Project Management Mid-Term 2
Criticality Index
An estimation of the probability an activity will fall on the critical path, as generated by computer simulations of activity durations. A high criticality index indicates there is a high likelihood the activity in question will fall on the critical path.
Explain the difference between a project that has a fixed delivery day and one that has a fixed limit on resource usage. Why might a Project Manager be interested in this difference?
-A project with a fixed delivery date can vary the level of resources used to meet a firm project completion date. -A project with a fixed limit on resource usage cannot obtain additional resources but can possibly delay the project completion date. -The reason this distinction is important is that it specifies which of the fundamental trade-offs the project manager can exercise. In the case of projects with fixed delivery dates, only performance and cost (resource usage) can be varied. In projects with fixed resource usage levels, only schedule and performance can be varied.
What does it mean to say that project monitoring and control are on the opposite sides of project selection and planning?
-Project selection and planning specify the goals for the project. The plan also details what activities and schedule must be met; things the project manager must control. -Project monitoring and control seek to ensure that the project is making progress toward the achievement of these goals.
Tools for Assessing Project Uncertainties
-Risk Mapping -Failure Modes and Effects Analysis (FMEA) -The Gut-Feel Method -The Delphi Method -Fishbone Diagrams -Simulations
Reasons for Schedule Modifications
-To meet a customer-specified due date -To ensure the final product hits a market window -To delay cash outflows -To accommodate resource limitations -To respond to an emergency or crisis -To compensate for schedule delays during project delivery -To respond to cost overruns during project delivery -To respond to customer or technical requirements not initially considered
The Delphi Method for Uncertainty Assessment with Virtual Teams
1) Brainstorming, Round 1 - In the first round, the facilitator asks team members to list the unfavorable uncertainties (risks) and favorable uncertainties (opportunities) that could potentially arise in relation to each project deliverable. Facilitator directs the team to consider potential uncertainties - events not currently expected or assumed as project outcomes or goals 2) Compilation of Round 1 - Facilitator compiles Round 1 results, consolidates similar items and sends them back to participants without identifying who said what. In the next round, participants review the consolidated list and suggest items to add, delete, or clarify. The process can have 2 or 3 iterations, but, ultimately an agreed-upon list emerges 3) Ratings - To obtain likelihood and impact information, the facilitator can engage participants in a rating process similar to the one used in FMEA (To keep things simple, it may be appropriate to include likelihood and impact ratings but omit the rating for difficulty of detection) This will result in multiplicative scored ratings that enable participants to see which uncertainties are worthy of further consideration. Further online or telephone discussion will help to clarify assumptions 4) Selection of Uncertainties and Discussion of Strategies - The next step, also handled interactively, is to engage team members in a numerical voting process to select the most important uncertainties. They may consider the numerical ratings from Step 3 but also incorporate insights gained from online / telephone discussions 5) Ideas for Preparation - Once the most important uncertainties have risen to the surface, virtual team members submit ideas for preparing or responding to them 6) Compilation of Results - The facilitator compiles the results of the process and submits them to the team for final review. Once the team reaches agreement, the project manager makes the appropriate revisions to the project plan
Identifying Critical Path and Float Using ES, EF, LS and LF Information
1) Critical Path activities are those activities for which Early Start (ES) = Late Start (LS) and Early Finish (EF) = Late Finish (LF) 2) Total Float (TF) for any activity = LS - ES, which is equivalent to LF - EF --> If unequal, mistake was made 3) Free Float (FF) for any activity = Difference between the EF of that activity and the earlier ES of all activities immediately following it. -In other words, note the EF of each task in the network. -Wherever there is a difference between the EF of one activity and the earliest ES of a successor, there is free float. -Free float always appears where a shorter path merges with a longer path
Milestone
An event in a project designating the point at which a related set of activities has been completed, or at which a set of activities may begin.
Unknown Unknown
An event that still may occur as a surprise in a project, even after the team has performed a thorough uncertainty analysis and identified known unknowns.
Late-Start Schedule
A schedule in which all project activities are delayed to their latest possible start times
Gambler's fallacy
A bias related to the inaccurate statistical expectations people place on random event patterns. In a project environment, unrealistic statistical expectations could lead people to believe a string of bad luck will even out, and therefore underestimate the likelihood that unfavorable conditions will continue. Such expectations could influence a team assessing project risks or making go-no-go decisions in the context of a series of failures within a project.
Critical Path Method (CPM)
A scheduling approach developed and used by Du Pont in the 1950s to bring order and substantial time compression to projects involving the closure of chemical plants during routine maintenance procedures. -Pays attention to the cost of the project and its completion time
Theory of Constraints
A conceptual framework and set of tools aimed at identifying and managing constraints or bottlenecks in processes. According to advocates of TOC, the constraint in a project is defined by the critical chain, which is a function of resource availability.
Network Diagram / PERT - CPM Chart
A diagram that shows sequential and concurrent relationships among activities in a project.
Outcome:
A dimension of uncertainty analysis, the outcome is the consequence of the event that a favorable or unfavorable uncertainty creates.
Uncertainty Source
A dimension of uncertainty assessment, the source is typically considered as the root cause or driver of an uncertainty. Five categories of uncertainty sources include: Financial, Technical, Business Environment, Social, and External or Natural Environment. -Financial - unfavorable = financial conditions threaten success of the project -Financial favorable = enhance viability / outcome of project -Technical unfavorable - technical challenge could alter course of the project in a negative way -Technical favorable = technical breakthrough could alter course of project in positive way -Business environment unfavorable - market, political, regulatory condition make project outcomes less attractive -These same outcomes could make project outcomes more attractive -Social unfavorable = project challenge associated with potential stakeholder interference in the project. -Unexpected support for project from a stakeholder group might help project advance -External or Natural Environment - acts of nature such as disease, epidemics, floods, earthquakes, tornadoes could negatively impact project or could make project unexpectedly easier to execute
Likelihood:
A dimension of uncertainty that project teams must consider, along with impact, when determining which uncertainties are worthy of attention. Likelihood is a subjective estimate of probability, based on opinion and judgment. In the absence of reliable historical data, teams can use consensus-based or voting methods to enhance their ability to forecast likelihood.
Normal Distribution
A distribution of numbers that is bell-shaped and has tails of equal size extending from either side of the modal/mean value.
Megaproject / Program
A large-scale, long duration project that involves many deliverables or milestones.
Critical Path Algorithm
A mathematical algorithm used for assessing the location of the critical path, free float, and total float on a network schedule. 1) It involves making a forward pass through the network to determine the earliest possible start and finish times for each activity. 2) Then taking a backward pass to determine the latest possible start and finish times for each activity. 1) Start Time for Starting Node = 0 2) Early Start (ES) for all starting activities (no predecessors) = 0 3) ES for any other activity = Maximum or latest Early Finish (EF) for all activities that immediately precede the activity. Especially relevant at merge points where one activity has several predecessors 4) Early Finish (EF) for any activity = ES + Estimated Activity Duration 5) Total Estimated Project Time = Latest EF for any activity in the network (in other words, EF for the latest-running activity at the end of the network or the final milestone)
Person-Months
A measure of (the number of persons required) X (the number of months of work per person).
Line-of-Balance Method
A method developed in the 1950s for measuring the status of production in manufacturing sites, and a precursor to modern scheduling techniques and network diagrams.
Program Evaluation and Review Technique (PERT) or Three-Point Estimates
A method for calculating probabilistic task time estimates first used by the U.S. military and based on three time estimates given for each task: an "optimistic" time estimate t(o), a "pessimistic" time estimate t(p), and a "most likely" time estimate t(m). PERT uses the following equation to calculate an expected time estimate: t(e) = t(o) + 4 t(m) + t(p) 6 -Developed by Navy to help with Polaris Missile Program -US wanted to complete it as quickly as possible -PERT enabled Navy to estimate completion times within a range -To comply with requirements of PERT statistical analysis, we assume the time required for each activity is an uncertain and random variable - must take on any value within the range specified by t (o) and t(p) -Time required need for each activity need to be independent -Estimate Duration Probabilities Z Score = D(esired / Specified Time) - T(e) / Standard Deviation
Tabletop Exercises
A method of project simulation that involves miniature props or mockups representing the physical facilities where a project event will occur. Team members use the physical representation to help them imagine the scenario and envision possible the circumstances. They brainstorm critical uncertainties for which they feel ill-prepared and develop contingency plans.
Physical mock-up:
A method of project simulation that utilizes a three-dimensional representation of a product for assessing design concepts, examining physical compatibilities, or testing physical properties during the design phase of product development.
Rolling Wave Planning
A method of scheduling or planning used in large projects with many phases or milestones, where details about work to be done in the distant future are not developed until early work has been completed and the team has the necessary information to define later work elements.
Float / Slack
A metric used in project scheduling to indicate: -The length of time that a task not on the critical path can be delayed without jeopardizing the schedule. -Negative Float = initial schedule specifies a completion date later than the due date. Unless the due date is negotiable, team must consider methods for getting float back into a neutral or positive position by compressing activities
Early Start Schedule / Early Start Time
A network schedule in which every activity is set to begin at its earliest possible start time & The earliest possible time an individual activity may begin, given its predecessors.
Time Based Network
A scheduling display tool that combines the advantages of networks (e.g., AOA or AON diagrams) and bar charts (e.g., Gantt charts) and provides a visual illustration of critical path and float in a project. -Red Path highlighted represents the critical path -Dashed Arrow / Lines represents Float or Slack -The length of each arrow represents the duration of the activity -will identify each activity and # of team members it will require per week
Fast-Tracking
A scheduling tactic whereby tasks normally done in sequence are overlapped to some extent in order to compress a project schedule. -Usually associated with start to start precedence relationships -Fast tracking can be applied independently or in combination with crashing and scope reduction to shorten a project's duration -Can introduce risks and increase coordination challenges, but is common in hypercompetitive, short product life cycles, new product development environments
Gantt Chart / Bar Chart
A scheduling tool that displays project activities as horizontal bars on a time scale. The Gantt chart makes it easy to see when activities are scheduled, but does not depict dependency relationships concretely. -Popular because of its simplicity and ease of use -Hard to make adjustments to project schedule because Gantt charts don't reveal sequential relationships, the critical path or float --> need network diagram for cross-checking -Excel-based Gantt Chart shows, numerically and in histogram form, what the resource loads are each week
Risky Shift
A social-psychological phenomenon in which individuals tend to increase their willingness to accept risk, beyond their innate level of risk tolerance, after engaging in group discussion about an action under consideration. -Research shows that individuals wouldnt pursue these risky actions without the discussion -It can lead reluctant team members to go along with a good idea they had initially feared. On the other hand, it could lead a team to make a foolish choice because of groupthink effects. -A well-structured, balanced discussion will be important to the team in making the best decisions and avoiding risky shifts
Lag / Delay
A specified amount of waiting time designated between sequential activities in a finish-to-start relationship. The second task in the sequence can begin only after a certain amount of time has passed after the first task in the sequence has finished.
Standard Deviation
A statistical measure of the variability or dispersion of a data set. The concept is applied in the PERT method for estimating activity and path durations and associated probabilities. -For a beta distribution = Pessimistic Time Estimate = T (p) - Optimistic Time Estimate T (o) / 6
Central Limit Theorem
A statistical theorem which states that regardless of the shape of a population's distribution, a sufficiently large random sample from that population will have a normal distribution with a bell-shaped curve. -Outcome of PERT = t(e) is normally distributed variable with uniform, uni-modal, bell-shaped curve
Six Sigma
A systematic approach for planning and managing quality management and quality improvement projects. Several tools within Six Sigma can be applied to projects of all types, regardless of whether or not they involve quality improvement.
Known unknown:
A term used to describe uncertainties for which a team has anticipated and planned carefully.
Activity on Arrow (AOA) Diagram
A type of network schedule display used to show when activities will occur during a project and also to make clear the sequential relationships between activities. In an AOA diagram, -Activity information (including a description of the activity and its estimated duration) appears on connecting arrows or arcs; -Nodes (which can be represented by boxes, circles, or other two-dimensional shapes) represent the beginning and ending points of activities. -One distinguishing feature of AOA networks is that in some configurations they require what are known as dummy activities (defined later in this glossary). -Dummy activities are represented by dashed arrows or lines in AOA Diagrams
Activity on Node (AON) Diagram
A type of network schedule display, similar to an activity-on-arrow diagram, used to show when activities will occur during a project and also to make clear the sequential relationships between activities. In an AON diagram: -Activity information (including a description of the activity and its estimated duration) appears inside nodes (which can be represented by boxes, circles, or other two-dimensional shapes) -Arrows between nodes indicate the sequential relationships among activities to be performed in the project. -Hexagons instead of boxes represent milestones -
Monte Carlo Simulation
A type of simulation with a wide range of applications. In a project scheduling application, Monte Carlo methods use a software program to generate random numbers for activity times based on specifications such as distribution type, mean, and range. The results of such simulations are time estimates for project tasks and paths, as well as criticality indices.
Non-critical Activities
Activities in a network path that do not fall on the critical path and thus can be delayed somewhat without jeopardizing the project schedule.
Fishbone diagram
Also known as Ishikawa diagram or cause-and-effect diagram. In the context of uncertainty analysis, it is used as a structural framework for brainstorming potential causes of an identified risk. Possible causes are organized into a few general categories, and further research is needed later to determine whether the identified causes are the actual reasons for the problem or opportunity. -Fishbone diagrams will probably not stand alone as an uncertainty assessment tool, but it can be used as an adjunct to risk mapping, Delphi, Gut-Feel, FMEA
The arrival and departure times of commercial aircraft are carefully scheduled. Why, then, is it so important to have excess capacity in the airport control tower?
Although the arrival and departure times may be carefully scheduled, we all know that actual arrivals and departures often deviate significantly from these schedules. Therefore, a significant amount of uncertainty is present and greatly complicates the ability of the airport control system to handle arrivals and departures. Indeed unplanned events (e.g., weather delays, equipment malfunctions, late flight crews, and so on) often cascade through the system further compounding the problem. Therefore, excess capacity in control towers is needed as a buffer given this level of uncertainty. Clearly, the cost of not having this capacity greatly exceeds the cost of some idle capacity.
Simulation
An approach for tackling project uncertainties, and defined by The American Heritage College Dictionary as "Representation of the operation or features of one process or system through the use on another," simulation generally engages the use of technical methods to understand the behavior of a product or process, but can use other, physical representation methods such as dress rehearsal, physical mock-up and tabletop exercises. -For project environments, simulation models can be useful when a full set of technical and financial risks is understood when outcomes can be quantified (cost, time, technical failure) and when probability distributions are known with relative certainty. -Believe the tools are too often used without input from team-based tools - consequently a quantitatively based analysis, regardless of its rigor, may not include all possible / relevant uncertainties. -All these tools cannot necessarily help a team envision the circumstances under which the project will ultimately operate. Simulation Applications for Project Uncertainty: -Physical Mock-Ups - a 3-D representation of a product - can be used to assess the characteristics of a product in ways not possible with a computerized 2D or 3D drawing -Dress Rehearsals -a practice run for an event or activity -Tabletop Exercises = engage team members in imagining a scenario and placing themselves into the circumstances (details below) -Market Tests and Clinical Trials = team-oriented simulations intended to represent eventual realities for products. Both require extensive customer involvement, and the team's effective use of the results will determine their value. -Technical Simulation = New product efforts in technical environments often involve 3-D simulations of designs - Allows a design team to see where interferences potentially exist among structural elements, reducing the chances the problem will be discovered too late to fix in a economical manner -System Dynamics Modeling = describes a general set of simulation tools that allow users to examine the relationships among a constellation of interrelated social and technical variables. Such models can incorporate real data or they can use subjective data generated by the user. Overuse of such models might distract a team from conducting project business, models may be worthwhile in the context of highly complex projects with multiple implications -Monte Carlo Simulation = Software tools such as @Risk or Crystal Ball use Monte Carlo simulation to assess risk profiles associated with time, cost and other factors - Common application assesses probabilistic time estimates to gain insights into the range and distribution of project completion times
Gut-feel method:
An interactive and visual method used for uncertainty assessment in team settings that can be adapted to include both favorable and unfavorable uncertainties. Teams brainstorm ideas about the likelihood and impact of uncertainties, vote using adhesive-backed colored dots to signify likelihood and impact, and visually identify the most significant uncertainties for further discussion and preparation. -Value of gut-feel comes from its use of group input to generate ideas and estimate likelihood / impact. -Research has demonstrated that groups make more accurate judgments about uncertain events than individuals do 1) Identify Deliverables = using WBS mind map or outline as starting point, record each major deliverable 2) Brainstorm Uncertainties = Members individually brainstorm potential uncertainties associated with each deliverable. Write down favorable uncertainties in one color, unfavorable in another color. Working alone is critical to stimulating team members and casting a wide net around possibilities - consider 5 risk sources - financial, business environment, social, natural environment, technical 3) Combine Uncertainties = Team members place favorable and unfavorable risk notes next to corresponding deliverables, working collaboratively to eliminate duplicates. Can add new uncertainty statements as exercise triggers ideas 4) Discuss Uncertainty Meanings / Outcomes = Team reviews each uncertainty to ensure intended meanings are clear. Team discusses possible outcomes for each uncertainty. 5) Assess Likelihoods with Dot Voting = Each team member puts red dot with highly likely uncertainty, yellow dots with moderately likely uncertainties. Team members work silently / dont talk and avoid influence each other 6) Assess Impacts with Dot Voting = Using same process, each team member puts blue dots next to any uncertainty that will have a major impact on the project and a green dot for a moderately impactful uncertainty 7) Assess for Significance or Relevance = At the end of voting, team considers which uncertainties are most relevant - relevant items are generally those with patterns of colored dots indicated high likelihood and significant impact - these are moved to a designated column 8) Discuss Root Causes and Drivers = Team considers forces underlying uncertainties selected as relevant. For unfavorable risks, brainstorm potential root causes - factors that could potentially cause this risk and its associated outcomes. For favorable UCs, brainstorm key drivers - factors that would be likely to cause this to happen. Sometimes this will require a longer discussion or fishbone diagram 9) Consider Actions = Drawing from the discussion of root causes and key drivers, the team brainstorms possible actions for 1) enhancing favorable opportunities 2) mitigating high-likelihood undesirable risks and 3) creating contingency plans to prepare for uncertainties that can't be controlled. Facilitator plays important role in guiding this process. If list of relevant uncertainties is somewhat large, can be useful to break the group into smaller subteams and have each one generate ideas for addressing the uncertainties associated with a particular deliverable 10) Assign Responsibility = Determine who is responsible for each action and add these actions to the WBS / responsibility matrix where appropriate 11) Develop a plan to monitor uncertainties = The facilitator asks the question, "How will we know if any of our relevant uncertainties materialize?" Team brainstorms ideas for monitoring each uncertainty 12) Summarize the Results of the Analysis in a Risk-Response Matrix = The risk-response matrix extracts key findings from the gut-feel process and summarizes them in an electronic document available to all team members for review, approval and continued use during the project.
Project Risk
An uncertain event or condition that, if it occurs, has a positive or negative effect on a project's objectives.
Beta Distribution
As part of the PERT three-point time estimate method, a beta distribution can be determined from only three time estimates, and allows more flexibility than a normal distribution because it does not have to be symmetrical and thus can be skewed to the right or left.
Backward Pass
As part of the mathematical logic used in the critical path algorithm -The backward pass involves calculating the late finish and late start for each activity -Starting with the ending project activity or milestone and working backward through the network toward the beginning of the project. 1) Late Finish (LF) for last activity or milestone = Latest EF for any activity or milestone in the network 2) Late Start (LS) for latest EF activity or milestone = LF - estimated activity duration 3) LF for any activity = Earliest LS for all activities that follow it. Especially relevant at burst points where one activity has several successors 4) LS for any activity = LF - estimated activity duration
Forward Pass
As part of the mathematical logic used in the critical path algorithm, the forward pass involves calculating the earliest possible start and finish time for each activity, beginning with the all starting activities and working toward the end of the project.
Applying Simulations
Before the Project or Early in the Project: (Team-Based Creative Tools) -Physical Mock-Ups, -Rehearsals or Dry-Runs -Tabletop Exercises (Analytically Based Tools) -3-Dimensional Design -Wind Tunnel Tests on Preliminary Designs -System Dynamics Modeling -Monte Carlo Simulation During the Project after Some Conceptual and Design Work is Completed (Team-Based Creative Tools) -Market Tests -Clinical Trials (Analytically Based Tools) -Test software on Sample Data -Wind Tunnel Test on a More Fully Developed Prototype
Availability Heuristics Bias
Describe human processes of recall based on vividness and recency. If a potential occurrence has happened to us recently, been in the news, we are likely to overestimate its likelihood
Conjunctive Events Bias
Individuals tend to overestimate the probability of conjunctive events occurring. Conjunction occurs when several things all must happen or when several attributes all must be present. There is no compensation or tradeoff. In a project environment, an example of a conjunctive event would be an activity dependent on the merger of several predecessor activities being completed on time, but might not intuitively apply joint probability statistical models to predict the likelihood of all of them being completed by a specified date. Say its 90% likely to start when its really 90% x 90% x 90%
Unfavorable Project Risks
Events or occurrences not currently within the project team's expectations that have the potential to undermine the success of a project.
Risk-Response Matrix
Extracts key findings from the gut-feel process and summarizes them in an electronic document available for all team members for review, approval and continued use during the project. -Gives short summary or full description of the favorable / unfavorable uncertainty -Explains how the team will prepare for it, what must be added to the WBS, what do team members need to keep in mind -Highlights contingency plans - what is the backup plan if the unfavorable uncertainty arises despite preparation? What is the backup plan if the favorable uncertainty does not appear despite the team's best efforts? -Trigger = What evidence will indicate this uncertainty has occurred, is occurring or is imminent? -Team Member Responsible = Who will take responsibility for preparing for this uncertainty? Who will develop and execute the contingency plan, should it become necessary?
FMEA (Failure Modes and Effects Analysis)
FMEA was originally developed as a systematic, team-based analytic process for examining what could go wrong with a product or a routine production process. FMEA has been adapted for use in planning projects as a tool to aid a team in identifying potential risks and assessing their significance using numerical scoring. -prescribed component of Six Sigma - 1) Foundation = Team begins with FMEA only after it has developed a WBS and members have shared understanding of project goals / expected outcomes 2) Individual Brainstorming = Team members work alone to brainstorm possible failure modes for the project, accounting for things that could happen during the project that would cause execution to fail or risks associated with project's final product 3) List Failure Modes = A facilitator uses a round robin approach to gather failure mode ideas from participants - these are listed on left side of board / paper 4) Understand Meanings and Causes = Group Discusses the meaning, causes and effects of each failure mode listed. The facilitator writes key info about each one in the column just to the right of the failure mode list. Activity helps group develop shared understanding of each risk 5) Rating = Team rates each failure mode for severity, likelihood and difficulty of detection on scales of 1-10, 10 is high. Facilitator can ask each person to complete their own ratings, then generate an average or consensus. 6) Calculate Risk Priority Numbers (RPNs) = Team members multiply their three ratings for each failure mode to derive a score for each one. Facilitator calculates group averages 7) Prioritize and Discuss = Some failure modes will emerge as higher priorities for action, based on their RPN scores. Team should carefully review the ratings and underlying assumptions to ensure there are no serious flaws in logic. Given the multiplicative nature of the calculation, a small overestimate in one of the numbers can can result in an exaggerated RPN. Thus, the team might wish to make adjustments before agreeing on final priorities 8) Decide on Actions = Team has agreed on most important risks based on RPNs, facilitator can guide members in discussion of actions to limit negative outcomes, who will be responsible, how to monitor the failure mode and what contingency plans to establish
What does it mean to "fast track" a project?
Fast-tracking is a technique whereby key stages of the project are overlapped. In the construction industry, this might entail beginning construction before the design and planning are finished. In the pharmaceutical industry this may entail developing the production process as the new drugs are being developed and tested.
Feeding Buffer
Feeding Buffer = A segment of float intentionally scheduled at points where noncritical chain activities merge with critical chain activities. -It places a limit on the extent to which a non-critical task may consume float by being delayed.
Types of Precedence Relationships
Finish-to-Start = A sequential relationship between tasks whereby the second task in the sequence can't start until the first task in the sequence has finished, either immediately after the first task has finished or after a specified lag. -Lag or Delay = A specified amount of waiting time designated between sequential activities in a finish-to-start relationship Finish-to-Finish = A sequential relationship between tasks whereby the second task in the sequence can't finish until a specified time after the first task in the sequence has finished Start-to-Finish = A sequential relationship between tasks whereby the second task in the sequence cannot finish until a specified time after the first task has started. Start-to-Start = A sequential relationship between tasks whereby the second task in the sequence cannot start until a specified time after the first task has started. This type of sequential relationship is often used for fast-tracking schedules.
Why is the problem of allocating scarce resources to a set of projects similar to the problem of scheduling a job shop?
In a job shop allocating resources (equipment and workers) to jobs or orders is required. In projects, a similar allocation is required where specific resources must be allocated to tasks and activities which represent the jobs.
Resource Buffer
In critical chain terminology, this is an agreed-upon date on which team members whose tasks run sequentially will meet to discuss the progress of their work. This offers an opportunity for an early warning if the first task is running late, and elevates the problem so the project manager and team members can provide assistance. provides information-based protection for critical chain activities. -A time designated within a critical chain activity whereby the owner of that activity shares information about the progress of the current activity with the owner of the subsequent critical chain activity. -The resources buffer is set at a certain number of days prior to the scheduled end of the critical chain activity underway -By sharing this information prior to the end of the activity, problems or possible causes for delay might be resolved. This helps mitigate the the risk of delay to the project.
Explain why project-oriented firms require excess resource capacity
In project oriented firms there is much more uncertainty about the timing of resource needs since the resources primarily move between projects rather than moving between projects and a functional department. Therefore, extra resource capacity is needed as a buffer given the greater level of uncertainty present.
Probabilistic Analysis
In project scheduling, an analysis that applies statistical concepts to determine probabilities of task durations and other parameters based on three-point time estimates.
List as many things as you can think of that should be entered into a specific resource's calendar.
Information that should be entered into a resource's calendar include: -The resource's availability (e.g., days in week available, total hours available per week, hours available each day). -Times the resource will not be available (e.g., lunch, weekends, holidays, vacations, scheduled maintenance), and -Resource cost (e.g., cost per unit of usage, cost for overtime and overuse, known changes in future resource cost).
Why is it probably a good idea to avoid periodic reports, except in specific cases such as reports tied to the organization's accounting system?
It is probably a good idea for two reasons: -It is more appropriate to let schedules, milestones, scope changes, problems, and the project team's general need for information dictate the timing of reports. -There is a tendency for recipients to ignore periodic reports.
Uncertainty Responses
Modify Exposure = -Mitigate (reduce the likelihood or negative effect of unfavorable uncertainties) -Enhance (increase the likelihood or positive effect of favorable uncertainties) Shift Ownership = -Transfer risk of unfavorable uncertainties to another party -Share opportunity of favorable with another party Eliminate this uncertainty or Ensure its Occurrence = -Avoid Unfavorable (Change project plan to eliminate the threat entirely) -Exploit favorable (Change project plan to ensure opportunity becomes a reality) Accept and Prepare = -Accept potential for risk of unfavorable, develop contingency plans -Accept potential for favorable, prepare to take advantage if it emerges
Overconfidence Bias
Once they have made estimates, people tend to be far more confident than they should be about their accuracy. This has serious implications for the estimations project participants make about the impact and likelihood of potential uncertainties. Fortunately, group judgments tend to be more accurate than individual judgments, but unfortunately, groups are just as subject to overconfidence bias as individuals are, particularly in instances when groupthink rules. The result can be that a team wears blinders when it comes to seeing risks that might cause schedule slippages or cost overruns
When allocating scarce resources to several different projects at the same time, why is it important to make sure that all resource calenders are on the same time base (i.e. hourly, daily, weekly)?
One reason it is important to ensure the resource calendars are on the same time base is because task duration is not usually dictated by the number of labor hours required to complete the task, but rather by the calendar time required to complete it.
Aside from the obvious benefits for project control, what other benefits might result from a good project reporting system?
Other benefits from a good project reporting system include: -Less wasted time reporting information that is not used. -Better informed team members and stakeholders, and -A better record of the project that can be used to facilitate future project planning.
Key Contributions Stemming from the Project Schedule
Outcomes of the Project Scheduling Process: = Highlights Uncertainties --> -For Managing Stakeholder Expectations -For Team-Based Risk Analysis = Establishes Foundation --> -For Further Schedule Modification -For Monitoring System = Enhances Team Understanding and Perspective --> -By Uncovering Members' Assumptions -By Providing a Basis for Goal Commitment = Sets and Manages Expectations --> -With Client -With Key Stakeholders -With Sponsor
Allocation Problems
Overallocation = A situation in which necessary resource requirements exceed the availability of team members. Underallocation = A situation in which the resources available exceed the project requirements at a specific period of time. Some workers or other resources would be idle during a period of underallocation.
Misconceptions of Chance Bias
People are not good mental statisticians and tend to make statistical inferences based on cognitive biases about how random event patterns should appear. Coin tosses - might be inclined to estimate higher likelihood the next toss would something because you have subconscious that Heads / Tails should even out - this can lead to project managers to believe a string of bad luck will even out - as a consequence, they underestimate the likelihood of unfavorable circumstance continuing
Project Uncertainty Assessment Process
Possible Uncertainties: -Gather information about possible uncertainties - Consult historical data, interview experts, conduct team brainstorming --> Assess root causes or drivers of uncertainties -Likelihood = Determine the likelihood of this uncertainty-Identify and obtain data to help in the assessment -Impact = If this happens, how will it affect the project mission and goals? Will the impact be favorable or unfavorable? --> Consider team and organizational risk preferences -Relevance = Determine if the uncertainty is relevant for further consideration -Actions = Generate possible actions for addressing relevant uncertainties -Responsibility = Decide who will be responsible for each action -Monitor = Decide how to monitor this uncertainty
The Monitoring System is the direct connection between project planning and control. Why is this true?
Project planning specifies the activities, resource usage, and the goals for the project while control seeks to ensure that the project is making progress toward the achievement of these goals. Monitoring is concerned with collecting and reporting information. As such, monitoring connects planning and control in that the plan specifies the types of data that need to be collected and the reporting becomes the basis of control.
Precedence Relationships
Relationships between activities that determine the sequence in which the activities will be performed.
Retrivability Bias
Retrievability describes a pattern of human judgment biases based on familiarity. If a risk, opportunity or issue is easy for us retrieve because of our mental models, we will be more likely to recall it and associate it with the project
The Delphi Method
Risk-mapping, FMEA and gut-feel approaches work well when project manager can gather core team and critical stakeholders in same room / take advantage of the synergies and commitment derived from face-to-face interaction -Delphi Method is an interactive approach for involving dispersed experts in forecasting that can be adapted for project uncertainty analysis -Delphi offers the advantage of bringing together a larger group than might be practical in an on-site session and it opens the possibility of tapping into insights from external experts. -Takes anonymous inputs, Delphi reduce the likelihood that a high-status person overrides others and creates bias results. -However, it will not engage participants to the extent an on-site meeting does. A team can compensate for this by using collaborative Web-based tools / scheduling people to meet virtually at a specified time.
Concepts for Project Scheduling
Schedule Display Formats = -Activity-on-Node (AON) Diagrams -Activity-on-Arrow (AOA) Diagrams Level of Detail = -A high-level milestone schedule is used for big-picture thinking about project plans & progress - necessary for megaprojects or programs -Milestone: An event in a project designating the point at which a related set of activities has been completed, or at which a set of activities may begin -A highly detailed schedule will depict the sequence and timing of individual tasks Types of Network Logic = -Soft Logic - A sequential relationship between activities that can be arranged in a number of ways, depending on the project manager or team's preferences, resources available or other circumstances -Hard Logic - A mandatory sequential relationship in which an activity must absolutely be completed before a successor activity may begin -In creating the initial schedule, adhere to hard logic first to avoid building false dependencies based on initial assumptions about resource availability or other circumstances that later may prove to be incorrect. Types of Precedence Relationships -Finish-to-Start -Finish-to-Finish -Start-to-Finish -Start-to-Start
Consequences of Negative Uncertainties
Schedule delays -cost overruns -reductions in quality -project abandonment -physical or psychological harm to people -damage to facilities or the environment -loss of reputation
Resource-Constrained Allocation Problems
Scheduling problems that arise when the resources available within a certain time period (e.g. day, month) are limited. To solve these problems, the project manager must delay one or more activities. Very often, realistic solutions to resource constraints involve delaying a project beyond its originally scheduled completion date.
Student Syndrome
The "student syndrome" refers to situations in which people wait until the last possible minute to begin a task. Its name is derived from the belief that students often delay the start of an assignment until just before it is due. -The tendency for project team members to delay the start of their work until the last minute. This can create situations in which schedule buffers disappear and the critical path and critical chain are jeopardized. The student syndrome is one of several phenomena that affect project delivery and cause actual performance to depart from planned performance.
Explain the difference in problems faced by a Project Manager who is short of secretarial resources and one who is short of a "Walt"
The PM that is short of secretarial resources does not face that great of a problem as this type of resource is relatively abundant and not usually critical to the project's ultimate success or failure. The PM that is short of a "Walt" (i.e., an individual with expertise and knowledge in an area) faces a much more daunting problem because a Walt is a scarce resource that is important to the project's successful completion and there are no readily available substitutes for a Walt.
Critical Chain
The actual sequence of deliverables, activities, tasks, or work packages that cannot be delayed without delaying the project. -While similar to the critical path concept, the critical chain adds another layer of complexity by taking into account resource availability. -Critical Chain - based on book by Eliyahu Goldratt - also wrote the Goal (Theory of Constraints) - theorized that managing any operation (service, manufacturing, project) effectively requires us to focus our attention on system constraints -In the Goal / factories --> the constraint is the bottleneck, for projects, the constraint is the critical chain Tips for Managing for Managing the Critical Chain: 1) Give Priority to the Critical Chain -manager must negotiate with functional managers to ensure people required for critical chain tasks are available precisely when needed. -Manager must articulate significance of critical chain, show flexibility with respect to personnel needs for activities not on the critical chain to convince functional managers to provide critical team members at necessary times -If team members are assigned full time to the project, manager has more control --> but needs to go out of their way to ensure people on this chain have all of the resources (material, equipment, support) necessary to succeed 2) Use Schedule Buffers to Protect Critical Chain -3 Types of Buffers: 1) Feeding Buffers = segments of float intentionally scheduled at points where noncritical chain activities merge with the critical chain --> activities with float should be delayed as long as possible to postpone expenditures, provide better cash flow management. Feeding buffer places limits on an activity being delayed too far to the point that it collides with critical chain and adds schedule risk. 2) Resource Buffer = provides information-based protection for critical chain activities. -A time designated within a critical chain activity whereby the owner of that activity shares information about the progress of the current activity with the owner of the subsequent critical chain activity. -The resources buffer is set at a certain number of days prior to the scheduled end of the critical chain activity underway -By sharing this information prior to the end of the activity, problems or possible causes for delay might be resolved. This helps mitigate the the risk of delay to the project. 3) Project Buffer = The time between a project's anticipated end date and the due date specified by the customer. -Project Buffers are often used in lieu of buffers within individual activities, which allows for the sharing of buffer time between all team members. 3) Beware the Effects of Multitasking -critical chain concept focuses on how people's work time is scheduled. Many times, employees belong to functional organizations / departments and their work time is loaned out to several projects. -If assigned to a multitude of projects simultaneously, much of their time can be unproductive switching between projects - there are setup times required to change mindset, prepare the right materials and figure out where you left off. -Data shows number of projects per engineer worked on, the amount of value-added time per project declines dramatically -Also research - person's effective intelligence actually declines under multi-tasking conditions
Free Float
The amount of time by which an activity can be delayed from its early start time without delaying the early start of any activity that immediately follows it. Free Float (FF) for any activity = Difference between the EF of that activity and the earlier ES of all activities immediately following it. -In other words, note the EF of each task in the network. -Wherever there is a difference between the EF of one activity and the earliest ES of a successor, there is free float. -Free float always appears where a shorter path merges with a longer path
Total Float
The amount of time by which an activity can be delayed from its early start time without delaying the project beyond its anticipated end date. Total Float (TF) for any activity = LS - ES, which is equivalent to LF - EF --> If unequal, mistake was made
List and describe the 3 most common criteria by which to evaluate different resource allocation priority rules
The three criteria are: -Schedule slippage ... a measure of the delay suffered by projects as a result of the application of a resource allocation priority rule. -Resource utilization ... a measure of the total resource cost (including costs such as the cost of hiring, firing, and maintaining resource inventories) under different allocation rules. -In-process inventory ... a measure of the cost of unfinished work in the system.
Project Buffer
The time between a project's anticipated end date and the due date specified by the customer. According to advocates of critical chain applications, buffers allocated to individual activities are removed and accumulated at the end of the project where they can be shared.
Crash Cost
The cost of adding resources to complete a task in a shorter time frame than its normal duration. Crash Cost / Month = The difference between the normal cost and the crash cost, divided by the difference between the normal time and crash time, based on a specified time unit (days, weeks, months, etc.). Normal Cost = The cost of completing a task at its normal time
The Critical Path
The longest duration path of activities in a network schedule, which determines the anticipated total amount of calendar time a project will consume. Critical Path activities are those activities for which Early Start (ES) = Late Start (LS) and Early Finish (EF) = Late Finish (LF)
If the calender should not dictate reporting frequency, what should?
The need for information should dictate the report frequency. For projects, it is more appropriate to let milestones, scope changes, problems, and the project team's general need for information dictate the timing of reports.
Crashing
The process of analyzing the trade-offs between the fixed costs associated with ongoing project work and the cost of applying additional resources to shorten critical path activities. -trade-offs between prolonging a project (continuing to use more resources / fixed costs) and spending more money to apply extra resources to finish more quickly Crash Time = The least amount of time in which a task can be feasibly completed. Fully Crashed Time = The absolute shortest amount of time in which an activity can be accomplished - typically the most expensive option (not always) Normal Time = The time required to complete a task under normal conditions, typically in the time specified in the initial project schedule, before any crashing has been applied. = usually the least expensive option -There is usually an anticipated loss of efficiency and the need for someone to serve in a coordinating and training role. This is what drives crash costs up. Incremental Crash Cost (Cost of Crashing Per Day) = Crash Cost - Normal Cost / Normal Time - Crash Time Tabular Approach for Project Crashing = A matrix used to display a series of crashing decisions.
Project Scope Reduction
The process of eliminating tasks or deliverables from the work breakdown structure (WBS) with the intention of shortening the duration or cost of the project.
Using Earned Value Analysis, explain how the total cost of a partially completed project can be estimated?
The total cost of a partially completed project can be estimated by dividing the amount spent to date by the estimate of the project's percentage completion. However, in general, this is not an effective way to estimate the cost of a partially completed project. A considerably more accurate approach is apt to be that of summing the costs of completed activities and a knowledgeable guess on the cost incurred on activities underway.
Why can't the Project Manager use the organization's current information system for project monitoring and reporting?
There are two main reasons why the PM can't use the organization's current information system for project monitoring and reporting: -These systems are often set up to report information at certain specific periods (e.g., the end of the month or quarter). The information required to control a project often does not conform to such rigid timetables. -The organization's system is usually structured to deal with the organization's standard divisions, and departments. Projects rarely conform to these boundaries.
Given the fact that a project's resource requirements are clearly spelled out in the project's action plan, why are PMs so concerned with resource allocation?
There can be a variety of reasons why resource allocation is of concern to the PM despite having a properly completed action plan. For example: -The action plan only lists general categories of resource requirements such as engineering, purchasing, marketing, and production. In these cases, the project manager must still arrange to get the specific resources (e.g., personnel) needed. -The action plan may only specify how much of the resource is needed and precedence between the activities relationships, it may not specify exactly when the PM will need these resources. -Although the action plan specifies the amount of a resource needed for a particular project, there may not be a mechanism in use that balances the load of resources across multiple projects. This can lead to conflicts and the creation of bottleneck resources.
Favorable Project Uncertainty
Things not currently within the project team's expectations that have the potential to make the project even better or open doors for valuable opportunities currently outside the scope of the project.
Uncertainty Analysis
Tools and processes used to increase a team's awareness of unknowns that can affect project outcomes, and to address those uncertainties by making adjustments in the project schedule, budget, resource distribution, specifications and other project dimensions. Uncertainty assessment occurs at every stage of project planning and management, but the stage immediately following WBS development offers the best place for a productive formal assessment.
Network Logic
Types of Network Logic = Soft Logic = A sequential relationship between activities that can be arranged in a number of ways, depending on the project manager or team's preferences, resources available or other circumstances Hard Logic = A mandatory sequential relationship in which an activity must absolutely be completed before a successor activity may begin -In creating the initial schedule, adhere to hard logic first to avoid building false dependencies based on initial assumptions about resource availability or other circumstances that later may prove to be incorrect. -With hard logic, the team can use schedule float for noncritical activities to adjust the schedule
Adding Time and Resources Based on Project Uncertainties
Uncertainty analysis increases a team's awareness of unknowns that can affect project outcomes. To address these uncertainties, the team must adjust the project schedule, budget, resource distribution, specifications and other project dimensions. The bottom line on uncertainty assessment is that it is not just an exercise in scenario planning, but an essential input to the WBS, schedule and budget.
Dummy Activity
Used in AOA networks and usually indicated by a dashed line, a dummy activity helps keep the activities in a network true to specified logical dependencies. Without a dummy activity, it is possible the network would either miss an important relationship or depict a false dependency. AON networks, by nature of their structure, do not require dummy activities.
Scope Creep
the inappropriate expansion of a project beyond its mission The tendency for a project to grow beyond the size specified in the initial plan. Team member enthusiasm, idle team members looking for ways to contribute during downtime, unanticipated issues discovered mid-stream, and redefinition or clarification of customer needs are some of the factors that can contribute to scope creep. Scope creep is one of several phenomena that affect project delivery and cause actual performance to depart from planned performance. -Big in software / video games --> also common with Microsoft Operating Systems