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Activity on Arrow and Non-Continuous PDM are wrong.

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Rafael Davila
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There are several reasons to avoid the use of the traditional Activity on Arrow computations and the Non-Continuous PDM (its PDM equivalent).

First and obvious reason is that by an overwhelming preference the Activity on Arrow representation is not used because of the complications the need for the Dummy Activity creates. In complex projects this burden can be overwhelming. This drawback is not existent under the Non-Continuous PDM version but the following statements still apply to both representations.

Second because it provides the dates for the nodes and not the activity, therefore it assumes the activity to be discontinuous with one end driven by the first node and the last end driven by the last node. In the majority of scheduling need the most efficient scheduling of an activity is for it to be continuous. The method denies the scheduler for the use of Continuous scheduling while by merely splitting the activity the Continuous method do allows for the proper application of the splits.

Third, if you need for an activity to be discontinuous this assumption should not be automated as the splitting rule must be determined on a per activity basis, and then there is no benefit on the automation of a rule that must be on a case by case. In addition the splits do have a particular duration of their own, early start and early finish of their own, float of their own which can be different after resource leveling. Because the software summarizes this under a single activity line this information is hidden to the user.

Replies

Rodel,
I can send you funny example of MSP levelling if you are interested and will send me your E-mail.
Usually PM packages use some default levelling algorithm and may suggest to select other priority fields like P6, Open Plan, Spider (in Standard option) do.
You discovered that P6 default levelling priority is Activity ID, in P3 it was Late Start, Total Float.
MS project describes one algorithm in its Help but uses another. Both are too primitive and produce poor schedules.
Best Regards,
Vladimir
Rodel Marasigan
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Hi Vladimir,
Look what I found in MSP. It use the longer duration of parallel activity as leveling priority. (see below) Very interesting.
Purchase MSP

Best Regards,
Rodel
Rodel Marasigan
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Vladimir,
Thanks, I just assumed and I not saying it am correct. I’m just wondering what would be the basis of sequence or leveling priority of any Planning application when leveling.

Best Regards,
Rodel
Rodel,
activity ID does not play any role in Spider levelling.
We recommend our users to make their activity IDs meaning what is activity type, where it is, who is performing, etc - not numeric but text based. There is no such thing as proper order of activity IDs.

It would be strange if changing activity code will change the schedule. For manual prioritization we use Priority field.

So P6 default activity levelling priority is Activity ID. Thank you for the information. I did not know this.

Best Regards,
Vladimir
Rodel Marasigan
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Hi Vladimir,

Correct me please if I’m wrong. I found on our exercise schedule that activity id was not in properly order. “Market Analysis” has an activity id of 1010 while the “Technical Requirements” 1020. When I change the “Technical Requirements” activity id to 1010, “Market Analysis” to 1020 and change the Activity leveling priority as 3-Normal for all task and level again it has the same result as the post # 164 by Rafael. I assumed that the default leveling priority for P6 is activity id where most of the application may be doing the same. My understanding on computer is garbage in garbage out. Meaning it will not necessary decide on their own without any basis. I’m just wondering what will be the basis of leveling priority for Spider Project when running an optimal result, would it be same. (see below)
Purchase Fig 7

Best Regards,
Rodel
Yes, you are right, but these priorities still produce poor schedules. Even for the project that we scheduled none of them produce good result. But for my surprise if to run levelling several times using the same priority the schedule will change each time and even become optimal (for this particular example). But unstable schedule create different problems.

This approach - selecting the priority among activity fields we call Standard. But in Spider Project you can also select Optimization and may be sure that the schedule is close to optimum.

And manual levelling is exhausting exersize in any case - even when the schedule is properly created. And I don’t think that this is the way to find the best solution in the large schedules.

Best Regards,
Vladimir
Rodel Marasigan
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Hi Vladimir,
I agree that deciding which activities will have a better priority on activities running parallel will be a tedious task if a planner not doesn’t know which one is which and the logic is not properly applied on the schedule but those options that we did are just an example to match the example presented. A planner can use other leveling priorities like Activity ID, Total Float, Free float, Durations, Early Start and etc... that will help the planner to have a good result. I believed that option is created for a better purpose and not just a display.

Best Regards,
Rodel
Rafael,
I think that the ways of using Spider is proper to discuss in Spider Project forum.
We recommend to apply Spider risk management - this is the best way to manage projects.
Vladimir
Rodel,
construction projects consist of thousands activities and use at least several dozens resources.
Your decision on activity priorities will change the schedule, next decision will change the schedule, etc. Can you imagine the number of choices? But the problem is much more complicated - these decisions are made one after another, but matters their combination. It is impossible to try them all.

Just imagine that I will send you the schedule consisting of 6000 activities and approximately 70 assigned resources and suggest to find the best schedule. What time do you expect to spend searching for this solution? And I am not sure that the result of your efforts will be successful.

Best Regards,
Vladimir
Rafael Davila
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Vladimir,

As you know a few months ago we switched to Spider Project and believe me it has not been like a daily change of underwear, or twice when an accident. We still got some way to go until we feel fully comfortable on our use of Spider Project. Therefore I would like you to comment on our approach to keep some control of the leveling.

We do our basic resource leveling using “standard” algorithm or “advanced” and in this way we can keep prioritization. If the schedule revision does not yet extend project duration we choose either one. At time we combine the scheduling algorithms with ”soft logic” we toggle on and off either at the links table (the eawsy way) or by using formulas and even by using Reference Books functionality where we can manipulate table values. If still the job is predicted to be late after the exercise then we choose “optimum”. Unfortunately once in need to exclusively use “optimum” is because it is so behind we end up using the option until the end of the job. This happens in about 25% of our jobs, even when frequently is because of correction to the drawings by others we never get back full EOT.

Best regards,
Rafael
Rodel Marasigan
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Vladimir,
Correct me if I’m wrong. A planner is applying manual priority to those activities that running parallel and decides which one have a better priority if leveling the resource. I don’t think too many parallel activities that have same resource at the same time if the schedules are using a proper logic.

Best Regards,
Rodel
Rodel,
applying manual priorities is the same as levelling projects manually. If the the number of activities is small it is possible, for large projects you will not know what priorities to change.
I don’t think that such what if estimates are practical in the real schedules.
Best Regards,
Vladimir
Rafael Davila
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Vladimir and Rodel,

We previously tested a sample job in which the scheduler using other software figured it out by whatever methodology a priority set that would yield similar results but the trick of running several runs in sequence is new to me.

I still wonder if in complex jobs, with thousands of activities and many trades working on the job it is practical or even possible to manually prioritize among thousands of activities and get optimal and second if the trick of running in sequence the resource leveling routine will work and in how many runs.

P6 might work for those who are comfortable with playing with prioritization and running multiple resource leveling runs, for us it is not a practical solution. It is quite a burden on us when we are forced to use software as bad as P6, software we do not know.

We were SureTrak users before switching to Spider Project and we were forced several times to use MS Project and P3, about P6 not yet and sure it will happen. At one job we were quoting, different web based software was required, it was not P6 web. This one we perceived it as breaking into our privacy as all we do was to be stored at their website servers even if not formally released, we were not even in possession of the files and if a claim in court was to be raised we had no guarantee the files were not manipulated by the agency.

Best regards,
Rafael
Rodel Marasigan
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Hi Vladimir,
That’s what I did. I schedule the project first and change the leveling priority as shown on the figure that I posted (see 1st column). I change task "Technical Requirements" as 1-Top and the rest are 3-normal then level again. I also change back the leveling priority to 3-Normal for all and I goes back to the original result that I posted for comparison (Post #160 & #158)

Best Regards,
Rodel
Hi Rafael,
when we first launched Lite version of Spider Project we decided that our users will require only Optimization and Previous version support levelling algorithms and excluded Standard option.
But many people asked us to keep Standard option as well.
They created Standard schedules for their Clients but used optimization for themselves.
So we added Standard option to the Lite version.

By Standard we mean the approaches supported by other packages (P3, P6, Open Plan). The approach was explained by Rodel in his previous message - play with different criteria and select the best result. When resource competition is not high some standard levelling priority may give the solution that is optimal. Since standard scheduling is faster the planner may select to use this selected standard option.

Rodel opened my eyes that P6 uses something similar.
When you level your project first time you get some schedule that is far from optimal. But if you level again using the same levelling priority you may get better schedule, on the third run you may get even better (or worse) schedule. So wise planner will level the project many times and will select what schedule to submit to the customer and what to keep for himself. There is only one problem - with each run he will get different schedule, and after entering actual information he shall repeat the trick and still may get the schedules that are not similar to the initial. I am not sure that your Client and suppliers will be happy if the planned order of works will change frequently. And besides in large projects you will still be far from optimal decision.

When I discussed this example at IPMA congress in Paris in 1996 Open Plan representative proudly told me that they found the decision - if to run levelling twice in a row using Scheduled Float criterion they get the optimal solution for this example.

So the advise for P6 users - never run the levelling once using certain levelling criteria. If you have done it only once then after entering actuals you may get quite different schedule when you will plan next project period even if the same levelling priority is applyed.
And previous Rodel advise - discard default levelling options.

This discussion was very useful to me. I did not look at P6 levelling for a long time and did not test it thoroughly.

Best Regards,
Vladimir
Hi Rodel,
please inform us what levelling priority did you use.
And I suggest to repeat the levelling from the beginning - first schedule the project and then level. Are the results the same?

Best Regards,
Vladimir
Rodel Marasigan
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Hi Rafael,

I think this is more on ability of the planner on how they can decide on what is the best for their project by doing different what if scenario.

As per your example I did the same in P6. I change the leveling priorities and it have the same output as per your example below.
Purchase Fig 6
Rafael Davila
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Vladimir,

Is a difference of 3 weeks in 15 as per Spider Project resource leveling algorithm, is just a 20% overrun. Maybe contractors are granted for a 20% overrun before liquidated damages are applied. Perhaps the issue is in the inability of the scheduler to set up the hidden settings, perhaps is not in the software. We can make Spider as bad as P6 and use a substandard leveling algorithm, like the one we have for comparison purposes.

Software Selection

Why do you insist in calling the Substandard option as Standard? Call it by its meaning, Substandard.

Best Regards,
Rafael
Rafael,
you did not appreciate that P6 creates poor schedule that you can submit to the Client but shows you (secretly?) that the very first activity of this schedule has total float (look at the Rodel schedule). And if you will adjust the schedule manually (or using Spider Project) you will own this float and use the best schedule for yourself and P6 schedule for your Client.
Everything has its good sides.

Best Regards,
Vladimir
Rafael Davila
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Vladimir,

Here we as a Contractor are frequently required to change software as if a change of underwear and we are supposed to know the hidden traps of the foreign to our company and imposed software, or even worst, outsource an integral part of our management by using an external scheduler. Even if we on the run can spot that P6 resource leveling depends on us to bypass default setting to my eyes is a design horror.

If the resource leveling routine cannot be set to extend project duration by not allowing over-allocation then it will prevent the contractor to show when an Owner caused delay is delaying the job because of resource availability as this will have the effect to allow for unlimited resources when the unavailable resources should extend project duration. When the delay is hidden by the schedule resource leveling it will create an illusion that everything is OK and this may create problems. It is self serving to the interest of the Owner at the expense of the Contractor.

This is another reason why I always have been critical about Primavera as I always perceived the company as biased in favor of the Owner, always at the expense of the Contractor.

Best regards,
Rafael
Hi Rodel,
thank you for the explanation, because Preserve schedule Early and Late dates is P6 default levelling option.
So floats depend on the levelling settings.
First activity float shows that the schedule is not optimal, very very nice.
Best Regards,
Vladimir
Rodel Marasigan
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I agree Rafael, that is why Preserve schedule early and late date should not be used when levelling resources. It is used only for analysis and comparing the movement of dates after the levelling. If proper levelling is done, the correct float will be given.

See belowcomparison:

Using Preserve schedule early and late date option:
Early and late date did not update and remain as original compare to start and finish date.
Purchase Fig 3

Proper levelling without using any option. Early and Late dates are updated as shown on Start & Finish dates.
Purchase Fig 4

Best Regards,
Rodel
Rafael Davila
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Rodel,

I do not have P6 so the answer must come from Vladimir. But here we are required to schedule using early dates and get results for float showing early dates.

Total float is calculated by subtracting the early finish date from the late finish date (start dates can be used instead). We are required to display early schedule and the difference between early and late dates is how float is computed, not sure if what you are displaying with the second option is the difference between late dates prior and late dates after leveling which can be different.

Best regards,
Rafael
Rodel Marasigan
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Hi Rafael,
Thanks for the xer and correct me if I’m wrong. I downloaded the files that you shared and do the exercise. I suspect that the screenshot that you posted is level the resource using “Preserved scheduled early and late dates” options that its why it not showing the correct float. It forced primavera to retain early date which is the basis of calculating float. As shown below.
Purchase Fig 1
Note: I change the resource name to match on the screen shot that you used.

Here is the explanation using that option:
If you mark the Preserve Scheduled Early and Late Dates checkbox, the project’s current early dates are retained before levelling. In addition, when you preserve these dates, the module only forward-levels the schedule, which means that the early dates of activities from the start to the finish of the project are scheduled.
To review the levelled early dates, I show the Start and Finish dates to compare Early Start and Early Finish date as shown on the figure above.

If you clear the Preserve Scheduled Early and Late Dates checkbox, the module also performs backward levelling. Backward levelling schedules activities to occur as late as possible without delaying the project finish. The module reverses the levelling process, beginning at the project’s late finish and working towards the beginning of the project. If insufficient resources are available to schedule an activity on its late dates, the activity is advanced to an earlier date. When the schedule is levelled forward and backward (by clearing the checkbox to preserve scheduled early and late dates), the project’s early and late start/finish dates are updated as shown below.

Purchase Fig 2
On this exercise P6 clearly show that resource levelling facility is correct.

Best Regards,
Rodel
Rafael Davila
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Sorry,

You are the first who took notice which means nobody is checking on the files to verify on my claim. And I was hoping for someone in the US Federal Government, the US General Service Administration and a few others who specify CPM software were to check on these. I believe it would be a great shame to them if what they specify is proved to be so deficient. To me would be like take it as it is and pretend there is no error, in any case assume even if the specified scheduling tool is wrong the blame is on the Contractor.

Let me know if it matches as I do not have P6.

http://rapidshare.com/files/376343421/Purchase.xer

Best regards,
Rafael
Rodel Marasigan
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Hi Rafael,
I believed you shared wrong xer. It was the first exercise and not the same as what you posted.

Thanks,
Rodel
Rafael Davila
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Vladimir,

I just received your screen capture of a schedule you previously sent me in Spider Project format, and I believe it was part of the demo version or older Spider Version. I no longer have it nor do I have P6 so your help will be appreciated.

The float displayed by the last activity as you pointed out is quite weird.

Software Selection P6

UNBELIEVABLE

You can download the xer file from the following link:

http://rapidshare.com/files/375350976/Test.xer

Because I do not have P6 I would appreciate if anyone send me a print out of the calendars used in this job from –a year to +a year of the job duration to make sure there is no trick there.

ENJOY

Best regards,
Rafael
Rafael Davila
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Vladimir,

Thank you a lot, also appreciate and now perfectly understand why float bars are not displayed, for me is not just that they are not 100% part of the solution set but that if assumed continuous can lead to serious disruption of the schedule, this is a fact all should understand, the Owner and the unwary Contractor. We all know that if a contractor by his own actions disrupts his schedule he cannot issue a claim and here is a possible trap for this to happen. Precisely this is the kind of debate I hope we will be talking with all when eventually most software get it right about resource float.

I would appreciate any help of yours with the sample jobs becuase you are way ahead of me with the understanding of this issue.

Best regards,
Rafael
Rafael,
finish float can differ from the start float if resources are assigned as independent teams (first shift and second shift as an example). The certain portion of an activity shall be done before other activity can start and let’s suppose that this other activity is critical. So this preceding portion of an activity is critical too. But later portion may be delayed. If assignments are independent (first shift, second shift) then the last portion of an activity can be delayed.
This is discontinious model and rather artificial but may happen in PDM.
Best Regards,
Vladimir
Rafael Davila
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Vladimir,

Can I say that Spider Project single value is correct for activity start or finish because it is based on a Continuous PDM Model, that Non-continuous PDM model could yield differnet values for start float and finish float if activity is non continuous at the moment of performing the computations?

By the way the following article can be of interest to those still using Activity on Arrow software.

http://research.economics.unsw.edu.au/ctseng/Float.pdf

- "In the context of activity-on-arrow (AOA) network representation, textbooks on project management, based on our survey, have for decades been using a popular formula to calculate free floats that may lead to erroneous results in the presence of dummy arcs."

Best regards,
Rafael
Hi Mimoune,
I think that this question is to me.
Spider Project calculates forward and backward resource constrained schedules and the float shows maximal delay of activity start (or finish) that does not delay project finish.
It does not mean that intermediate delays are acceptable.
Spider Project also calculates resource assignment floats and there are examples that activity is critical (its start cannot be delayed) but has finish float (the work is done by another shift).

You may notice that Spider Project shows early and late bars for activity dates and not the lines for activity floats.

Best Regards,
Vladimir
Rafael Davila
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mimoune,

Because it is just 2 days float in this case yes. This sample job cannot illustrate my second statement that you cannot always place at will the activity somewhere in between the late bar and early bar without it becoming in conflict with availability of resources. There got to be available idle resources for your bar relocation(s).

I am working on a quantity take off for a bid but tomorrow will try to create a sample job to illustrate my second statement in a way you can manually move the bar in between early and late bar and resource availability is not there.

Best regards,
Rafael
mimoune djouallah
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Rafael thanks

please i need a simple answer

did the total float shown by spider project, respect those conditions ( resource max usage, and network logic)for all the duration of the said float.

Best regards
Mimoune
Rafael Davila
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mimoune

This is supposed to mean that if activity is delayed to occur at late bar it will not be overloaded.

Note that there might be instances between early bar and late bar the activity cannot be rescheduled without overloading, this is a trap with resource constraining we must be aware.

Vladimir,

Plase correct me if I am wrong.

I know at times it is needed to model volume lag but I am keeping the issue out as not to camplicate modeling of lag any further.

Rodel,

Do you mean P6 lag cannot have its own calendar, that got to be either predecessor or successor calendar across the board. In occasions I have the need to model lag using a different calendar than predecessor or successor and in other occasions when successor and predecessor calendars are different my model requires for it in some instances to be successor and in other to be predecessor.

At times we use a calendar for lag different from successor and predecessor activities such as when specs require for you to wait a specific time duration for backfilling, less if concrete cores yield a certain strength, while at times the minimum stripping time is to prevent concrete creep so time can have precedence even when strength is achieved, we model lag using the appropriate calendar.

There are other occasions where this happens but the illustration is from a draft schedule of a job that is about to start.

lag calendar

Best regards,
Rafael
mimoune djouallah
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Seriously

please this is a very simple question for every body.

if a software after leveling ( respecting maximum availability of resources and network logic) say that an activity has for example 15 days of total float.
what does that suppose to mean !?

best regards
Rodel Marasigan
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Rafael,
You can read PMRefMan if you need to understand your entire question as it will cover all the pages here in PP. Its self explanatory and I use default option when running resource leveling.

Ex: “Calendar for scheduling Relationship Lag ........................Predecessor Activity Calendar”
It is an option where most of Planning Software now is using to calculate relationship lag. The default on MS Project 98 to 2002 version, P3 and others planning software is Predecessor Activity Calendar. In P6 you can select as shown on my post link below.
.xer to .prx Post #6

Cannot leveled means not leveling that particuar activity (Forward, Backward) Please refer to the manual link below.
Primavera 6.1 Reference Manual

Best Regards,
Rodel
Rafael Davila
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Rodel,

I cannot understand some of the settings as they are particular to P6, one that I do not understand is the setting for relationship lag calendar:

Calendar for scheduling Relationship Lag ........................Predecessor Activity Calendar

I must assume there is the option to define an individual calendar for every relationship. For example in some links the lag can be set by work days calendar while in other occasions it got to be modeled using calendar days even when successor and predecessor calendars are in work days. Take for example bonding agent and cement plaster, if during a week end the lag between the two shall be modeled as per a different calendar used by both activities. I thought this was available on P6.

Also cannot understand use Expected Finish date as in Primavera SureTrak Expected Finish Dates is not a constraint per se but a subroutine that re-compute remaining durations.

About Progress Override is a setting banned in our specs.

About Compute Total Float As Start Float, does it means you can redefine float and get different results? Total float cannot be both, there shall be a standard. I heard of other software that go as far as allowing you to add a third definition, the maximum of Start and Finish float, it can be anything you want it to be.

I cannot not see a warning telling that the displayed value of float for activity A1010 will delay the job completion or will result in an over-allocation.

I cannot understand “Activity that cannot be leveled A1010”.

Perhaps with this you will understand how unfair it is to force a Contractor to use scheduling software other than his own.

Best regards,
Rafael
Rodel Marasigan
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R. Catalan,
I’m cooled as the weather here in Melbourne is starting too breezed... and don’t mean for any fight.
I respect Rafael’s opinion but we stand P6 is correct.

Rafael,
Below is the report as requested.
Scheduling/Leveling Report - 15-Apr-10 12:09 AM - PM.exe
========================================================

Default Project..................................................Test

Projects:
Test............................................................Test For Resource Leveling

Scheduling/Leveling Settings:
-----------------------------
General
-------
Scheduling ......................................................Yes
Leveling ........................................................Yes
Ignore relationships to and from other projects .................Yes
Make open-ended activities critical .............................No
Use Expected Finish Dates .......................................Yes
Schedule automatically when a change affects dates ..............No
Level resources during scheduling ...............................No
Recalculate assignment costs after scheduling ...................No
When scheduling progressed activities use .......................Progress Override
Calculate start-to-start lag from ...............................Actual Start
Define critical activities as Total Float less than or equal to .0
Compute Total Float As ..........................................Start Float
Calendar for scheduling Relationship Lag ........................Predecessor Activity Calendar
Preserve scheduled early and late dates..........................No
Level resources only within activity Total Float.................No
Level Priority 1.................................................Activity Leveling Priority - Ascending
Level all resources..............................................Yes

Advanced
--------
Calculate multiple float paths...................................Yes
Calculate multiple float paths using.............................Total Float
Number of paths to calculate.....................................5

Statistics:
-----------
# Projects.......................................................1
# Activities.....................................................5
# Not Started....................................................5
# In Progress....................................................0
# Completed......................................................0
# Relationships..................................................3
# Activities with Constraint.....................................0

Errors:
-------
Warnings:
---------
Activities without predecessors..................................4
Project: Test Activity: A1000 1
Project: Test Activity: A1010 2
Project: Test Activity: A1020 3
Project: Test Activity: A1030 4

Activities without successors....................................2
Project: Test Activity: A1010 2
Project: Test Activity: A1040 5

Out-of-sequence activities.......................................0

Activities with Actual Dates > Data Date.........................0

Milestone Activities with invalid relationships..................0

Scheduling/Leveling Results:
----------------------------
# Projects Scheduled/Leveled.....................................1
# Activities Scheduled/Leveled...................................5
Data Date........................................................05-Apr-10 12:00 AM
Earliest Early Start Date........................................05-Apr-10 08:00 AM
Latest Early Finish Date.........................................17-Apr-10 05:00 PM
Number of float paths............................................0
Exceptions:
-----------
Critical Activities..............................................4
Project: Test Activity: A1000 1
Project: Test Activity: A1020 3
Project: Test Activity: A1030 4
Project: Test Activity: A1040 5

Activities with unsatisfied constraints..........................0

Activities with unsatisfied relationships........................0

Activities with external dates...................................0

Activities delayed due to predecessor delay......................1
Project: Test Activity: A1040 5

Activities delayed due to resource leveling......................2
Project: Test Activity: A1020 3
Project: Test Activity: A1030 4

Activities that cannot be leveled................................1
Project: Test Activity: A1010 2

Activities that cannot be leveled backward.......................1
Project: Test Activity: A1010 2

Activities that are not on any float paths.......................4
Project: Test Activity: A1010 2
Project: Test Activity: A1020 3
Project: Test Activity: A1030 4
Project: Test Activity: A1040 5
Rafael Davila
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Catalan,

Usually I subscribe for the fights the very same day directly through the cable box, and this fight I am not going to miss. Cotto fight might be on HBO and in such case it will be for free, this one also I am not to miss.

Rodel,

As you can see we are tolerant to change direction in the discussion, if you look at the title it was supposed to bring controversy in another theme I was hoping to be even more controversial.

Anoon, Catalan, Mike Testro and the others at times calm us down with unexpected comments I love and appreciate.

Best Regards,
Rafael
R. Catalan
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Rafael & Rodel,

Cool down guys, you’ve overtaken me in taking post #139.

Hey Rafael, have you subscribe to Mayweather vs Mosley fight this May 1? I’m very excited to see this fight. The same with Cotto vs Foreman.

Best regards,
R. Catalan
R. Catalan
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Rodel,

I am now using the post # 139 but the issue here concerning resource leveling is not yet reconciled. Maybe you guys can utilize more all your efforts in other threads.

For me, I’m going to defend Primavera and P6 since this is the mostly-used and industry required software in Middle East. Otherwise, will be out of jobs. I wish we’ll have the chance to use the full version of Spider.

I would love to see Vladimir marketing the software in the Middle East.

Best regards,
R. Catalan
Rodel Marasigan
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Rafael,

We just prove why and spider project don’t do it either because it over allocated which is the same as P6 clearly prompted on the log file.

We do the exercise fair and compare apple to apple as per your sample.

If you don’t want to open your eyes, it’s up to you and we respect it. As for the P6 users we still stand P6 have the same result and correctly leveled the resource.

Best Regards,
Rodel
Rafael Davila
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Rodel,

My example shows two computations of float for activity A1010, P6 says it is 10 days which does not makes any sense, if you delay the activity to late bar either over-allocation will happen or the job will be delayed, this breaks the basic rules of resource constraining. On the other hand Spider Project shows 2 days float, the correct value.

Does P6 displays a warning that for activity A1010 the displayed value of float will over-allocate the resource? I doubt it and would like to see such a report.

Best regards,
Rafael
Rodel Marasigan
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Rafael,
We respect what you believed. We know that we cannot change what you insist and that your own opinion. We just proved based on your example that your claimed is wrong. It will not change until it’s proven. We love to know all the bugs we can encounter using P6 to be aware and not to compare. I am not defending P6 here. I just want to resolve the issue by doing the exercise as you requested for other to enlighten what is the result.
Best Regards,
Rodel
Rafael Davila
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THE PROBLEM IS THAT FLOAT AS DISPLAYED BY P6 AFTER RESOURCE LEVELING IS PLAIN WRONG.

As long as float is mentioned in the specs the required software shall be one that shows the correct math.

Definition of float requires it to meet all logic and resource constraints. Showing incorrect float values for resource leveled jobs is wrong. If not available without delaying the job duration in compliance with resource requirements shall not be shown by pretending it is correct.

Best regards,
Rafael
Rodel Marasigan
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Rafael,
Sorry, I’m not sure what you want to portrait.
Again, if the planner/ user read the log file he will understand all information for error, warning, exclusion, out of sequence, not leveled, schedule override… etc…
As you said, it is the responsibility of the planner to correct all those findings. So what’s the problem there?

Best Regards,
Rodel
Rafael Davila
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Rodel,

Here the schedule report is to be submitted with every schedule update and all out-of-sequence as well all resource issues are required to be solved, is a contractual requirement. We are not allowed to submit a schedule that hold the projected finish date by allowing over-allocation, we must either take the steps to get on target or report true projections by allowing the software to show how much off target we are.

I am not sure how this is enforced for jobs where P6 is required, but won’t be surprised if P6 dictates what others shall do as long as many continue with the infatuation with Primavera Products.

Best regards,
Rafael
Rodel Marasigan
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Rafael,

As I said, P6 is doing the same thing. Many options have been removed from P3 to P6 like extending or shorten duration when leveling. I’m not sure if the planner/user is aware of what P3 or P6 response to leveling when they are not reading the result log file. It’s all there what has been leveled, errors & warning, exclusion, number of activities leveled, number of activities wrong sequence or in correct logic etc… I believed most of the user just leveled and never read the report. I always check the report that is why I know what’s happening during the level, schedule, export, import etc...

I suggest all planner/ user to use/ read the log file to check what error or warnings indicated on the log file after executing application to understand what happened after the execution.

Best Regards,
Rodel
Rafael Davila
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Rodel,

I am not sure about P6, but for years before using SureTrak we used P3. P3 had the option to select for resource leveling not to allow the leveling routine to extend project duration and stop applying true resource constraining to these resources or you could select for resource constraining routine to respect resource requirement and allow the software to show true schedule projection.

As we all know some settings that allow you to bypass schedule logic are considered “bad practice”. Allowing the software to level some resources and others not is bad practice, it hides logic, and it hides the fact that if some resource issues are not solved then the schedule due date will not be met. If the software cannot provide you with true resource constrained float then the problem becomes even greater.

Spider is not like P6 it will not perform the leveling routine allowing over-allocation of course if need be it will delay project completion and then it is the responsibility of the scheduler to work it out. It will correctly display over-allocations before running the resource leveling routine. If resource leveling is impossible like if you have an acitivity asking for more of the available for the resource it will delay the activity and warn you that the resource leveling missing the requirement.

Best regards,
Rafael
Rodel Marasigan
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Rafael,

I believed P6 is the same not leveling over allocated resource. Maybe the only difference is Spider Project prompt the user that cannot level due to over allocated while P6 prompt the user by the way of log file.
As I mention earlier, I figure it out when I over allocated all resources and P6 did nothing. When I check the log file it mention not leveled for every activity having over allocated resource.
Rafael Davila
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Rodel,

I do not know how to force Spider Project to allow for over allocation under a functionality that shall work. Resource constraining in Spider Project always respect the mathematical requirements for the model to schedule within available resources. Either it will tell you it is impossible, not uncommon within material resources, a functionality I believe is possible P6 does not have or it will delay project completion respecting the validity of the resource constraining algorithm, otherwise it should be called resource over-allocation, something that does not solve the issue and that should not be allowed by any CPM specification.

Is kind of similar to when there is an out-of-sequence occurrence, the only way to solve it is by fixing logic, not by an automated procedure that pretends to solve it as if a universally correct procedure. Over-allocations must be solved by making available more resources, by allowing the schedule to slip, yes that the job is projected to be late can be a true model projection, or by any other appropriate mean. Leaving over-allocations unsolved is wrong and should not be allowed.

If your software artificially constraint project end date you will not be able to see the logic within your schedule, you got to let the software to show the delay and from here you start making the adjustments.

Do your specs allow for resource overallocation happen without being cleared?

Best regards,
Rafael
Rodel Marasigan
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Vladimir,
I know what do you mean but this is not included on this exercise. We only comparing apple to apple as per example. Maybe we can demonstrate another problem illustrating this issue using same comparison again. I’m happy to know what bugs really reside on P6 so all users/planner become aware.

Rafael,
I used only same comparison with the sample that you illustrate. As I said (if you read my post) P6 did not touch or did not levelled Task 2 for having over allocated loading which is indicated on the log file. (A1010 not level using forward, A1010 not level using backward). On the figure comparison (apple to apple) using same resource loading it show exactly the same including resource histogram.

I suggest that if possible try overloading resource on Task 2 and let us know what will be the result. It’s very interesting to know if your tool will come up different result.

Best Regards,
Rodel
Rodel Marasigan
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Vladimir,
I agree with you that P6 will not physically prompt the user if the resource is overloaded. The user needs to check the histogram or unit/time to know the reason why? I figure it out when I overload all resources and P6 done nothing. It did not level resource and everything is the same. Like what you said every package have differences and I think this one is missing in P6 (prompting the user why it is not levelling). The fastest way to check the error is by reading the log file when selected Log to file option. It mentions which activity cannot be levelled.

In regards to 50% assignment as I mention on other post (using multiple calendar), P6 responded based on calendar and hours per time period settings.
If you need 50% per resource then calendar must set on each resource. (ex: R1[a]=8:00AM-12:PM and R1[b]=12:00PM-04:00PM) within 8hrs setting at hour per time period.

Best Regards,
Rodel
Rodel,
I will see this warning only looking to the specific resource histogram. In the projects with hundreds resources assigned it is impossible to check the histograms of all resources.
I still don’t understand why the float become larger for overallocated resource.
I would expect that the package will warn that the levelling is impossible without adding additional resources to resource pool because the quantity of resources assigned to the single activity exceeds available quantity. I think that it is logical.

Actually I don’t approve assigning hours without assigning quantities. In this case it is not possible to assign two resource units with 50% workload if the quantity is not specified.

Best Regards,
Vladimir
Rodel Marasigan
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Vladimir,
P6 actually warned that resource is overloaded. (see below) You’re correct that the cause of 13.33hr/d is due to duration change. The behaviour of P6 is depends on the settings. The user can control Primavera’s behaviour on settings available.
P6 Figure5

On this exercise Duration type is set to Fixed Duration & Unit meaning Unit/Time is variable but if the setting is Fixed Duration and Unit/Time or Fixed Unit/Time then the unit will automatically change and become variable.

Best Regards,
Rodel
Dear Rodel,
please explain why
1) P6 does not warn about resource overload when resource is assigned 13h/day and calculated resource-constrained schedule?
2) the float is larger when resource requirements are higher?
I am intrigued by these results and want to play with P6 myself. I suspect that 13 hours/day may appear automatically if to shorten activity duration from 5 to 3 without reassigning resources, isn’t it? Very strange setting.

Spider Project would warn that you need additional units of resource R2 and will refuse to level the project.

Please explain.

Best Regards,
Vladimir
Rafael Davila
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Anoon,

You can download the sample file from the following link.

http://rapidshare.com/files/375350976/Test.xer

Even if you cannot figure it out about the parameters chosen it is enough proof if only a single activity displays wrong value of float. Also review my posting #120 were the occurrence is pointed out.

You can also go back at Spider float values as per my posting no 111. They are different therefore either one must be wrong. Well it is P6 who is wrong as a simple analysis of the figure shown in posting #120 proves it, P6 is displaying wrong float for activity A1010, is quite simple.

Best regards,
Rafael
Anoon Iimos
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Hi Mimoune,

Actually, right now, I’m near your country.

Anyway, I supposed the intention is to do "resource levelling" so as to get the minimum duration possible.

This is considering that you will be using resource calendars as well as activities calendars which are not necessarily the same or consistent.

And I guess Vladimir is offering a solution, why not try it Mimoune?

Hi Rafael,

I believe that you cannot prove it with just your presentation below and you did not elaborate with the parameters that you had used (or used by someone else).

Best regards

Rafael Davila
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The value of float for activity A1010 displayed by P6 is wrong under the prioritization rules that set up the sequence of the resource leveled schedule. Under this sequence if you delay the finish of this activity by 10 days it will occur at the same time with activity A1030, this means P6 is not in compliance with the requirement for the algorithm to respect constraints, is breaking the premise that no matter what you have set as rules the result must be correct

RC2 P6

Note that under resource leveling the real float bar cannot always be considered continuous, you can delay the activity to happen at the late bar position and satisfy the resource constraint requirements but not necessarily if in between, this means there are also limitations on whether you can increase the duration or not of the activity.

Best regards,
Rafael
mimoune djouallah
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pfffff sorry Anoon to hear that, anyway what are you doing in Philippine anyway !

Just to prove that i am really open mind, i think i was wrong, actually P6, give correct values for resource leveling including total float, but there is a hick.

in the case of a simple schedule ( 4 activities) P6, give a solutions which is so far from the optimum solutions, that automatically a normal joe will conclude it is wrong. but in reality( mathematical meaning) it is a correct solution in the sens that it satisfy the conditions( both links and resource availability)but unfortunately it increase project duration.

best regards
Mimoune
Anoon Iimos
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Dear All,

Sorry if I cannot really answer well all your clarifications as I was just fired (anyway, no worries, I’m used to it).

As regards using exactly the same calendars for activities and resource, well I never said that, but I supposed there would be no problem with resource levelling if this is the case.

The problem I believed will occur (with resource levelling) is when using different or various calendars for activities and resources.

How can you make a coordinated resource levelling when using various calendars? For me, this is impossible, but I’m not sure of course (as my mind is just ordinary).

And I’m really curious about Vladimir’s and Rafael’s solution to this, which up to now, all I hear is something better than sales talk.

Best regards

mimoune djouallah
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HI Anoon

i hope you are kidding me, there is no conspiracy here, i have no affiliation with Rafael, but i do have an advantage, which is i am a junior, it means, i don’t have any strong idea about any method, i am just learning, I don’t care really if P6 is better or not comparing to others packages. but i do care to have a correct results.

yes, as A P3 user, i set many rules for priority of resource leveling, it depends, total float, early start, etc, sometimes i just fellow the intuition of the construction manager, he wants to put more resources on a particular task, after all he is the responsible not me.

having saying that, and from a guy who is aware, there is no exact solutions for the problems of resource leveling, but rather many approach to solve the problem and give a good solution to satisfy both resource availability and logic constraints. all those rules are for getting better solution, let’s say optimizing the solutions. but no matter what you have set as rules the result must be correct.


i expect from the software to give me a correct solution, perhaps far from optimum, but nevertheless correct (it satisfy the conditions), otherwise it is an issue and should be declared by the vendor.

and for testing the four activities schedule, no need to check another package, manual calculation, can spot, that there is something not ok.

best regards
Mimoune
Rafael Davila
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I would like to highlight that in occasions, especially with simple jobs, Standard resource leveling algorithm in Spider is still Optimal. Standard resource leveling algorithm in Spider yields similar result to other software.

I agree with Vladimir that resource leveling should look for minimum job duration, if not you can level your resource using Rafael Algorithm, is very simple just set all activities in tandem, only one activity happening on a given time and here you got a feasible solution with regard to the issue of resource availability.

For your convenience I uploaded in Rapidshare the xer file for the second sample job, if interested you can download it from the following link.

http://rapidshare.com/files/375350976/Test.xer

I have read some literature in search of Resource Critical Path, some do not mention the need for resource leveling on the backward pass while other papers by Vladimir Liberzon mention the need. Is possible that P6 algorithm is based on other methodology and this is why some results are wrong pretending they are right, who knows.

No matter what we must be critical and do as Anoon, question it until we make it clear.

That mimoune got it on the spot does not means he supplied me with the sample job, I believe he mentioned other occasions P6 yields strange results for float, he noticed the behavior in real life jobs and not only in particular sample jobs, he knew about this way before the issue was raised on this thread.

Best regards,
Rafael
Hi Anoon,
please clarify what may be changed with the schedule and floats if to select task or resource dependent and all activities and resources have the same calendars.
I did not try to say anything about Spider but of course all restrictions shall be taken into account during scheduling (levelling) process. No one restriction governs - all shall be satisfied.
I did not understand if you tried Rafael example or not?
Resource levelling does not require tailoring - it shall create the project schedule based on the same data and satisfying all resource limitations. Besides the shortest resource constrained schedule means better resource utilization.

Best Regards,
Vladimir
Anoon Iimos
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Hi Mimoune,

I suspect that you are the one who supplied Rafael with that sample?

"notice here, i did not change any default rule"

As you had mentioned, of course this will create some discrepancy as you are supposed to handle "resource levelling".

In my opinion, your settings and options are supposed to be tailored to handle resource levelling as well.

How can you level Resources if your activities were set to "Task Dependent"? I supposed your program will follow task dependencies and not resource dependencies.

Now, I guess Vladimir and Rafael is saying that Spider can handle both dependencies (Task and Resource), at the same time when levelling resources, but I’m not really sure if which one governs (or they did not tell us) when making adjustments in order to get the minimum duration possible?

Best regards


mimoune djouallah
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hi all

that’s far what I got from experimenting in Primavera p6.
as far as you put only activities with one resources and without links, P6 handle well, and it give you the right Total float, but if you start with only four activities, and assigning two resources and some links, it level correctly the activities (max usage not reached) but you will get inaccurate total float, sometimes even some negative one.

notice here, i did not change any default rule

i hope i am wrong in my calculations, but it is a a very serious matter, we call this bug, or even worst, defective by design.

best regards

Mimoune
Anoon Iimos
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Hi Vladimir,

To clarify the statement of Rafael that P6 displays wrong float(s) (whatever it is Free Float or Total float) after resource levelling - That is not true (at least from my own trials).

Hi Rafael,

You are not making real comparisons. I guess you are just finding faults, but please be fair. You need to put the two programs in exactly the same settings and options (if that is possible) and run the schedule or resource levelling, so that we shall know which one is a copy of what?

Oh by the way, I don’t know if P6 has the capability to show Resource Bars.

Best regards
Rafael Davila
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Anoon,

I just realized that the prior example sent to me is in disagreement because it was set up to work under optimization an automatic resource leveling option that consistently yields shorter job duration in Spider, I was comparing apples with oranges. The following is a screen capture of the resource leveling results using the previous sample job using Spider optimization.

RC1 Spider

I am using another example of the small project where all activities are linked only with Finish milestone. The float of activity 2 (ID:A1010) is rather strange. Please next after you will find the computations of float that Spider yields, these are the correct values.

RC2 P6

RC2 Spider

Sorry for any inconveniences, at times determining where some software will display wrong values for float is not easy for me when I do not have the software. The P6 files were issued on the run with the help of someone not in my office, this is making it harder to prove the point but does not invalidate it.

Best regards,
Rafael
Rafael Davila
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Anoon and all I got the sample P6 file in xer format so any of you with P6 can work it out please download from the following link.

http://rapidshare.com/files/375131764/Example.xer
Hi Anoon,
please clarify what is not true?
Best Regards,
Vladimir
Anoon Iimos
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Rafael,

Yes, I stand by my statement. For P6 (6.1), what you said is not true. For P3, from my trial, yes you are right.

Best regards
Rafael Davila
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Anoon,

-“What is most important, Activity logic or Resource Logic?”

Both are relevant, both must be taken into consideration.

Remember the sample job is just an example but you can add a Start event and a Finish event as for you not to leave any open end but only at the start event and finish event.

Why are you to model a logic link between two activities when there is no logic link, this prevents the model to be a good representation of the network as the resource dependencies are not fixed and can vary as the schedule moves. This unreal links are known as "soft links" and are even banned by some of our CPM specs, the same specs that require you to use resource loading with a software of their choosing incapable of displaying true available Float after resource leveling, perhaps with the intention to steal away from you not only available float but unavailable float as well.

By the way, thanks for your honesty about what is displaying your model. If does not agree with my statement it shall be disclosed, PP is about exposing the truth for the benefit of all members.

Best regards,
Rafael
Anoon Iimos
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Hi Rafael,

Yes I can see it, but it seems that the logic is discontinuous (i.e. 2nd and third activity has no relationship). I guess the erroneous floats were caused by erroneous logics. Please try to connect them all with FS only or SS only and see the results.

As we are considering resource dependencies, logic must be established by the shared resource or resources, which means that settings shall be all focused on the shared resource or resources.

You can forget the logic that you had established for your activities.

This is what I’m trying to asked on Vladimir in previous or other threads:

What is most important, Activity logic or Resource Logic?

And he said both, but he is defining Activities or Tasks first (in terms of logic).

So in case of conflicts, which logic governs during resource levelling?

Best regards
Rafael Davila
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Anoon,

Sorry but here cheating is a fact of life, we even have criminals, this is no Disney World.

Many of us find it unfair when the Owner steals away from you your own planning tool and even go further to steal away available float from your own planning as we perceive float as a buffer necessary to avoid delaying your job, if stolen from you then it will no longer be available. The truth is some designers are a disaster and must issue hundreds of revisions to their drawings, and then they delay the job and pretend the Contractor to pay for their error. Under these circumstances we find it morally acceptable and even good business practice from the Contractors point of view to hide some float. Imagine when the software shows available float and it does not exists, some Owners will even try to steal from you unavailable float, is insane.

The wrong computations for float is a fact in Primavera SureTack, in Primavera P3 as well as in MS Project. We observed P6 float calculations were wrong as I told you but cannot recall the version because I never paid attention to it, it could have been 6.0. In any case because of the file sent to me I suspect newer versions of P6 are still displaying some wrong values for float. I was not exaggerating, in any case software developers that display wrong float values and with the knowledge this is so do not warn the user are cheating their own clients.

On the displayed Screen Capture all logic is shown, there are two resources and only two FS links. Is necessary for you to include the links as shown and resource usage as shown, otherwise the model is other.

I do not believe I will ever buy a P6 license but perhaps will be able to try it again on the computer of someone with the license.

Let’s see if I can get a copy of the file so I can make it available for the use of all by posting it on Rapidshare.

Best regards,
Rafael
Anoon Iimos
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Hi Rafael,

I don’t understand about strategies or how do you present your schedules. I’m just a scheduler (or just a follower for the good side - and it doesn’t include cheating).

Going back to float calculations or results after resource levelling, for now I would say that what you were saying about P6 is not true, but that’s understandable as you were just exagerating and not really trying it yourself (so I can forgive you with that). And please note, the version I used is 6.1 (not the latest one), and further note that the trial is just limited to 4 activities. So again, beyond that, I don’t know.

I just hope that someday you will really try it yourself and may we hear your expert and honest opinion about it (without the sales talk).

Best regards

p.s. Sorry, I suspect that the results of your sample or your sample was inflicted by not so logical - logic.
Rafael Davila
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Anoon,

Of course you can tweak or cheat with the program, especially when the tool is no longer a management tool but a tool to be used as a claim tool.

Some Contractors here create a CPM that should favor their claims and use it just for these purposes and manage the job using "experience", I call it "perception" a concept management schools and behaviorist scientist study as it can be deceiving. Others, I would say the majority, create two versions, one that hides float to the Owner and favors his claims and another that represents his dynamic planning. Is a well known secret.

Best regards,
Rafael
Anoon Iimos
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Hi Rafael,

As you know it, you can tweak or cheat with the program (GIGO). I supposed these algorithms don’t have the capabilities to lie.

Oh by the way, with the four (4) activities only the third and fourth activities moved when I run/level the schedule, the first and second remained in place and displayed no resource in the spreadsheet (but they were assigned as well).

Best regards
Rafael Davila
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Anoon,

I did not worked the sample job but because I do not have P6. Note is using 2 resources, is not a single resource. Still simple enough for illustration purposes.

Activities

I agree with you a responsible software developer that knows some values as displayed are wrong should warn the user in a visible way, I would go as to say under these circumstances this knowledge should invalidate any disclaimer because is of his knowledge and hiding the fact is intentional. But jurisprudence is a dynamic thing; perhaps eventually under certain circumstances this protection will be unlocked.

Best regards,
Rafael
Anoon Iimos
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Hi Rafael,

I believe that the screenshot that you are showing now is from P6. However, I don’t know what settings you had used (or used by someone who had sent you the sample), for this example.

P6 has lots of options, so finding the right option alone can become difficult for the not so experienced (like ME).

I tried it again with four activities sharing the same (single) resource and run / level it.

It shows zero floats (Total, Free, Remaining) for the first two activities, and negative floats for the third and fourth activity (for the remaining float only, the rest all zeros).

And please note: When displaying resource usage spreadsheet, I for one believe that it is calculating accurately (at least with the settings that I had used for the 4 activities). Beyond that (or with more activities and options), I don’t know or not sure.

Best regards

p.s. well, I had the feeling as well that if there are some conflicts, P6 just ignore it (or will not react). I think it is much better if the Program will show some warning or hint/help like the one done by excel when it cannot read the formula. Again, I’m not sure of this, I’m just a civil engineer and not a computer expert.
Rafael Davila
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Posts: 5073
P6 Example

Anoon,

You were correct in your posting #73, the 2 activities sample job cannot illustrate the erroneous calculation for total float done by P6, a larger 4 activities job is needed. Your way of debating the issue is the correct way, and I thank you for being one of the very few who took the time to verify the sample job and call it to my attention.

I just got in my e-mail a sample job using a sample schedule of 4 activities in parallel, it still show wrong total float calculations. I was told that because of the way P6 calculates total float the 2 activities example is not good to illustrate P6 wrong calculation of total float. Seems lik we need a 4 activities job to illustrate that total floats are not calculated properly by P6. Still with P6 you never know when calculated floats are right or wrong.

Remember I do not have P6, this is from a screen capture received by e-mail, therefore with P6 this is as far as I can go, but should be enough. You can try it yourself and let us know about your findings. Note the sample is based on 4 activities and 2 resources plus some link between activities, this might be said to be closer to real life jobs, where schedules use more than 2 activities and 2 resources.

I do not have P6 and already discarded Primavera SureTrak because is incompatible with Windows 7 and unacceptably slow using a virtual machine therefore in the future I will use the 4 activities sample job as provided, until P6 and others can get it right with this 4 activities sample job.

Best regards,
Rafael
Thanks Rodel,
I am glad that we have the same oppinion.
I understood that Rafael is disappointed by his Clients that require the use of the certain software that he does not like at all. It looks like the common practice in his country.
Best Regards,
Vladimir
Samer Zawaydeh
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Thank you Vladimir for the links.

With kind regards,

Samer
Rodel Marasigan
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Thanks Vladimir,
Certainly agree and I believe that’s the practice here in Australia. We respect each company’s capability.

With Kind Regards,
Rodel
Rodel,
I don’t mean you personally.
I wrote about general Client - Contractor relationships.
I think that the Client may require certain forms (formats) for the schedule submittals, what level of details shall the schedule include, but not what tools and methodologies to use for Contractor construction management.
Do you agree?

Best Regards,
Vladimir
Samer,
If you are interested in the methodologies that we use and promote look at the publications at http://www.spiderproject.ru/publ_e.php#eng and http://www.sdpmworld.com/
Soon I will add there new presentations that will be made for PMI Great Lakes Chapter, PMI COS Conference, and Risk Management conference in Singapore. So don’t forget to return.

If you want to learn the tool (I mean Spider Project) you can download free Demo from http://www.spiderproject.ru/demo_e.php

Demo is almost full functional (except some export/import capabilities) but has 40 activities per project restriction. It is not necessary to buy if you want just to learn the tool.

Best Regards,
Vladimir
Rodel Marasigan
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Vladimir,

Thank you for your clarification. My apology if my wordings are not clear. We don’t dictates; we follow what is required and were agreed by the top management.

With Kinds Regards,
Rodel
Samer Zawaydeh
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Posts: 1664
Dear Vladimir,

It is ok, I will end up buying the software in the future. This is what usually happens with all companies if you want to learn the tool.

I had to ask. I think that you might be talking about new methodologies and Project Management issues. This you can publish and sell with International Book Publishers. It becomes easiers and more accessible to everyone at reasonable prices.

With kind regards,

Samer
Rodel,
maybe I did not understand you correctly.

You wrote:
“Clients or stakeholders always looking for systems that compatible to their system as much as possible so the data exchange and communications will much easier.” (If we use different systems from each other how are we able to communicate?)

From this I understood that you advocates the right of the Client to dictate to Contractors what project management tools shall be used.

I tried to explain that it may lead to worse project management and may create huge problems to Contractor’s management teams, that the Client and the Contractor have different requirements to the schedule model, etc. I think that the Client may require certain formats for the data that are submitted but has no rights to dictate what tools the Contractor shall use to manage its resources. At least it is not smart.

I am sorry if it was not clear, English is not my native language.

Best Regards,
Vladimir
Rodel Marasigan
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Vladimir,

I have no objection on any management tools, impact we used those tools. We have integrated System that talk to each other. (like Prism, SAP, Estimating module, Risk Analysis module using Monte Carlo simulation and etc…)

Our company have own IT analyst/ developer/ software programmer dedicated to continues improvement of PMS, communications and maintaining the integrated system.

I’m not sure what you are trying to portray here.

Best Regards,
Rodel
I am sorry, Samer.
Most our clients speak Russian and the documents that are created are in Russian.
Besides most companies do not like to share their internal standards.
I will think what can be done and will write to you directly.
Best Regards,
Vladimir