The Work field shows the total amount of time scheduled on a task for all assigned resources, the total amount of time to which a resource is scheduled on all assigned tasks, or the total amount of time scheduled for a resource on a task. The time-phased versions of these fields show values distributed over time.
The above definition of work is from MS Project, similar to the definition used by many other scheduling software. However, this is in conflict with the definition of time. If hours represent work and are not a measure of time how do account for time, how do you account for different resource productivity? How do you account for duration? Is it that duration and work are the same thing?
Work hours is another thing, it is not work, it does not represent work but effort duration, only represent assignment hours. Shall be called Hours, not Work. Some resources such as a 30-ton crane versus an 80-ton crane will produce different quantities of work for the same amount of assigned work hours. How can you differentiate between the actual works produced in one hour by each?
Using hours as the unit measure of work is misleading, is wrong, is absurd.Our learning and professional institutions shall be honest and warn about it; otherwise, the wrong use of the concept will continue spreading.
Regards,
Rafael
Hi Rafael
I use a single resource for duration modelling which I call hours.
This resource is extracted from the labour content in the cost plan so the time - cost - scope triangle is balanced.
Best regards
Mike Testro
BTW you are rapidly catching up on me - I must get some more threads in.
Hi to all and Many thanks to Mr.Rafael
I had a doubt of similar issue and got cleared by Mr.Rafel.I have even raised this issue to MS Project Expert Forum they came with the answer
""It doesn't :-(
In Project Work is measured based on time worked,not on physical quantities.
There is the possibility to enter a value called Physical Percent Complete (which can be used in earned value calculations) but if you want to use it you have to enter it yourself, Project does not calculate it.""
Regards
Shahul
Anoon,
F=ma = mass x acceleration
Acceleration = dv/dt = change of velocity over time
Velocity = dx/dt = change of location over time
Time is of utmost importance when you define work, but work per se is not time.
Of course the appropriate definition depends on the use of the concept. For accounting purposes work is measured in hours no matter if there is an output or not. For the Construction Industry as a whole, work is measured in physical units as Vladimir pointed out.
MS Project as well as P6, originally P3e are software developed by IT people, people who never accounted nor cared for how the construction industry defines work, perhaps followed the thinking of accountants who measure work by pay hour no matter what the employee produced. Primavera even issued a version of P3e called P3ec, P3 for people to relate it to P3 a product developed by other people, e to mean enterprise and c to mean construction, this marketing strategy was later abandoned.
In the Construction Industry we do not say an hour of effort by a 1cm backhoe yields the same work as an hour of effort a 2cm backhoe will yield. Still in our industry, time is of utmost importance with regard to work. We relate the time element to work with the concept of productivity.
Work = Physical Quantity = Sum of (Productivity x time)
Time = effort
Productivity = Physical Quantity/effort = Physical Quantity/ time
MS Project as well as P6 was never designed taking into account the language and the concepts used by many generations in the Construction Industry. They pretend the whole industry to adapt to their concept, but their concept is inappropriate for the purposes of a whole industry. Their problem is that in order to accommodate their software to the appropriate concept of work for the Construction Industry they would have to resort into major surgery in their software and even start from scratch.
Best regards,
Rafael
In construction we usually measure the work and the progress in physical units like 25m3 of 40m3 were already done.
Hi Rafael,
Work - they said Work = force multiplied by distance (W= F x D), so it doesn't involved time.
Let me ask you, what do you mean by Progress?
cheers
Evry measure for progress is a simulation.Planner should choose different measure for different situation.
For example, to the design or construction work, manhour is one of the most suitable measures ,but to the procurement maybe milestone.
And ,to the productivity, different contractor have different equipment and worker. the productivity gap is huge.
So,your plan and manhour assigned to the work should match the contractor and in accordance with your contract strategy. Overall, manhours can not solve all the problem ,but it is a good simulation to the progress measure.
(Sorry for the expresstion, i am just a half year english learner)
Rafael,
What should be correct method to measure progress if not hours?
Please explain.
Thanks
SE Ali