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Common Terms for Delay Analysis Methods

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Mike Testro
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Good Morning

There are no common terms for delay analysis methods that are recognised internationally.

What is needed is a common reference with readly recognisable descriptions.

This would be a relatively simple task for the Guild to put its marker on the map.

We all know what the methods are - they are the same in AACE and SCL but with conflicting acronyms.

All we have to do is come up with some simple two - maybe three - word titles that clearly summarise each technique.

Here are two suggestions.

Retrospective Reconstruction

Where the differences between the As Planned sequence and the As Built is demonstrated by reference to causal events and their effect on the planned sequence.

Likely Delay Effect

Where current events are impacted on the planned work in progress and the theoretical likely delay effect is demonstrated.

As Built v As Planned and As Built But For do not need changing.

Best regards

Mike Testro

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Rafael Davila
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If float does not matter then why so much fuss about not letting the contractor plan for early finish? Why not allowing the contractor to use "project buffers".

If float does not matter then why not allowing the contractor to take ownership using "feeding buffers" to take a portion or all of it?

Use of float comes at a cost, if contractor uses it it is at his own risk, at his own cost, if Owner uses it it is still at the contractor cost.

It has been an eternal debate, same as if abortion or pro-life. The problem with the AACEI is that it does not provides for contracts that allow the use of buffers, it explicitly prohibit them when it says "float belongs to whoever uses it first".

It promotes the bad practice of Owners taking ownership in a discriminate way. As said before Owners take float in construction jobs almost every single day they delay a submittal review that is not "critical", every day they make design changes that are not "critical", and the list goes on and on. AACEI is a one sided view that promotes their one sided view at the expense of others.

The NEC type of contracts are a practical attempt to make a more equitable distribution other than the extremes that make no justice to either party. Most probably not perfect, but should not be banned in our practice on this side of the Atlantic.

Not all free float consumption has an impact on the probability of success, only the last portion of the protected chains. In tight schedules the last portion is all of it. This can satisfy the need for both sides, better than one sided, is called Buffer Management.

Mike Testro
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Hi Patrick

I am trying to think of a standard from of contract that deals specifically with the subject of "float".

The NEC suite touches on it but only indirectly.

Perhaps you would enlighten me.

Best regards

Mike Testro

Patrick Weaver
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I tend to agree with Chris C in respect of the methodological approaches to forensic analysis – the AACEi are not inconsistent with the Construction Law Society’s Delay and Disruption Protocol: http://www.scl.org.uk/. Both sets of documentation are freely available.

I’m rather more surprised around the discussion on Float.  There is absolutely no ambiguity in respect of the meaning of the names and most contracts deal with the issue of who owns the float (bearing in mind float has no real existence). For more on the definitions and calculations of Float and Slack see: http://www.mosaicprojects.com.au/PDF/Schedule_Float.pdf  

Anoon Iimos
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Mr. Davila,

I don't know, but I never said that floats have no value at all.

For me, floats only serve as warning at the time.

If you're updating your schedule on a daily basis, then you will be warned daily.

As you know, some of the best things in life are free.

Rafael Davila
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Why owners want baseline schedules showing some float if it is free, of no value at all? Some go to the extreme of specifying a percentage of activities showing float, which is kind of stupid as anyone can add irrelevant activities as to make the requirement irrelevant.

Anoon Iimos
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Apologies to Mike for hijacking this thread.

Rafael,

I believe that there's a huge difference between floats calculated from a baseline plan as against the current plan. 

As I'm sure you knew that floats change everytime you reflect actuals. 

So costing a free thing that changes everytime you reflect reality, is something I believe nobody will buy. 

 

cheers!

Rafael Davila
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Anoon,

Photobucket

The best way to prove it is by running a probability analysis on your network schedule. Spider Project uses a mathematical model they call SPDM (see reference at the near end of my posting), similar to Monte Carlo, both are excellent methods.

From the above example the deterministic finish date is represented by the red dashed vertical line. If you target for this date you will have a 45% probability of finishing on time. If you use the same schedule for a completion date of one day latter the probability of success will increase dramatically. The earlier the target the better the probabilities.

This is a sample job of short duration and limited in activity count as to show the functionality with the free demo limits. In most jobs the distribution will be wider.  FYI I only made the run for the construction phase (WBS).

Photobucket

Applying the statistical theory to every job can be an overkill still unfortunately it is not used enough. Maybe because if you cannot target for early finish then your only option would be to increase free float by shortening duration of non critical activities but this will usually will have a very limited effect, if any. Our own protocols make ths statictical theory useless, merely observational.

I like the buffer approach because after the initial analysis you can set up a set of contractual buffers that are transparent and where the intention of targeting for early completion is a strategy to increase the probability of success and not an intention to take ownership of all float. For some jobs following the statistical analysis as the job progress and even increasing your buffer protection can be a useful strategy.

For most jobs some arbitrary allowance for your job buffer is enough, allow for the use of buffers and keep it simple unless otherwise justified. Always keeping the options open within your practices, don't close so many doors.

As a reference you might take a look at the following articles.

http://www.focusedperformance.com/articles/ccrisk.pdf

http://www.coepm.net/wp-content/uploads/Whitepapers/wp_scheduleriskanlysisA4_web.pdf

http://www.spiderproject.ru/library/SDPM_Canberra2004.pdf

In this sample job the buffers protected only contractors float, a similar analysis can be done at a higher level as to include the owner risk and assist on his strategy as to the contractual time that will protect his interests under his own control, same as the contractor wants to protect his.

Two thumbs up for the NEC, they are more than mere observers, they promote better practice.

http://www.neccontract.com/about/index.asp

Best regards,

Rafael

Anoon Iimos
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Thanks Rafael,

I think the idea of Float is that: It is a free time, and how can you sell a thing that is believed to be free in the first place? 

Float is an estimated free time, of course time is money. but in your plan, you are supposed to show and convince your Clients that floats are free.

Sa again, how to convince your Clients that it is not?  

Rafael Davila
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Anoon,

As always good to hear from you.

You are right about how difficult it is to estimate cost of float, perhaps it can be estimated as the cost to get back your job to the same position it was before float was used by the other party. This is quite difficult as in order to do so you might have to accelerate a selection of activities for the Monte Carlo simulation to show equal probability of success at the time of impact.

I believe the UK approach to allow some amount of Buffer activities is a practical way to get some fairness. The Contractor assumes the initial cost even when used by the Owner, the final part when used by the Owner is the one that the Contractor will be able to recover time and compensation.

Still somewhat unfair but better than what we have now. As people say here, it is better a "bad deal" than a "good case" as you never know how the court will decide.

Best regards,

Rafael

Anoon Iimos
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Rafael,

Please allow me to revise my question.

How to sell "Floats" in a project? 

I'm looking for a job right now and I wonder if you may hire me to assist you in estimating floats (and its cost)?

 

cheers!

Anoon Iimos
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Sorry to interrupt Gentlemen,

Just out of curiousity (from a common man's understanding): Float (whether Free or Total) means - The amount of time that you can delay a certain task or activity without affecting or delaying the overall estimated completion date. Is my undestanding correct? 

A schedule or a plan is just an estimate (as well as Floats) where I believe that anyone can make his own (estimate). An estimate whether correct or not is another question. 

A question for Rafael: Why should a "Float" can have cost? If the thinking that float is free in the first place (from an estimate), why is it a problem if who owns it? 

I believe that "Float" is free anybody can make an estimate and can make his own float, so how can you make a cost for floats? 

Rafael Davila
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Chris,

Here it is very common for the Owner to be in need to buy [without paying] float from the contractor. There are various "reasons", among them:

  1. Changes in the scope of work the Owner wants to make after the job starts such as the relocation of a building on a Vocational School and the new design took over a year.
  2. Even regular changes can absorb some float.
  3. Delays in the approval of submittals and shop drawings; the attitude, will take it easy, it does not matter as it is not critical (when not critical).
  4. Delays in answering RFIs that put a stop on some activities; the attitude, will take it easy, it does not matter as it is not critical (when not critical). Even if the RFI answer started to delay some activities as soon as the contractor took notice it is right away taking float.
  5. Errors and omissions; the attitude, will take it easy it does not matter as it is not critical (when not critical).
  6. Deffective specifications.
  7. Design changes.
  8. Late owner furnished equipment.
  9. Misfabricated owner furnished equipment and materials. Like some anchor bolts 4.5in dia x 20ft supplied by other owner contractor for the Arecibo Observatory, the anchor bolts did not fit on the anchor bolt as galvanizing after fabrication in the US increased their diameter.
  10. Unforeseen conditions; the attitude, will take it easy, it does not matter as it is not critical (when not critical).
  11. Access to work area denied on time, it does not matter there is still available float.
  12. Delay with some permits responsibility of the Owner that prevent work from starting on the portion of work under the permit requirement, offsite electrical and sanitary work frequently among them.
  13. a few more I do not recall at the moment.

It is not only how big each interruption is but how many and frequent.

It is good to know your position about this matter because I believe many in the Continental US share your views. It is the first time ever I talk to someone who belongs to such an organization , that don not necessary share all my views but listen and debate with an open mind.

Best regards,

Rafael

Chris Carson
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Rafael:  i understand that you feel that project ownership of float is unfair, and I tend to agree with you (although in the States at least it's pretty routine now) but my question was are you experiencing projects where the owner has to buy float from the contractor?  I am curious about whether this is a practice in your part of the world, or somewhere else that you know.

On my Linked-In Profile, I have posted a presentation that I gave with Patrick M. Kelly, now of Arcadis, regarding how to minimize the risks to the contractor when using dual schedules.  I have run into this request/need by contractors for years; where the contractor wants to operate with a more aggressive schedule as far as the subcontractors are concerned, but a less agressive, more pessimistic schedule for the owner/employer.  The presentation came about as an effort to work out a way to minimize the risk of a subcontractor claiming constructive acceleration and/or the owner claiming the difference as available float.  I see the schedule development as one of risk management, similar to what I believe you are espousing, where the aggressive schedule really does not contain all the coordination risk that is likely necessary.  I prefer transparent schedules as well and do not like to use dual schedules, but I've had enough clients who wanted them that I thought it was time to formalize the process.  Why don't you look it over and give me feedback?

Rather than say that the AACEi supports the project float ownership, I would say that the AACEi reflects the reality that this is the predominent position in the States and many other places.  The RP is designed to provide guidance and that guidance follows the standard/best practices that exist today.  It was not the intention to attempt to change minds about ownership of float but rather to show how to deal with that reality.

Thanks

Rafael Davila
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Photobucket

 

Mike,

Google for a preview of this old book and look inside. Time risk contingency is interpreted as a mockery of the urge to forbid early completion schedules. You got to submit the perfect prediction of the future, and that you shall use.

Schedules with buffers are not really targeting for early completion; but as the probabilistic approach tell us, they are schedules with a higher probability of success of finishing on time than a schedule targeting for a latter date. Our courts do not understand this concept, they live in a deterministic world. If your probabilities of finishing a month early are low most probably even if targeting for a month early completion you will finish late. If this happens they will say it is your fault and you were trying to steal some project float. But they steal all float.

They do not get the basic principle that you got to target for early completion in the hope of finishing on time. If the schedule is transparent then you assign more resources, a higher level of effort. In the short run you plan without inflated durations and as these durations increase your buffer absorbs them, until no more buffers, which is not uncommon.

I believe the UK shall keep the fredom of their practices and not copycat others.

Best regards,

Rafael

Mike Testro
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Hi Rafael

Are you saying that under the US judiciary a contractor is forebidden to add a his own time risk contingency to his own programme?

If so that bis a gross distortion of natural justice - the supreme court should take up the case.

Best regards

Mike Testro

Rafael Davila
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Mike,

It is indeed very prudent.

But we are not allowed to add a Contractors Time Risk Contingency Buffer, it is considered to be a mockery of the clause that says float is free, available to whoever takes it first. You take it first by hiding it, once shown "it belongs to the Project" is the prevailing assumption. You as contractor can use it at your cost and the Owner if reaches to it first can use it also at your cost, belong to the project is a catch. Depletion of project float comes at a cost someone must pay, but it is not fair to make the contractor to always pay for it especially if you are not even allowed a bit of float reserve unless you hide it.

My request is for a practice that allows the contractor to take control of his portion of the risk and be able to show it using the buffer activities in a transparent way it does not backfire against any party. A practice that do not forces the "wise" contractor to lie or the honest contractor to absorb all the risk.

You well know that if you inflate activity durations as to reserve some float ownership then if the activity is delayed to the point it consumes all float plus some of the inflated portion it will show a delayed job, when in reality it is not yet delayed and will open some float in other activities. This might prevent you from making otherwise valid claim on the float you hid. We prefer to be honest and transparent even when it hurts.

Best regards,

Rafael

Mike Testro
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Hi Rafael

The simple answer is for your contractors to put in an early claim to their float by adding a Contractors Time Risk Contingency Buffer to the programme.

This is prudent programming.

Best regards

Mike Testro

Rafael Davila
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Chris,

Here's a question for you; if the contractor owns the float, doesn't that mean that any time the owner creates a delay that consumes float, the contractor would be able to charge the owner for the float since it increases the risk?

Yes it increases the risk of late completion and in order to get back to a similar risk the contractor was before the event he must accelerate some activities. This cost money and it should be paid by the Owner. The theory that float is free is one sided.

Do you often see situations where the owner has to buy float from the contractor?  How is the price/day calculated?  It doesn't cost any more field overhead/general conditions; it just increases the risk.

As I said before the risk has a price, every time I see the Owner consuming too much of the available float this have an impact on the probabilities of finishing on time and it comes at a cost. The contractor should be reimbursed the "acceleration" cost he must take in order to get to a similar risk position he was before some of his buffer was taken away. If there is no agreement then he should be able to claim for constructive acceleration. The AACEI supports practice that closes the door for contemporaneous negotiation with regard to float and forces the Contractor into a disruption claim, this is not fair.

Many people consider near critical activities to be as relevant to timely completion as those with zero float without getting into the details of statistical analysis. Most software allows the scheduler to define criticality based on float other than zero.

The ACEEI position does not even attempt to provide for the Contractor to have some float reserve for the protection against abuse on his right to keep a level on his probabilities of finishing on time as high as he wishes, within practical cost and time limits. Yes it comes at a cost. This forces the contractor to submit a schedules that hides true float, this we frequently do but prefer a transparent schedule because these forced tricks can backfire, otherwise we would not be so concerned. If the contractor wants to increase his probabilities then let him bear the cost but do not steal away from his actual probabilities. The ACEEI position with regard to float ownership is one sided, is myopic, 100% leaning toward a single side.

Because statistical methods are complex for most jobs it does not mean shall be rejected. I believe alternate ways such as the acceptance of explicit contractor buffers as recognized under some UK Contracts are a practical compromise that allows for transparency and more equitable than none. Some may say more equitable and better than a contemporaneous negotiation. I am leaning toward the use of statistical methods to justify the initial level of buffers and thereafter using the buffers to keep it on a deterministic analysis. If the scheduler cannot make his buffer determination using statistical methods then some agreed maximum can be a practical approach. We can learn from the British approach but unfortunately most of our software do not have true buffer functionality as applied by Asta PP, one of their scheduling software.

For the moment some are forced to continue submitting schedules that hide float. I use Spider Project that allows me to keep two versions and update both at a single click of the mouse. Here some contractors do not like to submit a faulty schedule because it can backfire, this get them into a very difficult position. My clients fall under those who do not like to submit a faulty schedule, it is not fair. Most of our contracts prohibit early completion baseline and some go to the extreme of calling it a reduction in contract time. Not allowing for early completion without a reduction in contract time nor the use of explicit buffers prevent the honest contractor from managing his risk efficiently.

Best regards,

Rafael

Mike Testro
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Hi Chris

Regarding your second paragraph - things are different in the UK where there is no entitlement for "Loss of Opportunity"

If the approved programme shows an early completion date then the employer can use up the float for his own delays up to contract completion and the contractor has no recompense.

It is possible that an employer would not want to take posession of a building that will not attract any income but be liable for local taxes on completion.

Best regards

Mike Testro

Mike Testro
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Hi Chris

I was hired by Matthew Edwards on an EoT project in Kuwait so we are well aquainted.

I have heard of the the other three gentlemen but never met them.

I think Mr Lowesly was the co auther of the definitive book on delay analysis "About Time".

I have also published a tutorial on "Basic Priciples of Delay Analysis" which is an interactive power point presentation.

Available for download at www.planningacademy.org

Thanks for including me in the peer review - I will be happy to be involved.

Best regards

Mike Testro

Chris Carson
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Rafael;

Unfortunately you only quoted the last part of the section in the AACE FSA RP related to Ownership of Float, and that section addresses a different issue.  The first section clearly states, "In the absence of contrary contractual language, network float is a shared commodity between the owner and the contractor.  Conventional interpretation of the principle of shared float allows the use of float on a first-come-first-serve basis, thereby allowing the owner to delay activities on that path up to the point where the float is consumed." 

The section you quoted relates directly and only to the concept of Early Completion Schedules or the Right to Finish Early.  If the contractor submits an as-planned schedule showing earlier completion than the contractual requirement, in the RP's view, he has that right and if the owner creates a delay that pushes the completion of the project beyond his predicted as-planned completion date, but still earlier than the contractual completion, he can collect extended general conditions for that time, even if the delay did not prolong the contractual completion date.  This is an entirely different situation than the normal discussion about ownership of float.  The ownership of the network float is shared, by the AACEi's view.

My personal position is that the network float is owned by the contractor up to the point that he submits the schedule for approval since he has the ability to develop the schedule to manage his risk.  Once the as-planned schedule is submitted, the float belongs to the project.

Here's a question for you; if the contractor owns the float, doesn't that mean that any time the owner creates a delay that consumes float, the contractor would be able to charge the owner for the float since it increases the risk?  Years ago in the States, you could make this argument and sometimes have an owner pay for use of float, but it's been discredited for years.

Do you often see situations where the owner has to buy float from the contractor?  How is the price/day calculated?  It doesn't cost any more field overhead/general conditions; it just increases the risk.

Chris Carson
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Mike:

Have you spoken to Matthew Edwards of Planning Planet?  He is based in Dublin, but is managing the accreditation effort.  I'm not actually sure who is in charge of the UK effort in general, but Geoff Mann, Richard Croxson, and Stephen Lowesley are the primary authors for the Forensic Schedule Analysis Guide (soon to be renamed the Standard of Practice, I believe).  Do you know any of them?  I am not aware of any blackball going on in this effort, so I doubt that you're being blocked, it's much more likely that they are all just busy and perhaps someone hasn't done a good job of communication.  Just as in AACEi and the PMI College of Scheduling, we are all volunteers and these efforts take a considerable amount of time and effort and it's easy to get buried in the details and not really handle the volunteer coordination well.  In the CoS effort, we've joked for years that we get 10% of the 1600 person membership who volunteer to help out with our Best Practices and Guidelines for Scheduling, and 10% of the volunteers who actually produce anything, and some of those only do a little bit.  It does seem to be somewhat true; we have a core group of less than a dozen working hard, and maybe another dozen who are contibuting sporatically (we are grateful for any help and that is very useful).

We are rolling out the Guild basic information on 11-11-11, so I'll make sure at the least that you are included in peer review.  i think it may be too late to contribute much in the way of the original text.  But peer review is valuable and it enhances our efforts.

Rafael Davila
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Chris,

When I talk about the UK practice I do not limit my reference to the SCL Protocol. The NEC2 and NEC3 forms of contract are used in the UK and their interpretation is not the same as AACEI RP or the SCL Protocol.

With regard to float ownership I am with the ‘project float’ approach of NEC2 and NEC3 forms of contract and that in the absence of contrary language, project float is owned solely by the contractor. I do not understand how in the absence of contrary language float is not owned solely by the contractor, if the contract is not clear then it shall be interpreted as how the party who did not wrote the contract can interpret it.

From Forensic Scheduling Analysis - Recommended Practice or Protocol: What’s the Difference? By Anthony Caletka

Float Ownership

The FSA states that:

“Project Float is the time between the last schedule activity on the baseline schedule and the contractual completion date ... in the absence of contrary language, project float is owned solely by the contractor. ”

This interpretation of float ownership is not consistent with the SCL Protocol’s recommendation that project float is a shared resource, to be determined on a ‘first-come, first-serve’ basis in the absence of express provisions in the contract stating otherwise. The SCL Protocol does recognize that direct costs related to delays to non-critical activities may be compensable, but not time related costs typically quantified as ‘prolongation’.

The FSA approach is consistent with both the NEC2 and NEC3 form of contract which bases EOT and compensable delay upon the contractor’s “planned” completion date, which may include a period of ‘project float’.

Best regards,

Rafael

Mike Testro
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Hi Chris

My brief definition od Retrospective Reconstruction could easily be expanded to include programme fragnets etc - perhaps we should concentrate on getting the description right.

I have been asking to get involved in the Guild work for some time now but with no reaction - I suspect I am being blocked by someone.

I would certainly like to be involved in the peer review for delay analysis. Hopefully it will follow my maxim for any form of narrative in that it has to be so simple that even a Judge can understand it.

Best regards

Mike Testro

Chris Carson
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Rafael:

OK, I got it; you don't like the AACEi and the initiative that we did take, and I won't try to answer all your complaints/comments, right or wrong. 

You do however comment that in the UK they understand that reduction of float raises risks of completion.  I think everyone agrees with this, but even the SCL Protocol, from the UK, states that the Protocol "has the effect that float is not time for the exclusive use or benefit of either the Employer or the Contractor."  So, even though lessened float affects risk, the Protocol envisions that the Employer can take that float without costs.  This is the same approach in the US, and followed in the AACEi RPs.

Mike:

There is no question of my supporting the PP efforts; I am deeply involved in helping with developing the Guild, including writing of the Planners Users Guide as well as the Forensic Analysis Guide, as well as the other guides that will comprise all the disciplines of project controls.  I think PP and the Guild are going to lead the international community, which includes the US, in project controls efforts and resources.

And you reinforce my original comment; a taxonomy that describes the methodology would allow us to understand each other; the FSA RP does this.  As far as I know, the IAP is the same in the US as it is in the UK.

In your Retrospective Reconstruction however, you described it as "Where the differences between the As Planned sequence and the As Built is demonstrated by reference to causal events and their effect on the planned sequence."  This description doesn not appear to include modeling the delays; reference to causal events sounds like a research effort, not an effort to model and insert activities to represent the delays, as would be done in an IAP.  You see why even in your first effort, we could not understand each other.  I did not see where that description intended to include fragnet activity insertion.

I'll be glad to see your efforts at coming up with new names that are definitive descriptions of the different methodologies, should be interesting.  Two claims experts in the US, Tom Driscoll and Robert D'Onofrio, believe that there are something like 11 different analysis methodologies.  That will an interesting discussion when they publish something in the spring.

So good luck with that effort and I hope you are participating in the PP/Guild; certainly in the Forensic Schedule Analysis Guide/Standard of Practice for PP, we are using the common names generally, so there may be some solution to your need, and they will go out for peer revew once the draft is complete.  We expect to correlate them with the AACEi's FSA RP as well.

Rafael Davila
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Mike,

AACEI is not a binding code here, I have never before heard of it other than in PP, but we need a good reference. As the choice of method is by the claimant I suppose here most have decided not to use it for similar reasons I would not. I do not like it as it is of today, so I am still looking for the reference of my choice, similar to what happened a couple of years ago when I was looking for a replacement for our Primavera software, it took me long to open my mind to Asta PP and Spider Project. I tried both, liked both and on both cases the response from the developer was much above what I was used.

I do not believe in Monopolies so I would ask for the British to keep their own recommended practice, perhaps organized in a similar way as the AACEI but with their own procedures. AACEI is way too back in time or too local, their protocol do not recognize common practice in the UK for a better distribution of float and complicates things with the concept of Negative Float Criticality that might be absent on British practice and perhaps on British common law. Perhaps you can go with the analysis in a way that eliminate constraints that create negative float as negative float makes the analysis harder. I believe the procedure shall take into account the audience, it is not merely the scientific community but the Contractor, the Owner, the Architect and Adjudicators that make the decisions and not an elite brainwashed into a limited protocol who makes the decisions.

We are used to the attention to details, tedious but but it is not rocket science, keep it simple there is no need for languagus vulgaruis. Keep the options open.

If both sides can keep common names for equivalent procedures but still allowing for some differences it would help. If one side insists on keeping languagus vulgaruis the other side is not obliged to, you can use your own common names and make a table of equivalencies so the user of your protocol can easily match them for reference. Maybe you do not need to mimic AACEI toxicology to classify your methods, the table of equivalencies would be enough. Some competition as to which is more useful can do no harm but benefit all of us, better two references than a single one.

I am still looking for a Spanish or English language reference for Delay Analysis because here both are official languages, it does not have to be American it can be British, as long as it is from an internationally recognized source it can be from anywhere.

Steve Jobs would have democratized the recommended practice and called it The RP for the rest of us.

Best regards,

Rafael

Mike Testro
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Hi Rafael

In the UK the SCL Protocol 2002 was a guidance document and is now out of date and does contain some errors.

It is however still a useful reference book.

I am imagine the AACE has a similar status in the US and not a binding code of practice.

BTW your neighbour must have a mighty Felis Catus or your Canus Familiaris was a real wimp.

Me i'm just a plannerii vulgaris.

Best regards

Mike Testro

Mike Testro
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Hi Chris

My Retrospective Reconstruction was based on the UK IAP.

I assume APAB means As Planned v As Built - which is totally different to IAP or whatever you call it in USA.

So maybe you can see the dilemma that us poor mortals face when trying to communicate across the globe.

We definitely need an universally understood set of definitions and I think the PP Guild is best placed to achieve this.

So please support our efforts.

Best regards

Mike Testro

Rafael Davila
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Chris,

I can understand your perception about AACEI always being correct, but even Einsten was proved wrong long ago by Georges Lemaitre and is about to be proved wrong again this time with his theory of relativity. 

The AACEI RP 49R-06 have some errors of its own. In their Recommended Practice 49R-06, under Lag Calendars they say only Deltek's Open Plan CPM software allows for the assignment of different work calendars to individual relationships. They are wrong, for over a decade Spider Project had this functionality. I will say they are wrong twice because in Spider Project "double links" a single link type might have two independent calendars each independent of predecessor and successor calendars. And if this is not enough they also miss that in Spider Project you can have "volume lag" these are different to time lag (of fixed duration) but volume lag that models a variable duration based the volume of work which as the activity/schedule progress can change, volume lag for duration type activity is the activity calendar while for productivity type is a combination of activity and resource calendars this can also make relationships to be modeling the wrong lag when your model calls for it and you substitute it with different functionality. Again I would say they are wrong many times with regard to how many calendars can be assigned to a single link. This is way too much to be overlooked.

This might not be relevant for those who do not know or understand how this work but is an unquestionable proof that AACEI can be wrong. For some of us the limited functionality of the CPM of the 70s is not enough and the more advanced functionalities are relevant.

There are other important issues many do not agree with AACEI in their protocols, the most notable is the presumption on their procedures that float is free, that it belongs to whoever uses it first, common in all their RP's. It does not acknowledge that in other jurisdictions such as in the UK it is recognized that the use of float can significantly reduce your probabilities of finishing on time, the Europeans allow for a more equitable distribution of risk into their contracts. The AACEI in their omission promote only one option, an inequitable option, their delay protocol AACEI 29R-03 of 2011 is useless on the analysis of contracts with this kind of clause, not uncommon in Europe where some of their software use the functionality they call "Buffers" to handle this apportionment of float. Some call it Critical Chain others SDPM or Success Driven Project Management Methodology, two methodologies that can be integrated for further benefit. The AACEI response, claim it as Disruption, this after all damage is done.

Take a look at an excellent software from the UK, Asta Power Project, they have this functionality for buffers integrated into their software while Spider Project follows SPDM. I like both approaches, Asta uses agreed buffer activities while Spider use the concept of Most Probable Schedule to bridge the gap between probabilistic approach and the deterministic.  AACEI shall not close the doors to those methods in their forensic methodologies. AACEI shall move with the times, scheduling tools shall not be static, they got to evolve. They are not like biological species that take thousands of years to evolve a little.

When you go to court you say my dog was killed by his cat, you do not say my Animalia-Chordata-Mamalia-Carnivora-Canidae-Canis-Canis Familiaris was killed by his Animalia-Chordata-Mamalia-Carnivora-Felidae-Felis-Felis catus. The AACEI naming is no good, is not practical. The natural tendency of human beings to speak common language will end up in some cases for 3.4 be named Windows Analysis while in other cases the Windows Analysis name will be applied to 3.2, or 3.3, or 3.5 or 3.7 or 3.9. even when all cases making reference to the AACEI RP. Avoiding the definition of standarized common names is calling for chaos.

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I appreciate the effort made by AACEI contributors most of which contribute for free with their time and effort. In order to keep them showing their best we have a responsibility to challenge them, the more we challenge them the better their performance will be, if we say nothing they listen nothing.

Best regards,
Rafael

Chris Carson
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I believe that the AACEi has taken the lead and provided a very good approach to naming the methodologies.  With the AACEi's Forensic Schedule Analysis Recommended Practice, the names of the methodologies were derived from the taxonomic classification which according to the RP "will allow the freedom of regional, cultural, and temporal differences in the use of common names for these methods."   Recognizing that I am biased due to my work on the RP, I still believe that it's the best approach to CPM schedule analysis methods.

An excerpt from the RP explains the benefits and rationale for the RP's approach, "The RP correlates the common names for the various methods to taxonomic names much like the biosciences use Latin taxonomic terms to correlate regionally diverse common names of plants and animals. This allows the common variations in terminology to coexist with a more objective and uniform language of technical classification. For example, the implementation of method implementation protocol (MIP) 3.7 (aka "TIA") has a bewildering array of regional variations. Not only that, the method undergoes periodic evolutionary changes while maintaining the same name."

I have been using these taxonomic classifications now for several years in our offices, and they have simplified the discussions since everyone knows what the terms stand for.  I think you should look at the RP before attempting to come up with your simplified names.

In your initial suggestions, there is confusion:  with your "retrospective reconstruction" you've defined it as a type of APAB, and then suggest that this is different from the traditional APAB.  See the problem, trying to describe methodologies by choosing new specific names for methods just adds more random names to the industry.  Please take a good look at the AACEi's efforts in the RP and I think you will find that the taxonomy approach is very usable.

Rafael Davila
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Definitively I support your initiative, the lack of uniformity affects everyone. As you said the key is on word titles that clearly summarize each technique, easy to call and remember by mere mortals. If the AACEI nor the SCL took the initiative then it is still an unresolved issue and the Guild can raise the debate.

I suggest for the prospective modes of TIA and Windows Analysis adding the prefix Prospective, for their retrospective mode, whatever method finally get its name shall have the prefix Retrospective, resolve the controversy once and for all, define the terminology in common language.