How many legs does a dog have if you call the tail a leg? Four. Calling a tail a leg doesn't make it a leg - Abraham Lincoln
The notion that we can rename things and then assume they are the same doesn't work, just like Lincoln said. The notion of measuring progress with the passage of time and calling it Earned Value, doesn't mean we're doing Earned Value.
Doing Agile without doing Scrum, XP, Crystal, or DSDM is not doing agile.
The LinkedIn forum The Project Manager Network - #1 Group for Project Managers which I sometimes wonder if that is actually the case, has a conversation going on around project failure. A Master's student asked about project failure modes. That led to the use of Earned Value. One participants made some pretty boneheaded statement around EV:
(EV) It's a tool and anyone who thinks it is an actual depiction of real progress is fooling themselves.
Percent complete, unless 100%, is at best an educated guess.
I've heard of the 0/100 and the 0/50/100 methodologies. I disagree with the 0/100. If you are trying to accurately portray progress, it is best to develop a set of standard credits, for example when doing drawings or, actual measurement such as in construction. Each activity has a value from which percent complete can be derived.
An equipment general arrangement drawing is a good example (percentages shown are individual contributions) - using 40 hrs/drawing as the allowance (we get)...
5% (2 hrs)for applying the border and title 20% (8 hrs) for defining the area - boundaries and overall dimensions 30% (12 hrs) for showing all the equipment 5% (2 hrs) for the drawing being checked 10% (4 hrs) for it being Issued for Approval 15% (6 hrs) for it being Issued for Bid 15% (6 hrs) for it being Issued for Construction. 100% = 40 hrs.
So, silly me, I responded that determining physical percent complete was a straight forward process once you have Quantifiable Backup Data or measures of Physical Percent Complete, or even better, Technical Performance Measures. Let's look at each concept
EV, when percent complete is measured in tangible units of physical percent complete is a depiction of real progress. Why because the progress is physical percent complete. It's a tautology.
Percent complete is NOT an educated guess, it is tangible proof. This is call Quantifiable Backup Data. Bring the number of drawings to the table you said you were going to do on the day you said you were going to do them, and you'll get the prorated share of the earned value for the total drawing package. Bring 8 of the planned 10 on the day you planned to produce 8 and you'll get 80% of the total work package for producing 10 drawings.
0/100 is best, all others skew the performance. The last piece of that concept is actually correct. For a 10 drawing package, with each drawing weighted the same, that is 10%, 5 drawings, completed on the planned day, gets you 50% physical percent complete.
No we go straight into the ditch. Progress is NEVER measured with the passage of time except in Level of Effort work. The actual costs (ACWP) is interesting to cost accounting, but it tells us nothing about the progress of the project except how much money we have spent compared to our budget. If the assigned (apportioned) value were all there was, then OK. But the conversation included the number of hours, and there where the problem starts.
Then the final come back from the OP.
If you're doing a drawing and it takes 40 hours to do the drawing and no two drawings are alike, how do you determine what percentage complete you are? When estimates of the work to be completed are put together, they will estimate X drawings at 40 hrs/drawing. They will have different standards by discipline. Will a person ever report 41% complete on a drawing? Most likely not. It will be shown as 40%. Collectively all the drawings may be 41%, but not individual. No matter how you look at it, it is still an estimate.
First measuring progress to plan by the number of hours consumed is called Level of Effort. Second LOE is a very poor measure of anything other than the passage of time and consumption of resources.
In the end the poster was insistent that ANSI-748-B is just a guide, and doing EV was a local issue. No doubt that is true in his domain. But as a practitioner of EVM using ANSI-748-B for programs subject to DCMA Validation, as well as engagements with the DOD office that own the Earned Value Management processes for the DOD, I'd be laughed out of the room with an approach like that.
Using the WBS define the Work Packages that produce the deliverables for the program
Assign an Earned Value Technique to each of these Work Packages - 0/100 for the individual tasks inside the Work Package is the absolute best. You're either done with the task or you are not. Weight the tasks if you want, but sum up the "done ones" and compare that to the total work and compute a percent complete.
Sequence these Work Packages in an Integrated Master Schedule
Assign budget (BCWS) to each of the Work Packages
Collect the actual costs to perform the work (ACWP)
Compute the Earned Value (BCWP) using a simple formula BCWP = BCWS x Physical Percent Complete.
Compute Cost and Schedule variance. Make management decisions based on these and take corrective actions to get back to GREEN.
Repeat step 5, 6, and 7 every month at a minimum, more often if possible.
That's all there is - essentially - for doing Earned Value Management. Of course if you read ANSI-748-B, the NDIA Earned Value Management Intent Guide, and the DCMA Intent Guide, there is a lot more.
You Can't Make Stuff Up
OK, you can. But if you do, it makes having a conversation about EV much harder.
The conversation on Twitter around No Estimates #NoEstimates brings a smile. Here's some samples
Marketing needs a rough idea of when alpha-level code will be available. Allowing a few weeks for alpha testing and a few more for beta testing provides a time line. That may well be good enough.
That's called an estimate. A rough estimate for sure, but it's an estimate
From the same blog (a good one BTW)...
We're on an enterprise system now and management needs to know how long and how much cost it will take to get to a Minimal Viable Product. The first release has to be functionally complete in order to be competitive. Everyone understands that this effort will take several months to get to beta-level code. Management needs some idea of what they’re getting into, how long it will take, and how much it will cost.
Now we're into the realm of actual estimating
Are No Estimates Better Than Estimates?
Before answering this another question needs to be answered...
What is the value at risk?
This means how much money and time are you willing to risk without understanding how much time and money is at risk.
So before anyone can answer the question about estimating value, that question needs to be answered by the owner of the money. NOT to consumer of the money.
This at risk question rarely comes up in the agile world. It doesn't come up enough in our formal FAR/DFARS acquisition work either. The at risk question is a risk management question. Agile claims to be a risk management process - which of course is laughable in our DOD/NASA/NRC/FDA/NNSA risk management world. All software intensive by the way.
So before venturing further, what's the value at risk must be answered. Then the owner of that risk, can tell those who should be working in the best interest of the owner of the risk, if an estimate is needed. Not the other way aorund.
Without this answer, the discussion on #NoEstimate is just sharing of personal opinions in the absence of any value at risk.
There is a twitter discussion going on around Neil's post of People Need Estimates. This is a typical agile approach. No real domain or context, just a principle looking for a problem to solve.
First let's establish some ground rules:
I'm a strong advocate of agile development. I work prorgams that use agile. Big programs. Billion dollar programs.
When we are spending other people's money it's not about "us" and our favorite method of spending that money. It's about governance. Don't like governance, then don't work on projects that spend other peoples money.
And the final one ...
Agile - in many cases - is spending people's money to discover the requirements. That's fine. But acknowledge it. Requirements emerge. Requirements change. Requirement are wrong many times. But don't say it'll be OK to use agile and ignore that you're spending - maybe even wasting - other people's money and calling it progress.
Neil says "People need certainty about what they will get and how much they have to spend. " This is not factually true in many domains, not is it actually possible. Those with the money need to know the confidence in the spend plan and the project duration. Certainty is not possible. But don't use that as an excuse for not having a confidence interval estimate:
We will complete this project on or before the 3rd week in November, 2014 with an 80% confidence and a 12% error band on that confidence. This is easily developed and is done every month on the programs we work.
We will complete this project at $1.6M or less with 80% confidence and a 10% error on that confidence.
This is what those spending the money need to know. Otherwise the project is Level of Effort. Work producing good things till the money runs out, get some more money continue doing good things. No problem. That is called maintenance. This is how PayPal uses Scrum. They budget annually for features, develop those features within that budget, repeat forever.
I love the notion "When estimating a date or cost you are creating uncertainty around those things, because you are guessing. "
Well stop guessing. Start being a software professional and start estimating. Have you done this before? How long did it take. Has anyone you know done it before? Go ask them. Guessing is lame. No estimates is even lamer. Worse, it's just being lazy.
One last thing, "People still need 500-page business requirement documents." This is bogus. We work multi billion programs, with 100's of millions of dollars of embedded sofwtare and don't have 500 page requirements documents. Nonsense.
If you don't know where you are going, if you don't have some notion of what done looks like, if you can't tell me approximately how much and how long, please don't start. You can be a binary search process for duration and cost for any tangible piece of software and within five question get without 20%. That's good enough to start. So start and take corrective actions with ne estimate along the way.
Finally "However, I would argue that #NoEstimates gives greater certainty than estimating does." There is absolutely no evidence for this. This is pure speculation and therefore also nonsense. Think about it,
A builder comes to your house for a kitchen remodel.
You tell him roughly what you want done.
You ask "how much will this cost, approximately?"
"Oh I don't know, we're not good at making estimates, let's just get started and see where this takes us."
Are you out of your !@#$'ing mind. It is no different for software. Here's a nice short intro from Target Process, that actually makes sense.
Let's say the CIO comes and says "I need these features", and asks "how much and how long?" You say "Oh we get better outcomes when we don't estimates." Really, and some one believes that nonsense? I guess so.
When the role of the project manager is to push the rock up the hill and then let it roll down again, there is little chance of success, and in the end little need for project management or the project manager. Cancel the project, everyone just go home.
Risk Management is how adults management projects - Tim Lister
There have several rounds of how to use analogies and how not to use analogies in the past few years.
These involved notions like agile is an untended garden. Actually and untended garden and called a weed patch.
Or we can't really stop and develop a strategy, because we're always putting out fires. Actually firemen rarely put out fires. They spend the majority of their time preventing fire with fire safety, inspections, fire inspections. Their job is to never have fires start.
And of course for false analogies of the double pendulumas a stand in for chaos and unpredictability. Since the equations of motion are easily defined - an exercise for any upper division physics student - and a MathLab plugin, you can plot the path of the double pendulum.
And my favorite the attractor analogy, in which it is presumed that some how in chaos theory the attractor attracts. Without understanding that those pretty pictures of the attractor are the result of the underlying equations for the system.
So with that in mind, there is a new book from one of my favorite authors, Douglas Hofstadter, Surfaces and Essences. In the book Hofstadter makes the case for analogy as the fuel for creative thinking. Using Robert Oppenheimer's quote...
whether or not we talk about discovery or of invention, analogy is inevitable in human thought, because we come to new things in science with what equipment we have, which is how we have learned to think, and above all how we learned to think about the relatedness of things.
But as always we need to take care to assure that those analogies we use to expand the conversation, don't violate the laws of physics, gardening, or mathematics.
Several core concepts get confused. So before taking any deep dive into "managing risk," these need to be established.
What is Risk
There are many definitions of risk from a variety of sources. In the end these definitions are all pretty much the same.
Risk involves the probability of something happening in the future.
When that something happens it impacts the project in ways that are not good.
There can be a probability of the effect of the impact as well.
Handling the risk means knowing what kind of risk it is, and what the choices are for handling the risk.
Here's a good definition that can be used in probably any domain.
Risk refers to the uncertainty that surrounds
future events and outcomes. It is the expression
of the likelihood (probability of occurrence) and (probability of) impact of an event with the
potential to influence the achievement of an organization’s objectives. - Managing Risk in Government: An Introduction to Enterprise Risk Management, IBM Center for The Business of Government.
I've edited this a bit to remove the likelihood measure and replace it with the probability just to keep the math straight. You'll see why below when it comes to ordinal values in the risk matrix - a bad idea.
There is a time honored approach to ranking a risk, by calculating some number. This number is meanigless of course, because it has no scale, it is just a ordinalnumber. We need cardinal numbers for actual risk management.
Risk = Probability of Occurrence x Impact
This is a trick question. The risk matrix approach that results from this calculation treats these numbers as likelihood not probabilities. But in fact they are probabilities. As well they are Ordinal numbers (1, 2, 3, 4, 5 usually) and as such represents the relative ranking of the likelihood of occurrence, not the actual probability of occurrence.
This approach starts with a major problem - a show stopper problem. The two values on either side of the multiplication sign are probability distributions, not real numbers. There is no MULTIPLY operator between two probability distributions. The is the CONVOLUTION operator, but that is not likely to be of much value to ordinary project management staff. One starting point for a better understanding of the problems with the risk multiplier and risk matrix approach is the work of Tony Cox. Optimal Design of Qualitative
Risk Matrices to Classify
Quantitative Risks. Tony's source paper provides the basis for this discussion, "What's Wrong with Risk Matricies."
In this link, it is stated again, so I'll restate it here
It is a category mistake to multipy ordinal numbers
By category error it means the objects, the categories, do not have the proper properties to work with the operators. For some more discussion of this topic and a bit of counter discussion, see What's Right with Risk Matricies.
Where does risk come from?
Risk comes from uncertainty. There are two kinds of uncertainty.
Uncertainty that can be reduced - reducible uncertainty. This is called epistemic uncertainty. This uncertainty is characterized by the lack of knowledge. We can buy this knowledge.
Uncertainty that cannot be reduced - irreducaable uncertainty. This is called aleatory uncertainty. This uncertainty is an inherent variability in the project processes and characterized by a probability distribution. We can not buy more information about this uncertainty.
The critical point here is the reducibility and the irreducibility of these uncertainties.
If the uncertainty is irreducible, then only margin can be used to protect the project from the risk. This is scehdule margin, cost margin, techncial performance margin.
If the uncertainty is reducible, then we can buy down the uncertainty and therefore buy down the risk. That is we can spend more to find out more information - increase our knowledge. This is done in one of two ways:
Spend money in the project to increase our knowledge.
Provide a Management Reserve or Contingency to handle the risk when it comes true.
How is Risk Maanged?
We must start with a risk management process. There are several, but they are essentially the same. Here's my favorite, there are others of course, but this one covers all the steps.
So What's the Point Here?
There is no need to make up definitions for risk and risk management. There are plenty around and all of them are in use on actual projects by actual project and program managers, managing risks every day. Providing your own definitions, is sporty at best. At worst, it shows you haven't done your homework.
Uncertainty is the source of risk. There are two types of uncertainty - reducible, epistemic and irreducible, aleatory. If you do not separate these two, you cannot credibly have a risk handling plan. If you do not have a credible handling plan, then you're not actually managing risk.
Ordinal numbers cannot be used to make risk decisions. Cardinal numbers are needed. No ranking likelihood of occurrence as 1,2,3,4,5. Not allowed, it's bogus. Same for impact. Bogus. And certainly no multiplying those two, even more bogus.
Risk Management is How Adults Manage Projects - Tim Lister
Chapter 1 of Maximizing Project Value introduced the idea of value. Chapter 2 speaks to where and how that value flows. A couple years ago there was confusion about the term value. Let's restate it here again. The value John speaks to is the business value. He speaks to Earned Value later in this book, but even more so in Project Management the Agile Way.
Chapter 2 Highlights
There is a distinction between project value and business value - project value is measured by Earned Value - how much of your budget did you earn? Business value must be derived from the business strategy. A business case if fine but a measurable strategy is better. Balanced Scorecard is the best way to connect business value with Earned Value. Here's how to do that Notes on Balanced Scorecard.
Interests of the customer must be balanced as the value is developed - one way to do that is with a Scorecard that connects project performance with strategy. Then the customer can see the Measures of Effectiveness (MoE) of the project's outcomes against the fulfillment of the strategy.
Projects are the instrument of strategy - yep this is how strategy gets implemented. The literature shows strategies fail most often during execution.
There is a six steps process from opportunity to projects. Projects drive value - I prefer the Goal Question Measurement approach to making these connections. John's approach is straight forward and simple.
I've found what I was looking for in Chapter 7 that makes the book critical to our success - connecting Business Value with Capabilities Based Planning. I won't skip ahead. For now Chapter 2, is the starting point for putting these ideas to work.
Cost estimating methods have been around for a long time. The current processes found in agile use a points system, sometimes a Fibonacci series to bin the values of the points.
The challenge with this approach is the estimate in agile is not monetized so we can't really tell if the Total Allocated Budget (TAB) is sufficient for the project at any point in time, unless the capacity for and the quality of the ourcomes is steady - that is Level of Effort.
With the LOE approach, the capacity for work is the critical measurement needed for estimating the cost at completion. As well continuous updating of this capacity for work is needed and correctly done on good agile projects.
But there are other issues with this LOE approach on larger projects:
Do we know the variances in the capacity for work and how those variances will impact the final Cost at Completion?
Do we know the interdependencies between the various work products and how they impact the final cost?
Do we know the Aleatory uncertainty - the natural occurrence that can't be fixed and has to have margin.
Do we know the Epistemic uncertainty - the event based risks that need a risk handling plan?
So the examples like that found at Projects @ Work, don't really consider any of the underlying uncertainties in estimating. Without the next level down - statistically adjusted estimates of the work effort, the capacity for work, the quality of that work, and the interdependencies between those work activities and their products, the simple and maybe even simple minded approaches to estimating have limits to scaling.
This is one of those topics where everyone is right in some way, depending on the domain, context in the domain, and scale of that domain. As agile enters the larger acquisition community, where we're spending other peoples money - maybe 100's of millions of dollars, care needs to be taken when applying un-monetized, non-probabilistic, non-joint probability (cross correlations between work element) and non-stochastic forecasting models. The real world is not that simple.
Over the past weeks there have been several discussions on the forums and Blogs amount risk and risk management. Here's a short post on those topics and their impact on project performance.
Risk Comes from Uncertainty
Risk does not exist by itself. Risk is created when there is uncertainty. If I am certain that it is going to rain this afternoon, then there is no risk of rain. It's going to rain with 100% probability. There is no uncertainty about the forecast of rain.
So first we need uncertainty to have a risk. But there are two classes of uncertainty:
Aleatory uncertainty - is uncertainty that comes from a random process. Flipping a coin and predicting either HEADS or TAILS is aleatory uncertainty. In other words, the uncertainty we are observing is random, it is part of the natural processes of what we are observing.
Aleatory uncertainty refers to the inherent uncertainty due to the probabilistic variability.
This type of uncertainty is Irreducible, in that there will always be variability in the underlying variables.
These uncertainties are characterized by a probability distribution.
The parameter that is being measured - duration, RPM, discharge from a river flow, is stochastic and cannot be reduced.
Epistemic uncertainty - is uncertainty that comes from the lack of knowledge. This lack of knowledge comes from many sources. Inadequate understanding of the underlying processes, incomplete knowledge of the phenomena, or imprecise evaluation of the related characteristics are common sources of epistemic uncertainty. In other words we don't know how this thing works so there is uncertainty about its operation.
Epistemic uncertainty refers to limited knowledge we may have about
the system (modeled or real). This type of uncertainty is reducible.
If we have
more information, we can take more measurements, conduct more tests, "buy" more information. This type of uncertainty
can be reduced.
The parameter being measures is usually a characteristic of the material or the physical process. The uncertainty is related to the "lack of knowledge," about this parameter.
Handling Risks Created from Uncertainty
Aleatory risk is not a lack of information. It is a naturally occurring process. We cannot buy more information, so we have to provide margin for this type of risk. Schedule Margin to cover the naturally occurring variances in how long it takes to do the work. Cost Margin to cover the naturally occurring variances in the price of something we are consuming in our project.
Aleatory uncertainty and the resulting risk is modeled with a Probability Distribution Function. This PDF describes all the possible values the process can take and the probability of each value. For a single toss of a coin, there is a 50% probability it will be either heads or tails. For multiple tosses of a fair coin the probability distribution of the total number of heads or the total number of tails is a binomial distribution that looks like this for the numbers of HEADs from fair coin being tossed 20 times.
The PDF for the possible durations for the work in the project can be determined in several ways. It turns out we can buy knowledge about aleatory uncertainty through Reference Class Forecasting and past performance modeling. This new information then allows us to update - adjust - our past performance on similar work will provide information about our future performance. But the underlying processes is still random, and our new information simply created a new aleatory uncertainty PDF.
Epistemic risk comes from the lack of knowledge. Epistemology is the branch of philosophy concerned with the nature and scope of knowledge. Lack of knowledge is epistemic uncertainty.
Epistemic risk is modeled by defining the probability that the risk will occur, the time frame in which that probability is active, and the probability of an impact or consequence from the risk when it does occur.
Risk statements are used to define and model these event based risk:
IF-THEN - says if we miss our next milestone then project will fail to achieve its business value during the next quarter.
CONDITION-CONCERN - our subcontractor has not provided enough information for us to status the schedule, and our concern is the schedule is slipping and we don't know it.
CONDITION-EVENT-CONSEQUENCE - our status shows there are some tasks behind schedule, so we could miss our milestone, and the project will fail to achieve its business value in the next quarter.
For these types of risks we can have an explicit or an implicit risk handling plan. I use the work handling with special purpose. We handle risks in a variety of ways. Mitigation is one of those ways. But the risk handling work is actual work. It is in the schedule. We are doing work to mitigate the risk. We are buying down the risk, or we are retiring the risk. In all cases, we are spending money, and consuming time to reduce the probability that the risk will occur. Or we could be spending money and consuming time to reduce the impact of the risk when it does occur. In both cases we are taking action to address the risk.
The second approach to handling an epistemic risk is the have Management Reserve to cover the cost of the consequences when the risk occurs. Sometimes the term contingency is used. Both Management Reserve and Contingency may be used together. In both cases, money is set aside to handle the risk. We also need time as well, so we may have schedule reserve. But this gets confused many times with schedule margin, but it is still needed.
Risk Management is how Adults Manage Projects
One of the posters stated what would be considered a Lame response to the processes and seeming conplexity of managing risks on non-trivial projects, by stating you're making this to complex - Just Do It. It was lame. Here's the response to those who objective in what ever way to doing risk management.
First answer the question what is the value at risk for your project? Don't know? Go find out. Then ask the project sponsor or the person giving you money to manage the project, if they would be willing to lose that money outright. Just write it off when the risk comes true. Probably not would be the answer. So go do the risk management process.
Here's Tim Lister's advice. The section title is Lister's quote and should be used every time some lame response comes back about risk management.
John Goodpasture sent me his new book Maximizing Project Value, Management Concepts, 2013. I promised John I'd review the book. I started to write a simple review, but then I started marking up my copy and learning and use new ideas. So here's my new approach. I'll post a talking points review of each Chapter across the next few weeks. This is more than a book review. It is a cliff notes for the book.
Chapter 1 - Understanding the Value of Projects
The project's value is the worth of a project's throughput, or the difference in business value measured before and after a project, as earned during the course of the project schedule.
Managing the tension between business and the project is optimizing project success in the context of business success.
The object of risk management and optimization is to effect the best overall outcome as valued by the business. This is an important concept.
Project managers are leaders as well as managers - this should end the discussion about if PM is management or leadership. Both, everyone back to work.
The value earned is planned as the project's budget. This is the simplest definition of Earned Value.
Here's my counter.
There are Principles, Practices, and Processes that are immutable for all projects in all domains for all "methods" of managing the project. That's why they are called Immutable.
No doubt the BoK's have gone off track when seen as "prescriptive" for working projects. But the basis of knowledge needed for success is still there in the Principle, Practices, and Process. A test of this approach is similar to the 12 principles of the Agile Manifesto.
The agile manifesto created a new movement in software development, but lost its way when there were no underlying principles.
PM BoK's have lost their way because they don't start with Immutable principles, practices, and processes. They start - both APM and PMI - with prescriptive knowledge areas and process groups which get confused with methods.
I would conjecture that the 5 PPP's have a matching document in the OGC P3M3 which was used in the UK for some time. It is a maturity assessment vehicle, but starts with core principles. None of the BoK's to date start with "core principles," in the way Plato did with "what is a chair."
When I encounter a "subject matter expert," I've now learned to assess if this person is a "knowledge holder," or a "learning individual." This is what informed that "learning." This came to my from a friend and neighbor who is a graduate of the University of Chicago in economics and spoke at this conference.
In our business - project and program management - there are lots of "knowledge" providers, assessors of knowledge, frameworks for measuring our knowledge. What is needed now is how to learn to make better decisions about our projects. This is not going to happen without a decision making framework for the core principles, practices, and processes for project management. The current Bodies of Knowledge, self-proclaimed providers of better BOKs and assessment tools, authors (I'm one of them), and experts in the field, all need to reassess what we are doing to increase the Learning abilities, beyond the just the possesion of knowledge and the dispensing of this knowledge to others.
How can we actually learn to improve our probability of succes. The Decision Scientist for project success - as suggested here - needs to have art, science, and the scale to provide actionable information for the decision makers for the project.
We have most of the data we need, what we don't do is make decisions on this data, or even know how to make decisions with this data. We report it, but don't use it to make decisions. Numbers matter, but leadership needs to use the numbers.
Forecasting involves making projections about future performance on the basis of historical and current data.
The chart below is a synthetic (same as fake) Cost Performance Index at the program level 2½ years. The area on the right is the forecast of possible values of the CPI given the historical behaviour, with tuning parameters and smoothing functions.
The next step is to use real program performance data over some realistic period of time - say 4 year - and use H-W (or a similar forecasting tool), to confirm that a less that complete assessment, say take 2 years of data, forecast a 6 month value, and see of the actual 2 year, 6 month value come out close the to the forecast.
This is all done in R, with very simple commands, once the time series for the CPI is formatted and partitioned properly.
There's a tremendous popular fallacy which holds that significant research can be carried out by trying things. Actually it is easy to show that in general no significant problem can be solved empirically, except for accidents so rare as to be statistically unimportant. One of my jests is to say that we work empirically — we use bull's eye empiricism. We try everything, but we try the right thing first!
Edwin Land - The Journal of Imaging Science and Technology, Vol. 37, No. 3 (1992), p. 537
The notion that the architecture will emerge, that requirements appear as we go along spending other peoples money, and the customer knows the right solution when they see it, is just that "notional."
Without some agreed upon description of what Capabilities are to be provided by the system, you'll just be spending time and money to find out you don't know what DONE looks like.
The discipline of project management adheres to the dominant model of the project life cycle, or the phased stage-gate approach, of executing projects. This implies a clear definition of mission and system at the outset (to reduce uncertainty), and subsequent execution in phases with decision gates. This approach contrasts with the way the seminal projects were conducted that are credited with establishing the foundation of the discipline in the 1950s. These projects started with missions that were beyond the currently possible, thus any solutions had to emerge over time. They succeeded by a combination of parallel trials (from which the best would then be selected) and trial-and-error iteration (allowing for the modification of solutions pursued over a period of time). Although the success of these approaches was documented and explained by scientific work in the 1950s, today they seem to fly in the face of accepted professional standards, making managers uncomfortable when they encounter them. The explanation for this contradiction has its roots in the 1960s, when the so-called McNamara revolution at the Department of Defense gave a control orientation to the PM discipline. This shift was cemented by the encoded practices of the DoD and NASA, contemporary scientific writing, and the foundation of the Project Management Institute as a professional organization that translated the standard into the educational norm for a generation of project managers. The project management discipline was thus relegated to a "grunt work niche" - the engineering execution of moderately novel projects with a clear mission. As a result, it has been prevented from taking center stage in the crucial strategic change initiatives facing many organizations today. This article describes the historical events at the origin of PM's reorientation, arguing that the discipline should be broadened in order to create greater value for organizations whose portfolios include push-the-envelope projects.
Agile may ne making a come back in project management, but the contracting aspects of large programs needs to deal with the uncertainties as well as the developers.
Terminology that belongs to one knowledge system is often misunderstood by people who work with other knowledge systems. Overcoming linguistic barriers between systems is essential.
As well, there is a flap over the use of Excel for modeling
econometric processes. Which was addressed more in the NPR segment. More on Excel
and modeling later.
In the original paper -
which has now been updated, there are several key words that
trigger red flags in any credible statistical analysis of dynamic
systems like the economy or complex programs. There is an assessment of the
original paper. Let's start with the response to the original paper
from the original authors addressed to the author of the critique.
This
brings us to the core conceptual issue, which Herndon, Ash and Pollin argue
greatly biases our results. They argue that we (they) use an “unconventional weighting
of summary statistics.” In particular, for each bucket, we (they) take average growth
rates for each country and then take an average of the result.
Averages
without variances are not very useful. We all know the story of measuring the most
likely temperature in two locations Cody Wyoming and Trinidad-Tobago and
the misrepresentation of Averages.
Since
economies and projects are driven by stochastic processes,
we must model their data as random.
Everyone
claiming to forecast the future or make correlations between random
processes must have on their shelf and have demonstrated to have
read How to Lie with Statistics,
Darrell Huff.
So ignoring for the moment the very naive statement by two Harvard
professors of averaging the averages in the absence of the variances, and then
making projections of the correlations, there are other problems.
Using
Excel for modeling can certainly be done, but there are much
better ways to model statistical and probabilistic processes - R for one. MathLab is
another.
Excel
also suffers from the in auditability problem. If you build
a spreadsheet and send it to me to make management decisions, I have to look at every cell to determine the right
formula, right range for that formula, and right data is in the right rows
and columns for that formula to work. A pain in the ass for simple
spreadsheets. A nightmare for larger ones. This is simply bad
modeling. Especially since R is free and an academic version of MathLab or Mathematica is
under $300. Come on Harvard professors, earn your reputation.
So What Does This Mean for Project Performance Analysis?
There are pictures in the links above to show that projects are
statistical processes. So here's the bottom line:
All
numbers in projects and econometric models are random numbers.
Correlations
between the source of these numbers may also be random or at least
changing over time - nonstationary stochastic processes.
Models
that don't consider this information are probably not that useful and may
actually - and I'll be crass here - BOGUS.
If
we are ever to produce credible models of how projects work - cost, schedule, risk, and technical performance models - they must be credible
statistical models. That means averages and averages
of averages are simply not allowed without the variances and
even higher order moments and the correlations between the generating functions of
these random variables.
So however, this turns out with the Bad Math people
at Harvard, we've got to do better.
The
current Earned Value Management processes don't consider the statistical
nature of the performance indices. This is bad. Here's a simple and very understandable paper "Performing Statistical Analysis on Earned Value Data."
As
well, the calculations of future performance use cumulative numbers
which wipe out the varainces, the current period which is a point sample
to compute the Estimate At Completion. This is not only bad it is naive
math.
And
then we are surprised when things don't turn out as expected.
Some final thoughts
Correlation
is not causation.
All
numbers are random numbers drawn from a known or possibly unknown
population. If you don't know the population statistics your assessment of the numbers is
different than if you do.
All
random numbers need variance, standard deviation, and higher order moments
to be considered credible as sources of any analysis.
Drawing
a picture of the average of anything is very sporty
without the proper statistical analysis.
Read
Huff, reread it, read it all the time. Also go buy a good statistics and analysis book.
Start with Advanced Statistics Demystified.
If
there is an academic paper that is being used for public policy has not been
peer reviewed, and then throw it away. The Reinhard and Rogoff paper
is the basis of Paul Ryan's economic plan. He may have really good points,
but it built on sand.
Same
advice from self-proclaimed experts in anything, especially project
management. If there is a PhD thesis that has ZERO references in CITESEER,
ignore it.
Read more in the linked references below to see how bad statistics can go even more bad.
Download R, download the free books, learn how to think and act with credible statistics. Learn how many sample you need, learn how to assess the needed population statistics confidence levels, learn how to make decisions based on confidence levels not absolute numbers. We have a 70% confidence of completing on or before a date, or we have a 70% confidence or completing at or below of specific cost must be the answers when management asks about cost and schedule performance.
Every man, however wise, who begins by worshipping success, must end in mere mediocrity - G. K. Chesterson
If you're looking for the sure fire formula for success, be it business success or project success, you're going to be disappointed. There are ways to increase the probability of success. But only increase not assure.
Dan Ward has six suggested ways to success
Naivete - believing something can be done, even if it has never been done before
Recklessness - taking action even when a positive outcome is not guaranteed
Monomania - single-minded dedication to a particular goal
Cheating - doing the right thing even when no one else does
Spying - collecting, sorting, storing, accessing, using, and sharing information
Lt Col Dan Ward is the Test & Evaluation lead for the Theater Battle Control division of the USAF's new Life Cycle Management Center at Hanscom AFB.
Recent Comments