calculate summary start and finish using pert anayst

S

SunbirdII

need to automatically set start and finish of summary tasks based on duration
and and start of project date. Is PERT Tool valid to use?
 
J

JulieS

Hi SunbirdII,

The start and finish dates of summary tasks are set by the start and
finish of the subtasks. The start of a summary task is the start of the
earliest subtask and the finish is the finish of the latest of the
subtasks.

PERT is a method of calculating task duration based upon Optimistic,
Pessimistic and Most Likely Durations of tasks. You may use PERT for the
subtasks, but the summary task duration is automatically calculated as
the amount of working time (as defined on the project calendar) from the
start of the earliest subtask to the finish to the latest of the
subtasks.

I hope this helps. Let us know how you get along.

Julie
 
S

SunBird II

Hi Julies;
Thanks Much for your response, however perhaps I did not fully explain as
follows:

1 Requirement is to be able to build template so that project manager only
enter the project start date and enter number of days or duration for each
summary task and have Projects calculate start and finish times of each
summary task and end date of project.

I am able to use PERT anaylst tool to enter duration of each sumarry task
however have not figured out how to move the duration enter into the PERT
form to calculate calendar dates. Do you think this is doable?

Thanks
SunBird II
 
J

JulieS

Hi SunBird II,

If you create the template with the tasks linked in a logical manner and
without having manually entered start and finish dates, you should be
able to achieve what you are seeking. A project manager will create a
new project based upon the template, set the project start date, modify
durations as needed, which will change the task's start and finish date,
and the project end date will be calculated.

I am wondering if we are using the term "summary task" in different
ways, however. In the MS Project world a summary task is a task that
has subtasks and the start and finish are calculated as I noted in the
previous post. If a project manager changes the durations of the
subtasks, based upon the links, lead, lag between the subtask, the
duration of the summary task will change.

As to PERT Analysis: On the PERT Analysis toolbar there are several
buttons that should help. If you are attempting to use PERT for all
tasks, you may want to use the button that displays the PERT Entry Sheet
view. That will give you fields for Optimistic, Expected, and
Pessimistic Durations. Once you have entered the data, click the
Calculate PERT button and it should calculate (or recalculate) the
duration.

I hope this helps. Let us know how you get along.

Julie
 
S

Steve House [Project MVP]

That's exactly the way Project functions EXCEPT that summary task durations
are read-only fields calculated based on the durations of their child
subtasks and will not accept direct user input. The duration of a summary
is the length of time between when its earliest starting child starts and
its latest finishing child ends. So when you list each summary's children,
set up the dependency links between them, and enter their durations, the
summary task's duration will be calculated. The start milestone links to
the first subtask in the first summary. The last task in each summary links
to the first task of the next one on line and so forth until you get to the
end of the project. Entering just the Project Start date will result in all
the other dates in the project being calculated.
 
S

SunBird II

First of all "Thank You Both - Julie S. and Steve House" ...
You both also confirm my understanding of the logic or operation of summary
and child row however - addressing back to Steve - the linking of the first
child of each summary thru the last child of that summary then linked to the
subsequent summaries row first child..and so on until the last summary row
and thru to its last child row. Questions
1- unless the last child row of the last summary row is connect to something
link the project end date.. how would the end date be calcuated ?
2- Maybe I should have made this statement at the begining of this posting,
as follows.
Today the project users launch a Excel Spread sheet to manage their projects
and as part of the evaluation, planning to convert their Excel Spread sheets
into MS Projects there are several templates such as a project manager
schedule sheet that has a Excel calcuation which has embedded the duration of
each summary task or phase already plugged into the sheet. Therefore once
the project manager launches his Excel Spread sheet he simply enteres in the
planned start date and the spread sheet calculates the planned project finish
date(irrespective of holidays and weekends), as well as the summary row dates.

My attempted feasability solution for converting to MS Projects is the
process which you have just provided answer too - - except for the use of the
last part include in point one above. How do we arrive at the Finish date if
the last link being the last child of the last summary row is not connected
to anything?

Thanks Very Much
SunBird II
 
S

SunBird II

Hi JuileS;

Thanks;
I had tried the PERT Entry Sheet however did not find that calculate PERT
button in order to do re-calculate. Is the calculate PERT button on the PERT
Entry Sheet or it is the PERT calculator????"

Also holding for Steve's response concerning where to connect or if I have
to connect the last link of the last summary row's last sub summary row.. in
order that we can have the automation configuration of start / finish dates
for summary rows.. Good Discussion.

Thanks;
SunBird II
 
S

Steve House [Project MVP]

The Project finish date is the date when the latest finishing task in the
project is done. It is good practice and contributes to clarity to have a
"Start" milestone at the begining of the project and a "Finish" milestone at
the end. Another rule of thumb is that all subtasks except for those
milestones will have both predecessor and succesor links. This results in
one or more chains of tasks flowing through the project and all subtasks are
a part of one of more chains. If a task has no other predecessor, the
project start milestone is its predecessor. If a task has no other
successor, the project finish milestone is its successor. Thus the project
finish date is the date displayed for the finish milestone, also the date
that the longest chain of events in the project finishes. This chain of
events is also the "Critical Path" by definition. Note that I am referring
to subtasks also sometimes called "performance tasks" here, observable
physical activities in other words, here. Summary tasks are simply
artifacts inserted for reporting and organizational purposes - in a well
designed project plan you could remove all the summary lines while leaving
all the subtasks in place and the schedule wouldn't change, all the work of
the project would still get done.

Be careful about using the terms "first task" and "last task" - I'm not
talking necessarily about the first in the list and the last in the list,
I'm talking about the first to start and the last to finish.
 
S

SunBird II

Thanks that works. However the point that does not seem to be working as
planned is have a predetermined duration fixed between each summary task
therefore when the start project date is entered into the this template all
the planned start and finish dates will be automatically generated based on
the duration of each group of summary task. Need your feedback...Thanks

Steve House said:
The Project finish date is the date when the latest finishing task in the
project is done. It is good practice and contributes to clarity to have a
"Start" milestone at the begining of the project and a "Finish" milestone at
the end. Another rule of thumb is that all subtasks except for those
milestones will have both predecessor and succesor links. This results in
one or more chains of tasks flowing through the project and all subtasks are
a part of one of more chains. If a task has no other predecessor, the
project start milestone is its predecessor. If a task has no other
successor, the project finish milestone is its successor. Thus the project
finish date is the date displayed for the finish milestone, also the date
that the longest chain of events in the project finishes. This chain of
events is also the "Critical Path" by definition. Note that I am referring
to subtasks also sometimes called "performance tasks" here, observable
physical activities in other words, here. Summary tasks are simply
artifacts inserted for reporting and organizational purposes - in a well
designed project plan you could remove all the summary lines while leaving
all the subtasks in place and the schedule wouldn't change, all the work of
the project would still get done.

Be careful about using the terms "first task" and "last task" - I'm not
talking necessarily about the first in the list and the last in the list,
I'm talking about the first to start and the last to finish.


--
Steve House [Project MVP]
MS Project Trainer & Consultant
Visit http://www.mvps.org/project/faqs.htm for the FAQs


SunBird II said:
First of all "Thank You Both - Julie S. and Steve House" ...
You both also confirm my understanding of the logic or operation of
summary
and child row however - addressing back to Steve - the linking of the
first
child of each summary thru the last child of that summary then linked to
the
subsequent summaries row first child..and so on until the last summary row
and thru to its last child row. Questions
1- unless the last child row of the last summary row is connect to
something
link the project end date.. how would the end date be calcuated ?
2- Maybe I should have made this statement at the begining of this
posting,
as follows.
Today the project users launch a Excel Spread sheet to manage their
projects
and as part of the evaluation, planning to convert their Excel Spread
sheets
into MS Projects there are several templates such as a project manager
schedule sheet that has a Excel calcuation which has embedded the duration
of
each summary task or phase already plugged into the sheet. Therefore once
the project manager launches his Excel Spread sheet he simply enteres in
the
planned start date and the spread sheet calculates the planned project
finish
date(irrespective of holidays and weekends), as well as the summary row
dates.

My attempted feasability solution for converting to MS Projects is the
process which you have just provided answer too - - except for the use of
the
last part include in point one above. How do we arrive at the Finish date
if
the last link being the last child of the last summary row is not
connected
to anything?

Thanks Very Much
SunBird II
 
M

Mike Glen

Hi SunBird II,

I don't know how many people you need to tell you or how many times, but the
duration of a Summary Task is not enterable! :) You cannot enter any data
against a summary task as it is Project's job to do that. Your PM will have
to enter the new project start date and then change any of the individual
task durations to meet the new requirement. Project cannot guess how you
want individual task durations to be apportioned - it is the job of the PM
to do that. Then Project will do its job and tell the PM what the feasible
finish date is based on the data they've entered. The only date you enter
into Propject should be the start date. Then the durations, logic links and
assignments of resources, then Project will calculate the dates for you. If
the finish date is not what the PM wanted, then he will have to change
individual task durations until the finish date is acceptable. That's how
Project works. :)


Mike Glen
Project MVP




SunBird said:
Thanks that works. However the point that does not seem to be working
as planned is have a predetermined duration fixed between each
summary task therefore when the start project date is entered into
the this template all the planned start and finish dates will be
automatically generated based on the duration of each group of
summary task. Need your feedback...Thanks

Steve House said:
The Project finish date is the date when the latest finishing task
in the project is done. It is good practice and contributes to
clarity to have a "Start" milestone at the begining of the project
and a "Finish" milestone at the end. Another rule of thumb is that
all subtasks except for those milestones will have both predecessor
and succesor links. This results in one or more chains of tasks
flowing through the project and all subtasks are a part of one of
more chains. If a task has no other predecessor, the project start
milestone is its predecessor. If a task has no other successor, the
project finish milestone is its successor. Thus the project finish
date is the date displayed for the finish milestone, also the date
that the longest chain of events in the project finishes. This
chain of events is also the "Critical Path" by definition. Note
that I am referring to subtasks also sometimes called "performance
tasks" here, observable physical activities in other words, here.
Summary tasks are simply artifacts inserted for reporting and
organizational purposes - in a well designed project plan you could
remove all the summary lines while leaving all the subtasks in place
and the schedule wouldn't change, all the work of the project would
still get done.

Be careful about using the terms "first task" and "last task" - I'm
not talking necessarily about the first in the list and the last in
the list, I'm talking about the first to start and the last to
finish.


--
Steve House [Project MVP]
MS Project Trainer & Consultant
Visit http://www.mvps.org/project/faqs.htm for the FAQs


SunBird II said:
First of all "Thank You Both - Julie S. and Steve House" ...
You both also confirm my understanding of the logic or operation of
summary
and child row however - addressing back to Steve - the linking of
the first
child of each summary thru the last child of that summary then
linked to the
subsequent summaries row first child..and so on until the last
summary row and thru to its last child row. Questions
1- unless the last child row of the last summary row is connect to
something
link the project end date.. how would the end date be calcuated ?
2- Maybe I should have made this statement at the begining of this
posting,
as follows.
Today the project users launch a Excel Spread sheet to manage their
projects
and as part of the evaluation, planning to convert their Excel
Spread sheets
into MS Projects there are several templates such as a project
manager schedule sheet that has a Excel calcuation which has
embedded the duration of
each summary task or phase already plugged into the sheet.
Therefore once the project manager launches his Excel Spread sheet
he simply enteres in the
planned start date and the spread sheet calculates the planned
project finish
date(irrespective of holidays and weekends), as well as the summary
row dates.

My attempted feasability solution for converting to MS Projects is
the process which you have just provided answer too - - except for
the use of the
last part include in point one above. How do we arrive at the
Finish date if
the last link being the last child of the last summary row is not
connected
to anything?

Thanks Very Much
SunBird II

:

need to automatically set start and finish of summary tasks based
on duration
and and start of project date. Is PERT Tool valid to use?
 
S

SunBird II

I'll turn down my hearing aid:)
Yes I understand that the summary task is not a manual change by the pm*)
what I trying to understand if when we talk about duration, which the task
summary is based on. Can we manually configure the duration as say building a
template. The the project coordinator would house a series of project
templates with different durations configured as per catagory of project
assigments. The the pm would insert the project start date and the template
would now calcuate the summary start and finish dates. When the pm excutes
the task and does the tasks update this would be done in a column called
Actual Start and Actual Finish. Did I make it thru the clouds that I
created:?
 
S

Steve House

You CANNOT "manually configure" the duration for a summary task.
Period. No exceptions. A task is not a summary until it has children -
until then, it just another task and accepts entries normally. But when
children are added and indented under it to make it into a summary, its
duration is calculated based on the children's durations and their start
and end dates and anything that was previously input is over-ridden and
replaced by the calculated values. A SUMMARY TASK IS NOT A REAL TASK -
IT IS ONLY A REPORT ROLLING UP INFORMATION ABOUT ITS CHILDREN and the
only way to change what you see as the start, duration, and finish of a
summary task is by revising the information about one or more of its
subtasks.
 
M

Mike Glen

Hi Sunbird II.

There is nothing to stop you creating a series of templates with all the
tasks set with their durations in place. Each one will have its own
Duration. The PM can then pick the one he wants and run the Adjust_Dates
macro to reset the project start date. Is that what you're after?


Mike Glen
Project MVP
 
S

SunBird II

Hey.. Left on 22nd before seeing your response " Thank You 4 Your Patients".
Glad to see we are right on with the conclusion.
1- I configured separate templates, each with different durations for summary.
2- To configure each summary with it's duration I entered the sum of the
duration of each subtask into the first subtask.
i.e. if summary 5 has duration of 8 days with 6 subtask. I entered 7 days in
the first subtask of that group and all subsequent task in that summary were
made 1 day. This gave the total for the summary of 8 days.
Also all links were connected that first subtask of each summary. Subtasks
proceeding and following each summary FS relationship and all subtask with
the summary SS relationship. Once template is made, it's simply a matter of
changing Title from "Template" to Project Name and then going into Project on
the Tool Bar and drop down to change Project Start date. This causes the new
calendar date to propagate throughout the project schedule.
This end user orginally ran projects from Excel Spreedsheets and had
templates with Excel imbedded formula to handle entering Project Start date
one time and have new calendar dates appear.
One of the big benifits of his new Projects Template that we configured, now
gives him real calendar schedules with respect to weekends and respective
holidays. Additionally he can be more gradular in WBS with respect to coring
down to the minutes and seconds of a resource.
Thanks again for your patients as I was talking to myself for awhile and
needed a sounding board for reality check:}
 
S

Steve House [Project MVP]

But that method doesn't really work all the time. Try this ... create a
summary task Sum1 and indent under it two subtasks, Sub1 and Sub2. Make
each subtask 1 day duration. Summary task duration = 1 day. Now link the
two subtasks FS. Summary task duration becomes 2 days. NOW, right click on
the link between the subtasks and add a lag time of 1 week. Summary task
duration will now equal 7 days while the summary task start and end dates
will be 10 calendar days apart.

Minutes and seconds of a resource ???????????? How can any human work
endeavor be measured to such precision? Oh I grant you, you can carry
numbers to as many decimal places you want. But when I was in analytical
chemistry class back in the day, we talked a lot about "empty precision"
meaning measurments resulting in long impressive looking numbers that meant
nothing whatsoever beyond the first or second decimal place. Project work
is human work and you're going to be lucky to have meaningful precisions of
plus or minus 1 day, much less minutes and seconds. Can't imagine a PM
saying to a resource "Joe, you need to start installing that flange gasket
on Tuesday at 10:37:43 am and be done by 11:18:05."
 
S

SunBird II

Hey, I like ur drift. Funny I just stepped out of client's office talking
about the technique of using the 1st subtask after summary to manipulate the
duration and say I used duration of 8 days in summary row which was derived
from 7 days in the 1st subtask...however there were 4 more subtask in the
group. So I divided the five into hrs and mins to equal that 1 day however in
the "Finish Column" it all was the same date...heheh So I see where your
coming from as I just finish having this discussion. Funny thing is not all
companies are at such a gradular level that they care about what order or
when the subtask are accomplished as long as the discipline is adherence to
the duration of the summary. They want to know if they are on target and if
not they want a heads up ahead of time to have the discussion as what is
being done about it. Will give your suggestions a whirl and Thanks Again.
SunBird II
 
S

Steve House [Project MVP]

The link was introduced so the task would occur in sequence to illustate the
point about summary durations - the principle wopuld apply equally well to
sequencing caused by resource leveling.

IMHO it's on the wrong tack to try to preset the duration of a task or
summary task and then force adherence, setting durations by management fiat
and trying to force the work to fit into that inflexibly sized container
that is what someone decided the work "ought" to be do-able in. Duration is
a consequence, not a cause, and is influenced by too many factors to be able
to hand down from Olympus "Waxing Widgets will take us 3 days." The world
isn't that tidy and pretending it is so only gives an illusion of management
control. It is the physical energy required to create the task's
deliverable that is the constant - a hole must be so deep, a wall has X
square feet to paint, a program requires X amount of fixed-length cycles to
execture or so much mental energy for a programmer to create it. Those all
represent work effort, not time., and will different for a given kind of
activity in each project you do it in. Duration for task simply should not
be defined independent of the context in which the speicifc combination of
task and resource perfoming it will be found. Duration is time and the
length of time some requires is a function of both the amount of effort
required and the rate at which the effort is generated and cannot be
predetermined by setting down policy.
 
S

SunBird II

Maybe I should set the environment as I do agree with your pm philosphy in
running projects(ben there done that). However this environment has a very
interesting take on use of MS Project as a tool. Again "Back in The Day"
(<PC) =(Be4PC's:) Projects were often listed with their tasks and subtask on
spread sheets and you had some targets set based on some historical value or
calculated risk factors. Then came VisiCal when PC's hit and you could put
away ur slide rule and erasures:). As pm apps became more sophisticated the
role grew by leaps and bounds(my role was computer engrg). Which is a good
thing. However also look at Excel whereby there are many sophisticated
features in that app, yet there are tools with Excel that permit you to lock
down a number of the features to permit uers the use of custom configured of
Excel pages. This permits simplifiec entries and reporting facilities..i.e.
Company Expense forms. Yet behind each cell often lies complex formulas that
operate on each entry of the cell, entered by the user. Many administrators
of Excel have developed slick company expense forms to such a degree that
when you open them, one would hardly recognize that they are actually using a
Excel spread sheet when they are filling in their expense after a company
trip. Yet in the background all the pre-configured operatives are being
employed to each cell entry that is being summitted by the employee. Hence,
if designed properly that user interface can walk the employee thru proper
use of company expenses and proper filing. So my next question to you is
where can I find some good info on use of Visual Basic to design Project user
interfaces? My point is there is still the role of the expert financial
accounts and wizzes to use Excel and thru the evolution of tools within or
companion to Excel, one can provide slick interfaces for those environments
whereby financial users of lesser degrees can use the power of Excel with
less involvement of the details or calculations of Excel. Hey back in the
day, everyone had to know how to drive a "Stick Shift"...and I a "Slide
Rule"...then came the "Hydro-Matic"...and so on...Contact me directly(as this
mightbe diverting from purpose of this posting)
(e-mail address removed) to take off-line for bit. Thanks
Much...SunBird II
 
S

SunBird II

Hey.. As soon as I sent my thoughts on this MS Project User Interface, I
scrolled over to "Office Discussion Group - Office Developer" and found this
conversations -

Subject: Creating project tasks through automation has bad performance
4/12/2006 2:53 AM PST

By: Mark de Waal

Seems like there may be others that might have simular interest. Looking for
your feedback. - Cheers - SunBird II
 
S

SunBird II

Is there some reference can use to see proper way to rollup several projects
onto
master project sheet? And keep summary rollup data?
 

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