Fixed duration given, but changes

[Milind]

Hello
A task takes 5 days, I assign two resources with fixed duration constraint,
still sometime the duration gets changed. I add more resources with same
parameters, still the duration gets reduced. Any hidden setting needs to be
looked into?
Milind

 

[Mike Glen]

Hi Milind ,

Welcome to this Microsoft Project newsgroup

You might like to have a look at my series on Microsoft Project in the
TechTrax ezine, particularly #10 - Multiple Resource Assignments, at this
site: http://tinyurl.com/2xbhc or this:
http://pubs.logicalexpressions.com/Pub0009/LPMFrame.asp?CMD=ArticleSearch&AUTH=23
(Perhaps you'd care to rate the article before leaving the site,
Thanks.)

FAQs, companion products and other useful Project information can be seen at
this web address: <http://www.mvps.org/project/>

Hope this helps - please let us know how you get on

Mike Glen
MS Project MVP

wrote:

 

[Steve House [Project MVP]]

Paradoxical as it sounds, "fixed duration" does not mean the duration can't
change. It means that in the identity W=D*U if you change Work, Units are
recalculated and if you change Units, Work is recalculated. Once you have
made the initial resource assignment, whether you've assign just one
resource or you assign several all at once, the behavior of the duration is
governed by effort driven / non-effort driven setting. With effort driven
task adding or removing bodiues causes the duration to change and the work
to pro-rated. Non-effort driven OTOH means the work is recalculated and the
duration is kept constant. And a factor that can modify that behavior is
inherent in the very definition of duration itself, which for tasks with
multiple resources says that the duration is the time between when the
earliest starting resource begins his share and when the last finishing
resource wraps up his part of the work. If I put Bill and Joe on a one-week
task scheduled for next week and Bill is going on vacation for the week, Joe
will work the first week and Bill will do his share the second - the
duration would have stayerd 5 days if Bill wasn't going on vacation but
since he is, the duration becomes 10 days even though the total work and
assignment units are exactly the same in both cases.

 

[Gérard Ducouret]

Hi Steve,
May be I misunderstood your statement:
<<With effort driven task, adding or removing bodies causes the duration to
change and the work to pro-rated. >>
I don't think so : With effort driven [Fixed Duration] task, adding or
removing bodies causes the Units to change.

Gérard Ducouret

 

[Steve House [Project MVP]]

You are correct - my brain fart as I use fixed duration extremely rarely.
In my view it is almost always used used inappropriately and only rarely is
an accurate description of reality. If I have Bob scheduled for 5 days to
paint a room and add Bill to help him, does that really mean they'll both
work at half their normal capacity so they can make the job still take 5
days with both of them on it? Not very likely! I think a lot of the time
people use fixed duration in an attempt to get the project schedule to look
like some preconceived notion they have of what the schedule is supposed to
look like, using task durations to represent the time alloted for a task
rather than the time required for the task.
--
Steve House [MVP]
MS Project Trainer & Consultant
Visit http://www.mvps.org/project/faqs.htm for the FAQs

Hi Steve,
May be I misunderstood your statement:
<<With effort driven task, adding or removing bodies causes the duration
to
change and the work to pro-rated. >>
I don't think so : With effort driven [Fixed Duration] task, adding or
removing bodies causes the Units to change.

Gérard Ducouret

Paradoxical as it sounds, "fixed duration" does not mean the duration can't
change. It means that in the identity W=D*U if you change Work, Units
are
recalculated and if you change Units, Work is recalculated. Once you
have
made the initial resource assignment, whether you've assign just one
resource or you assign several all at once, the behavior of the duration is
governed by effort driven / non-effort driven setting. With effort
driven
task adding or removing bodiues causes the duration to change and the
work
to pro-rated. Non-effort driven OTOH means the work is recalculated and the
duration is kept constant. And a factor that can modify that behavior is
inherent in the very definition of duration itself, which for tasks with
multiple resources says that the duration is the time between when the
earliest starting resource begins his share and when the last finishing
resource wraps up his part of the work. If I put Bill and Joe on a one-week
task scheduled for next week and Bill is going on vacation for the week, Joe
will work the first week and Bill will do his share the second - the
duration would have stayerd 5 days if Bill wasn't going on vacation but
since he is, the duration becomes 10 days even though the total work and
assignment units are exactly the same in both cases.

 

[Gérard Ducouret]

Steve,than the time required for the task.>>
That's effectively what I experimented too.

Gérard Ducouret

You are correct - my brain fart as I use fixed duration extremely rarely.
In my view it is almost always used used inappropriately and only rarely is
an accurate description of reality. If I have Bob scheduled for 5 days to
paint a room and add Bill to help him, does that really mean they'll both
work at half their normal capacity so they can make the job still take 5
days with both of them on it? Not very likely! I think a lot of the time
people use fixed duration in an attempt to get the project schedule to look
like some preconceived notion they have of what the schedule is supposed to
look like, using task durations to represent the time alloted for a task
rather than the time required for the task.
--
Steve House [MVP]
MS Project Trainer & Consultant
Visit http://www.mvps.org/project/faqs.htm for the FAQs

Hi Steve,
May be I misunderstood your statement:
<<With effort driven task, adding or removing bodies causes the duration
to
change and the work to pro-rated. >>
I don't think so : With effort driven [Fixed Duration] task, adding or
removing bodies causes the Units to change.

Gérard Ducouret

Paradoxical as it sounds, "fixed duration" does not mean the duration can't
change. It means that in the identity W=D*U if you change Work, Units
are
recalculated and if you change Units, Work is recalculated. Once you
have
made the initial resource assignment, whether you've assign just one
resource or you assign several all at once, the behavior of the

duration
is

governed by effort driven / non-effort driven setting. With effort
driven
task adding or removing bodiues causes the duration to change and the
work
to pro-rated. Non-effort driven OTOH means the work is recalculated

and
the

duration is kept constant. And a factor that can modify that behavior is
inherent in the very definition of duration itself, which for tasks with
multiple resources says that the duration is the time between when the
earliest starting resource begins his share and when the last finishing
resource wraps up his part of the work. If I put Bill and Joe on a one-week
task scheduled for next week and Bill is going on vacation for the

week,
Joe

will work the first week and Bill will do his share the second - the
duration would have stayerd 5 days if Bill wasn't going on vacation but
since he is, the duration becomes 10 days even though the total work and
assignment units are exactly the same in both cases.
--
Steve House [MVP]
MS Project Trainer & Consultant
Visit http://www.mvps.org/project/faqs.htm for the FAQs


Hello
A task takes 5 days, I assign two resources with fixed duration
constraint, still sometime the duration gets changed. I add more resources
with same parameters, still the duration gets reduced. Any hidden setting
needs to be looked into?
Milind