Re: Completion should be effort invested instead of percentage of duration

[Kurt Maute <kurt maute us>]

On Sun, 2007-01-07 at 22:59 +0100, Maurice van der Pot wrote:

> Do you have any examples where it makes sense for the user to specify 
> %complete instead of work done? Because if there is no such situation, 
> then %complete should be no more than a different view on the same 
> information and not something that could be fixed to force a recalculation 
> of work done.

Actually, I think I need to backtrack on some of what I said before.  I
think we need to make a distinction here between how much of the task
has been completed and how much work (effort) has been logged against
it.  If 'work done' represents the amount of the task that's been
completed expressed as hours (or days as the case may be), then what I
said before holds true.

However, if 'work done' is the amount of time spent on the task so
far... say 8 hours of a 16 hour task, it doesn't mean that the task is
half complete.  After all, maybe we put a trainee on the task when we
originally thought we'd get the seasoned professional, or maybe we just
ran into some trouble and its only 25% complete.

Its important to make this distinction, since we'll eventually want to
create some reports that show Earned Value and other standard project
metrics.  http://en.wikipedia.org/wiki/Earned_value_management



> In any case, the %complete feature interacts with the 'fixed duration'
> feature, so in order to provide useful functionality for the former I
> first need to understand the latter.
> 
> What kinds of tasks would have a fixed duration?

They're often (but not always) tasks that involve factors that are out
of your control.  There are good examples from construction - such as
the application of materials that require time to cure:

Apply Polyurethane:  work: 1 hour  Fixed Duration: 1 day

In this case, you may need only 1 hour to lay down a coat of oil based
polyurethane on the wood floors, but it won't be ready for another coat
until the next day.  So if you want 3 coats, you'd do this:

1.0 Refinish Wood Floors (Summary Task)
  1.1 Sand Floors    work: 6 hours  duration: 6 hours
  1.2 Apply Polyurethane   work: 1 hour   fixed duration: 1 day
Predecessor:  1.1
  1.3 Apply Polyurethane   work: 1 hour   fixed duration: 1 day
Predecessor:  1.2
  1.4 Apply Polyurethane   work: 1 hour   fixed duration: 1 day
Predecessor:  1.3


> I noticed that the length of fixed duration tasks is calculated by
> essentially taking the starting time of the first working period and the
> finishing time of the last working period on each day and subtracting
> the difference from the total duration until it's 0.
> 
> This means that the length does depend in part on the working time,
> while it does not take all of it into account. How is this feature used?
> What kinds of activities go on during lunch time but not, for instance,
> after the working day ends?
> 
> I think it would make more sense if a fixed duration task with a
> duration of 7 days would either be as long as a fixed work task with 7
> days of work and no resources, or 2 days shorter (if it should continue
> through the weekend). But again, I don't know of any real-world examples
> yet.

I see what you mean.  There's a bug out there:
http://bugzilla.gnome.org/show_bug.cgi?id=389752

Maybe what we need is a 'include non-working time' check box to give the
user more control.  I can see it going either way.

-- 
Kurt Maute <kurt maute us>