4 0 Yes D 3 7 4 8 1 No E 4 8 0 Yes F 4 7 10 13 6 No G 8 13 0 Yes H 13 15 0 Yes Table 13. 3

How to Find the Critical Path General Foundry’s critical path A 0 0 2 How to Find the Critical Path General Foundry’s critical path A 0 0 2 2 2 C 2 2 2 4 4 F 4 10 E 4 4 Start B 0 1 Figure 13. 6 3 3 4 D 3 4 4 7 8 3 7 13 4 8 8 H 13 13 G 8 8 5 13 13 2 15 15 Finish

Using the Critical Path to Shorten a Project Schedule Three main techniques for shortening Using the Critical Path to Shorten a Project Schedule Three main techniques for shortening schedules Shortening durations of critical activities/tasks by adding more resources or changing their scope Crashing activities by obtaining the greatest amount of schedule compression for the least incremental cost A 2 week task with one person working 50% could be shortened to 1 week if the person is assigned 100% no increase in cost Or, a temporary worker could be hired to work in parallel with the other worker to speed up the task (at a cost) 58

Project Crashing Projects will sometimes have deadlines that are impossible to meet using normal Project Crashing Projects will sometimes have deadlines that are impossible to meet using normal procedures By using exceptional methods it may be possible to finish the project in less time than normally required However, this usually increases the cost of the project Reducing a project’s completion time is called crashing

Project Crashing a project starts with using the normal time to create the critical Project Crashing a project starts with using the normal time to create the critical path The normal cost is the cost for completing the activity using normal procedures If the project will not meet the required deadline, extraordinary measures must be taken The crash time is the shortest possible activity time and will require additional resources The crash cost is the price of completing the activity in the earlier-than-normal time

Four Steps to Project Crashing 1. Find the normal critical path and identify the Four Steps to Project Crashing 1. Find the normal critical path and identify the critical activities 2. Compute the crash cost per week (or other time period) for all activities in the network using the formula Crash cost – Normal cost Crash cost/Time period = Normal time – Crash time

Four Steps to Project Crashing 3. 4. Select the activity on the critical path Four Steps to Project Crashing 3. 4. Select the activity on the critical path with the smallest crash cost per week and crash this activity to the maximum extent possible or to the point at which your desired deadline has been reached Check to be sure that the critical path you were crashing is still critical. If the critical path is still the longest path through the network, return to step 3. If not, find the new critical path and return to step 2.

General Foundry Example General Foundry has been given 14 weeks instead of 16 weeks General Foundry Example General Foundry has been given 14 weeks instead of 16 weeks to install the new equipment The critical path for the project is 15 weeks What options do they have? The normal and crash times and costs are shown in Table 13. 9 Crash costs are assumed to be linear and Figure 13. 11 shows the crash cost for activity B Crashing activity A will shorten the completion time to 14 but it creates a second critical path B, D, G, H because when you recalculate the LF and LS times for B and D they now match the EF and ES Any further crashing must be done to both critical paths

General Foundry Example Normal and crash data for General Foundry TIME (WEEKS) COST ($) General Foundry Example Normal and crash data for General Foundry TIME (WEEKS) COST ($) ACTIVITY NORMAL CRASH COST PER WEEK ($) CRITICAL PATH? A 2 1 22, 000 23, 000 1, 000 Yes B 3 1 30, 000 34, 000 2, 000 No C 2 1 26, 000 27, 000 1, 000 Yes D 4 3 48, 000 49, 000 1, 000 No E 4 2 56, 000 58, 000 1, 000 Yes F 3 2 30, 000 30, 500 No G 5 2 80, 000 86, 000 2, 000 Yes H 2 1 16, 000 19, 000 3, 000 Yes Table 13. 9

General Foundry Example Crash and normal times and costs for activity B Activity Cost General Foundry Example Crash and normal times and costs for activity B Activity Cost Crash Cost/Week = $34, 000 – Crash Cost – Normal Cost Normal Time – Crash Time $34, 000 – $30, 000 3– 1 $4, 000 = = $2, 000/Week 2 Weeks $33, 000 – = $32, 000 – $31, 000 – Normal $30, 000 – Normal Cost – | 0 Figure 13. 11 | 1 Crash Time | 2 | 3 Normal Time (Weeks)

Using the Critical Path to Shorten a Project Schedule Fast tracking activities by doing Using the Critical Path to Shorten a Project Schedule Fast tracking activities by doing them in parallel or overlapping them instead of doing them in sequence Instead of waiting for all analysis to be completed before starting coding, some coding could begin for those tasks that have been fully analyzed Drawback – starting a task too soon could lengthen the project because other tasks whose analysis has not been completed could impact this task and cause rework 66 Project Time Management

Importance of Updating Critical Path Data It is important to update project schedule information Importance of Updating Critical Path Data It is important to update project schedule information to meet time goals for a project The critical path may change as you enter actual start and finish dates If you know the project completion date will slip, be proactive and negotiate with the project sponsor and stakeholders 67 Project Time Management

Program Evaluation and Review Technique (PERT) PERT is a network analysis technique used to Program Evaluation and Review Technique (PERT) PERT is a network analysis technique used to estimate project duration when there is a high degree of uncertainty about the individual activity duration estimates PERT uses probabilistic time estimates Duration estimates based on using optimistic, most likely, and pessimistic estimates of activity durations, or a three-point estimate PERT attempts to address the risk associated with duration estimates by developing schedules that are more realistic It involves more work than CPM since it requires several duration estimates 68 Project Time Management

PERT Formula and Example PERT weighted average = optimistic time + 4 X most PERT Formula and Example PERT weighted average = optimistic time + 4 X most likely time + pessimistic time 6 Example: PERT weighted average = 8 workdays + 4 X 10 workdays + 24 workdays = 12 days 6 where optimistic time= 8 days, most likely time = 10 days, and pessimistic time = 24 days Therefore, you’d use 12 days on the network diagram instead of 10 when using PERT for the above example 69 Project Time Management

Schedule Control Perform reality checks on schedules Allow for contingencies Don’t plan for everyone Schedule Control Perform reality checks on schedules Allow for contingencies Don’t plan for everyone to work at 100% capacity all the time Hold progress meetings with stakeholders and be clear and honest in communicating schedule issues 70 Project Time Management

Working with People Issues Strong leadership helps projects succeed more than good PERT charts Working with People Issues Strong leadership helps projects succeed more than good PERT charts Project managers should use: Empowerment Incentives Discipline Negotiation 71 Project Time Management

Using Software to Assist in Time Management Software for facilitating communications helps people exchange Using Software to Assist in Time Management Software for facilitating communications helps people exchange schedule-related information Decision support models help analyze trade-offs that can be made Project management software can help in various time management areas 72 Project Time Management

Words of Caution on Using Project Management Software Many people misuse project management software Words of Caution on Using Project Management Software Many people misuse project management software because they don’t understand important concepts and have not had training You must enter dependencies to have dates adjust automatically and to determine the critical path You must enter actual schedule information to compare planned and actual progress 73 Project Time Management

What is a critical path and how does it help the project manager? The What is a critical path and how does it help the project manager? The critical path is the longest duration path through a network diagram It determines the shortest time to complete the project. HINT: The easiest way to find the critical path is to add the lengths of time for each path in a network diagram. The path with the longest duration is the critical path. 74 GU, PMP Preparatory Course, MODULE 5

Definitions LAG: (page 74) Inserted waiting time between tasks. For example, you must wait Definitions LAG: (page 74) Inserted waiting time between tasks. For example, you must wait three days after pouring concrete before you can construct the frame for a house. SLACK (FLOAT): The amount of time a task can be delayed without delaying the project. Tasks on the critical path almost always have zero slack. Critical path tasks that are delayed or have dictated dates can result in negative slack. 75 GU, PMP Preparatory Course, MODULE 5

Slack Subcategories Free Slack (float) the amount of time a task can be delayed Slack Subcategories Free Slack (float) the amount of time a task can be delayed without delaying the early start date of its successor Total Slack (float) the amount of time a task can be delayed without delaying the project completion date Project slack (float) the amount of time a project can be delayed without delaying the externally imposed project completion date required by the customer or management, or previously committed to by the project manager 76 GU, PMP Preparatory Course, MODULE 5

Exercise 1 Test yourself by answering the questions below. You are the project manager Exercise 1 Test yourself by answering the questions below. You are the project manager for a new project and have figured out the following dependencies. Task 1 can start immediately and has an estimated duration of 3 weeks. Task 2 can start after task 1 is completed and has an estimated duration of 3 weeks. Task 3 can start after task 1 is completed and has an estimated duration of 6 weeks. Task 4 can start after task 2 is completed and has an estimated duration of 8 weeks. 77 GU, PMP Preparatory Course, MODULE 5

Exercise 1 (Continued) Task 5 can start after task 4 is completed and after Exercise 1 (Continued) Task 5 can start after task 4 is completed and after task 3 is completed. This task takes 4 weeks. 1. What is the duration of the critical path? ___________ 2. What is the slack of task 3? ________________ 3. What is the slack of task 2? 4. What is the slack of the path with the longest slack? 78 GU, PMP Preparatory Course, MODULE 5

Exercise 1 (Continued) 5. The resource working on task 3 is replaced with another Exercise 1 (Continued) 5. The resource working on task 3 is replaced with another resource that is less experienced. The task will now take 10 weeks. How will this affect the project? 6. Using the original information, after some arguing between stakeholders, a new task 6 is added to the project. It will take eleven weeks to complete and must be completed before task 5 and after task 3. Management is concerned that adding the task will add eleven weeks to the project. The stakeholder argues that the time will be less than eleven weeks. Who is correct? 7. Based on the information in number 6 above, how much longer will the project take? 79 GU, PMP Preparatory Course, MODULE 5

Answer 1 1. The length of the critical path is 18. There are two Answer 1 1. The length of the critical path is 18. There are two paths here; tasks 1, 2, 4, 5 and tasks 1, 3, 5. Tasks I, 2, 4, 5 are longest and are therefore the critical path. Their paths add up to 18, so the critical path is 18 weeks long. Follow the dark line on the diagram below. 80 • GU, PMP Preparatory Course, MODULE 5

Answer 1 (Continued) 2. Five weeks. Remember to do a forward pass through the Answer 1 (Continued) 2. Five weeks. Remember to do a forward pass through the network diagram (moving from start to finish) to find the early start and early finish for each task. A backward pass through the network diagram (moving from finish to start) is needed to find the late start and late finish. On the forward pass, task 1 will start at the beginning of week 1 and complete at the end of week 3. Task 3 will start at the beginning of week 4 and complete at the end of week 9. Now start the backward pass. Task 5 must end at the end of week 18 and needs to start no later than the beginning of week 15. Task 3 needs to be complete at the end of week 14. So, the latest task 3 can start is at the beginning of week 9. You can use either slack formula to compute slack. LF-EF= 14 -9=5 or LS-ES = 9 -4=5. There are many ways to calculate slack. Pick one you learned in project management class that works for you. 81 • GU, PMP Preparatory Course, MODULE 5

Answer 1 (Continued) 82 GU, PMP Preparatory Course, MODULE 5 Answer 1 (Continued) 82 GU, PMP Preparatory Course, MODULE 5

Answer 1 (Continued) 3. Zero, it is on the critical path. A task on Answer 1 (Continued) 3. Zero, it is on the critical path. A task on the critical path almost always has no slack. 4. Five weeks. There are only two paths in this example; tasks 1, 2, 4, 5 and tasks 1, 3, 5. The length of the non-critical path (tasks 1, 3, 5) is 13. The length of the project is 18 so 18 - 13 is 5. The total slack of the path with the longest float is 5. 5. It will have no effect. The length of path tasks 1, 3, 5 was 13. Adding 4 more weeks to the length of task 3 will make that path 17. Since it is shorter than the critical path, the critical path does not change. The length is still 18 weeks because task 3 is not on the critical path. 6. The stakeholder. 7. Six weeks longer. 83 GU, PMP Preparatory Course, MODULE 5

Test your knowledge about critical paths, float, etc Questions Answers Can there be more Test your knowledge about critical paths, float, etc Questions Answers Can there be more than Yes, you can have 2, 3 one critical path? Do you want there to be? Can a critical path run over a dummy? Why is a dummy included in a network diagram? or many critical paths. No, it increases risk. Yes. To show interdependencies of tasks. • GU, PMP Preparatory Course, 84 MODULE 5

Test your knowledge about critical paths, float, etc (Continued) Yes. Can a critical path Test your knowledge about critical paths, float, etc (Continued) Yes. Can a critical path change? Can there be negative float? Yes, it shows you are behind. Does the network diagram No, not automatically, but the change when the end date changes? project manager should investigate options such as fast tracking and crashing the schedule to meet the new date and then change the network diagram accordingly. Would you leave the project No, you would crash or fast with a negative float? track. • GU, PMP Preparatory Course, 85 MODULE 5

SHORTENING THE SCHEDULE (duration compression, page 75, see also resource leveling, page 76) Exercise SHORTENING THE SCHEDULE (duration compression, page 75, see also resource leveling, page 76) Exercise Based on the network diagram below, what would you to do during planning (or executing for that matter, while taking corrective action) to compress the schedule to 30 month 86 • GU, PMP Preparatory Course, MODULE 5

Answer 87 GU, PMP Preparatory Course, MODULE 5 Answer 87 GU, PMP Preparatory Course, MODULE 5

RE-ESTIMATING Once it is known that the schedule (or budget) must be reduced project RE-ESTIMATING Once it is known that the schedule (or budget) must be reduced project manager can investigate the task estimates that contain the most unknowns, eliminate or reduce these "risks" and thus decrease the estimate. 88 GU, PMP Preparatory Course, MODULE 5

CRASHING Adding more resources to critical path tasks while maintaining scope. This can take CRASHING Adding more resources to critical path tasks while maintaining scope. This can take the form of moving resources from non-critical tasks or adding extra resources to the task from outside the project. Crashing almost always results in increased costs. 89 • GU, PMP Preparatory Course, MODULE 5

FAST TRACKING Doing critical path tasks in parallel that were originally planned in series. FAST TRACKING Doing critical path tasks in parallel that were originally planned in series. Fast tracking often results in rework, usually increases risk and requires more attention to communications. For example, using the previous network diagram (from Exercise 2) what task would you fast track to shorten the project length? Task H (or any other pair of tasks on the critical path, assuming it is logical due to the nature of the work) could be fast tracked by making it occur at the same time, or in parallel with Task G. Task C could also be fast tracked by having part of it done concurrently with Task H. 90 GU, PMP Preparatory Course, MODULE 5

Test yourself on crashing and fast tracking! Exercise 1 Imagine that this project has Test yourself on crashing and fast tracking! Exercise 1 Imagine that this project has a project float of-3. Which task or tasks presented below would you crash to save three months on the project, assuming that the tasks listed below represent critical path tasks? 91 • GU, PMP Preparatory Course, MODULE 5

Exercise 2 1. Management has told you to get the project completed 2 weeks Exercise 2 1. Management has told you to get the project completed 2 weeks early. What is the BEST thing for you to do? A. Consult the project sponsor B. Crash C. Fast track D. Advise the customer (management) of the impact of the change 2. To handle the situation described in exercise 2, number A above, you could assign a more experienced resource to task Start-B in order to get the task done in seven weeks, but it would cost an additional $20, 000 to do so. You could eliminate part of Task C-D or E-End and save $5, 000 and 1 week of work. You could move work from Task A-C to Task B-E and save $2, 000. What is the cost of compressing this project? 92 • GU, PMP Preparatory Course, MODULE 5

Exercise 2 (Continued) • GU, PMP Preparatory Course, 93 MODULE 5 Exercise 2 (Continued) • GU, PMP Preparatory Course, 93 MODULE 5

RESOURCE LEVELING (page 76) Leveling lets schedule and cost slip in favor of having RESOURCE LEVELING (page 76) Leveling lets schedule and cost slip in favor of having a stable number of resources each month. A little-used tool in project management software, leveling allows you to level the peaks and valleys of resource use from one month to another resulting in a more stable number of resources used on your project. 94 • GU, PMP Preparatory Course, MODULE 5

Definitions SCHEDULE MANAGEMENT PLAN Once the schedule is developed, the project manager can and Definitions SCHEDULE MANAGEMENT PLAN Once the schedule is developed, the project manager can and must put in place a plan for effectively managing the project to the schedule and for managing changes. Such a plan can be formal or informal but is part of the project plan. This plan would include: Establishment of a schedule baseline for measuring against during project control A plan for how schedule variances will be managed Identification of schedule change control procedures Identification of performance measures 95 GU, PMP Preparatory Course, MODULE 5 (page 78):

Definitions (Continued) HEURISTICS: (page 76) A heuristic means a rule of thumb. Several types Definitions (Continued) HEURISTICS: (page 76) A heuristic means a rule of thumb. Several types of heuristics exist; some are scheduling, estimating, planning and resource leveling. One such heuristic is the 80/20 rule that, in quality, suggests that 80% of quality problems are caused by 20% of potential sources of problems. VARIANCE ANALYSIS: dates with planned. 96 GU, PMP Preparatory Course, MODULE 5 (page 80) Comparing actual

Practice for the CAPM® and PMP® Exams Project Time Management 97 GU, PMP Preparatory Practice for the CAPM® and PMP® Exams Project Time Management 97 GU, PMP Preparatory Course, MODULE 5