PMI CAPM – Plan and Control Project Time Management Part 3
Estimate the Activity Resources The next step is to calculate the activity resources. We have so far identified our scope, decomposed it, and found the activity list; now we’ve already put the activities in order. So the next step is to figure out what resources we’ll need and how much of each we’ll need to complete the various activities. Now, resources are not just people. Now, primarily, that’s what we’ll be using—labor—but also consider equipment, tools, facilities, and any material that you’re going to need in order to complete the…
The next step is to calculate the activity resources. We have so far identified our scope, decomposed it, and found the activity list; now we’ve already put the activities in order. So the next step is to figure out what resources we’ll need and how much of each we’ll need to complete the various activities. Now, resources are not just people. Now, primarily, that’s what we’ll be using—labor—but also consider equipment, tools, facilities, and any material that you’re going to need in order to complete the activities you’ve identified. As a result, estimate activity resources. You have to think about all the characteristics of each activity.
What people, equipment, materials, and facilities are available? Now facilities are things like space that you have to rent or equipment that we’re not really equipped with. We’ve already identified that. But facilities could also be like airports or things of that nature. Estimate your activity resources accordingly. Let’s look at the eDO for this process. The time management Plan our activity. List the attributes of those activities. Resource calendars are a new term; we’ve not talked about them yet. A resource calendar, just like it sounds, identifies when people are going to be available or when resources like a meeting room or pieces of equipment—things of that nature—will be part of the calendar.
The risk register Another new term Well, the risk register is a big listing of all the risk events in your project and the characteristics of those risks. We’ll see more about the risk register coming up in Chapter 11 in the Pinbuck activity cost estimates. What’s the cost? We haven’t done any cost estimating yet. So this is an input, but we want to know how much these resources will cost us. And then enterprise environmental factors, any rules that you have to follow, OPA templates and forms, tools, and techniques Here. Expert judgement is an alternative Senior Engineer junior analysis Engineer alternative analysis with materials and equipment Published estimates This is one you may not be familiar with, and there are no published estimates. It could be software, or it could be an actual guide. But the idea would be, if I am going to, well, let’s just go to a printing company for a while.
Back in my early days, I did a lot of consulting in printing. And one of the things that we could do with this particular printer was print on foil, like the lids of yoghurt or wraps around bottles or things of that nature. Well, they had a little calculator piece of software they could put in this particular printing press with this many colours of ink—four colours plus white because it’s foil. Are they going to coat it with varnish to make it shiny or not? They had all these different combinations they could make. They would put that into this database or this piece of software, and then they would say, “How thick is the foil?” Or material—what type of material are we printing on?
And then they could hit compute, and it would calculate how long it would take to create x amount of yoghurt lids, wraps for bottles, or whatever they were printing. So that’s the published estimate based on these conditions. This is how long it should take based on the humidity and this type of concrete material. This is the time it should take to cure.
So that kind of stuff is published as estimating data because we need to know how long things take to complete based on the materials we’re using. Bottom-up estimating means that we take our scope and break it all the way down to the work packages and the activities list. Then we say how long and how much those activities will take in order to complete them. and then we add that up. Top-down is more of me getting ahead of myself a little bit. But a top-down estimate is like an analogous estimate. Project A took six months. Project B is a little bit bigger.
So we’ll say eight months. So that’s top-down. Bottom-up, top-down is untrustworthy. Bottom line, my point is that it’s much more reliable. We’re starting at the bottom. We’re starting at the actual activity and creating an estimate. And then, of course, project management software can be a tool of technique. In this case, we’ll use Microsoft Project to help us calculate and predict outputs. You’ve determined your activity resource requirements. You might have a resource breakdown structure. It’s much like the work breakdown structure, but instead of deliverables, it shows where resources are utilised in the project.
And then you may have updates to your project documents. A little bit more about the resource calendar The resource calendar helps me see when people or resources are available in a matrix environment, especially since I may have to negotiate for the resources that I need. If they’re not available or I can’t negotiate with another PM, Then I might have to just move that activity so I don’t have a pause in my project unless it’s hard logic and I can’t move it, which is the next point.
I may have to delay that activity from starting or even delay the whole project if the whole project is dependent on this activity to move forward. In some cases, I might have to find alternative resources if I really wanted Bob, this senior engineer, to do these activities. But Bob is like, “Hey, I’m sorry; I’m taking a three-week vacation, which I’ve planned for two years, and I’m going to Hawaii for three weeks.” Not available. I can’t let my project sit for three weeks. So I have to find someone else who can do those activities instead of Bob. As a result, this could cause some issues in my project. But I want to know that as soon as possible.
Activity Resource Needs Well, there are a couple of terms here that we need to be aware of for your exam. The first one is effort-driven activities. Effort-driven activities imply that the more labour we have, the more effort I put into that activity, the faster we can complete tasks. So as an effort-driven activity, we have to pick up all the trash in that football stadium after the game. Well, if one person has to do it, it’s not going to be much fun for that guy, and it’s going to take forever. But if we can get a couple hundred volunteers, we can really knock this thing out quickly.
So effort-driven activity means that the more labour we put into an activity, the faster we can get it done. So think about painting, landscaping, and things like that. We can get that done faster with more labor. Fixed-duration activities: it doesn’t matter how much labour we put into an activity; it’s going to take the same amount of time. I can’t put more and more people on a printing press and expect that printing press to work faster. It could only create a maximum number of pages per hour. I can’t put two network engineers in front of a server to instal it and expect it to be done faster. In fact, like most network engineers, it would probably take longer if two people were there. So fixed-duration activities mean that they’re of fixed duration.
You can’t shorten the duration just because of the nature of the work. Effort can affect the completion date of effort-driven activities. However, we have to consider the law of diminishing returns. The law of diminishing returns basically states that we cannot continue to increase labour and reduce the duration of an activity. So, for example, suppose you have a large cornfield that you need to harvest the ears of corn from. Well, the law of diminishing returns tells us there is a maximum yield. There’s only so much corn we can get out of that cornfield. Adding more labour to go in and harvest the ears of corn doesn’t mean that there’s going to be more corn because more people are working. There’s a maximum yield. There’s only so much corn in there, regardless of how much labour we put into the cornfield. The second thing is the yield. The profitability of going and harvesting that corn is very high. So by adding more and more labor, we could surpass what it’s worth because we have to pay all those people. So there has to be a balance between the yield, what it’s worth, the amount and cost of labor, and what our profit margin is, or the value of completing that task for what we’re taking out of the field.
Now, the next part of the law of diminishing returns is that I can’t continue to add labour to get things done faster; it just won’t work. So I can’t say, “Okay, if I put eight people in there to harvest the corn in this field, to go and pick all those years of corn with eight people, it’s going to take 40 hours, 40 hours per person.” For those eight, I can’t say, “Well, if I add eight more, can I get it done in 20 hours?” What if I add after that? I have 16 people if I add; what if I add 16 more? Can I get it done in 10 hours? So, can I add 64 people? and so on.
But you can’t just keep adding labour to get down to just saying, “Okay, the work is going to take ten minutes.” It wouldn’t be feasible. One guy’s got to walk to the other side of the cornfield to pick that corn. So the law of diminishing returns is something to consider when we add labour to an effort-driven activity. There are many things to consider, but for the most part, there are no effort-driven activities. I can add labour to reduce duration, but there is a limit to how effective that idea is. We’ve talked about the resource calendar. when resources are available. We also have another calendar called the project calendar, and that’s when your project work can take place.
So you can only work Monday through Friday between 8:00 a.m. and 5:00 p.m. That’s a great calendar. More likely, you can be at the job site between seven and three, and that’s when work is allowed to take place Monday through Friday. And these are the company holidays that we’re going to take. Or we have expectations here that we’re going to pause the project because of a busy season or something like that. So the project calendar is when project work is allowed to take place.
Resource calendars are when resources are available. So the project calendar, you might say, shows that we can work between seven in the morning and seven at night, and we’re going to work Monday through Friday as expected. Bob, on the other hand, has them on his resource calendar. Bob’s going to Hawaii for three weeks, so that could interrupt—to be more precise, that one individual could interrupt our project—because even though our project says Monday through Friday, seven to seven, the individual resource is going to be gone for three weeks. So we have to consider the project calendar. but more specifically, the resource calendar.
A term that I introduced a moment ago was the “resource breakdown structure.” According to the work breakdown structure, it resembles a hierarchy or an org chart to some extent. Well, a resource breakdown structure follows that same decomposition, but it shows the utilisation of resources. It helps to expose where I have resource constraints or am lacking in particular resources. So if I look at my resource breakdown structure on top of my WBS, I can see where I have a lot of labour in some areas and where I might be lacking in resource courses and skills in other areas. So it helps to identify that and what resources I need. All right, good job. This lecture taught me a lot and helped me a lot. Keep moving forward.
Our next discussion is how to estimate the activity duration. We want to find out how long each activity will take to complete based on the resources and characteristics of each activity. As a result, the more detail you have available, the more accurate this process of estimating activity duration becomes. This gets us back to that idea of a bottom-up estimate, where I have the activity list and lots of details. Maybe I’ve done this type of work before. So I can be more accurate when I create my estimates. I need my activity list. Of course, that will be a factor here; what resource requirements do you have that may affect the duration? What about the activity attributes?
We’ll talk about that and how that affects duration and resource capabilities. So senior engineer versus junior engineer Or you might think about pieces of equipment that are larger and may operate faster than smaller ones. And then what OPAS do you have available as you begin to estimate activities? Our edo is here. For estimating activity duration, we need the schedule management plan, the activity list, the attributes of each activity, the resource requirements, resource calendars, the project scope statement, the risk register, and that resource breakdown structure that we talked about in the last lecture, enterprise, environmental factors, and OPA. Now, tools and techniques are here, and we’re going to talk about all of these in detail in this section. So expert judgment, analogous estimating, parametric estimating, and three-point estimating We’re going to look at all of that in detail and then group decision-making techniques. And a new idea here is reserve analysis, and we’ll talk a little bit about that coming up, along with outputs, activity duration estimates, and project document updates.
Let’s talk about some of these estimating types. I’ve already hinted at some analogous estimating for the first one. It creates an analogy. So we say, well, that these activities in a previous project took about four weeks to get done. So it’s a little more work in this project. So I’m going to say it takes about six weeks to get done, or Project A took six months to complete. Project B is a little bit bigger. I’m going to guess it takes eight months. As a result, it must be similar project work. So I have to have historical information and similar projects. And this is also known as “top-down” estimating. It’s not always very reliable for a number of reasons. One, analogies aren’t always a one-to-one correspondence. Two, if that initial project that you’re basing your current estimates on is flawed because the project manager didn’t have accurate records of how long activities actually took to complete, that’s going to affect your estimate over here because you’re basing it on outdated or incorrect information.
We also may not know how long activities take to complete because we may not be using the exact same resources. So analogous estimating is quick; it’s top-down, but it’s not very reliable. Parametric estimating is where we have a parameter for estimating. So, for example, every time we instal a garage door, we know it takes 6 hours to do, or whenever we have 1000 light fixtures to instal in this project, they take about an hour each. So that’s 1000 hours to instal all of these. So I have some parameters to create an estimate. It’s ideal for repetitive work where I’m doing the same types of tasks over and over again, like installing 1000 light fixtures. The problem with parametric estimating is that it does not consider the learning curve. Here’s the idea. Let’s take those 1000 light units that we said we’d go out and get five or six of to see how long it takes to install. And the guys go up, and they’re installing those light fixtures. And it does take them about an hour for each one. The problem is they’ve never done that type of work before.
They’ve never worked with these particular light fixtures before. So they’re having to learn how to instal that light fixture as they’re going through and doing the project work. So over time, they’re going to get more efficient because they’re doing the same task over and over and over.So they have this idea of the learning curve—that they are taking this dip in efficiency. But over time, they will become more efficient at installing that fixture. So you know what it’s like the first time you try to do any new activity. It might take you a little bit longer. It feels awkward. You don’t exactly know how all the pieces fit together. But then, over time, you get the hang of it, especially if you’re doing that over and over and over. So that’s the learning curve. The learning curve is basically that we become more efficient by repeating the same activities. But just because we’re more efficient does not necessitate that we will become more productive. If the guy installing the light fixture knows that you believe it takes an hour to instal the light fixture, he will do so. They might get the light fixture done in 20 minutes and then take a 40-minute coffee break. You don’t really know. As a result, we must be aware of the fact that parametric estimating has flaws, one of which is the learning curve. A three-point estimate is just an average.
However, it’s kind of a pain to do because for each activity you have to find the optimistic, most likely, and pessimistic estimates. And then you find the average of those. It’s also called “triangular distribution” because they’re creating a triangle. Optimistic or pessimistic, most likely. And there’s the formula: you take optimistic plus most likely plus pessimistic and divide by three. And that will be your estimate for that individual activity. So here’s an example: We say our optimistic estimate is 25. Our most likely time is 45 hours. Our pessimistic time estimate is 75 hours. So we add that up, divide by three, and get our average, our three-point estimate. This will take 48.33 hours. So that’s what we think it’s going to take based on our average here. A similar estimate is called pert. “Pert” means programme evaluation and review technique. And PERT is also called beta distribution. The three points were triangular, so beta is more of that big curve that we see. It’s a little bit different. What PERT does is still use optimistic, most likely, and pessimistic language, but it’s weighted towards most likely. So it’s optimistic plus four times the most likely plus pessimistic divided by six. It’s divided by six because there are six factors: optimistic, four most likely outcomes, and one pessimistic. So let’s take those same numbers from our triangular distribution and look at them here. For beta. So 25 was our most likely plus four times our most optimistic. Four times 45 plus 75 divided by six This would be 46.66 hours with daylight. I’m going to hop back on the slide. Remember, we did this just a moment ago.
Well, I’m not going to hop back on a slide. It would be 43 hours, which is what we had estimated before. It’s now 46 hours. I just wanted to show that it’s skewed toward the most likely outcome, as it usually is. So for your exam, you’ll need to know both of these, and you’ll likely be called upon to do a calculation using PERT or, most likely, by doing both. I’m sorry, I’m doing the average, the three-point estimate. Three-point estimates are just an average of four times the most likely. That’s the big difference. Reserve Time reserve time is where we take up to 15% of the project duration and set that aside for when activities come in late. The idea is that we don’t pad each activity’s time. If we have 100 activities in a project that each take between 8 and, say, 40 hours, we could say, “Oh, instead of 8 hours, I’m going to give each of them 2 hours per eight hours.” So that would mean that for an eight-hour activity, we would actually say it could take up to 10 hours. That would be an additional ten hours on a 40-hour activity.
So that could take 50 hours. If we pad all of our activities like that, trying to accommodate for overages in time or mistakes or defects, we’re adding a tonne of time to our project. That also drives up costs because we’re paying for that labor. We want very accurate estimates of the most likely time for each activity, with no padding. And then we’ll say that for our whole project, it’s going to take six months. So that would be about 180 days. So we’ll take 10% on top of that. So we’ll take about 20 extra days and add them to the project duration. So instead of 180 days, We say 200 days if activities come in late. If they come in late, then we pull that out of this pool, this reserve time, at the end of our project. So it is a buffer, but it’s at the very end. So the buffer isn’t assigned to each individual activity. And there are a couple of reasons why this is a better thing to do. The first is the point you see here, called Parkinson’s Law. Parkinson’s Law states that work will expand to fill the time allotted to it. If I tell you this activity will take 10 hours, it will take 10 hours. If I get done early, I’m not telling you because you might expect me to do that every time.
So if I say it takes 10 hours, it will magically take 10 hours. Or, I know it’s probably only going to take 8 hours, but for the first 2 hours, I browse the web and read the newspaper and take my time, or throughout the day. I start at hour two, and I hope that nothing goes wrong. And oh, if something does go wrong, now I am late for the activity. So there are all sorts of problems with padding each activity or allowing that to happen. Over time, we can create some trends and historical information about how long activities should take. So initially, you may not know if someone is padding activities or not, but you have to watch that in your project. And we gradually learn that our activities are padded. We can begin to predict how long activities should take if we instead say this is the most likely duration, so people can give an honest estimate, or if we have a history of how long these things take over time. And that allows our projects to finish in a more reasonable amount of time based on activity duration. It also helps that as those activities are done, if we say it’s going to take 8 hours and it gets done in 8 hours, it allows the next activity to begin faster rather than having to wait for that buffer that’s been padded for each individual activity. So reserve time is about 10% to 15% of the project duration, and it’s allowed for activities that truly run over their project duration estimate. Okay, good job. Moving forward, there is a lot of really good, important information in this lecture.
SY0-501 Section 1.1- Implement security configuration parameters on network devices and other technologies.