How to Change resource allocation "Units" (on an existing assignment) so that it really works? RRS feed

  • Question

  • Hi,

    I am trying to setup/revise a schedule whereby my manager now wants to change few of the resources assigned on few existing tasks (having actuals and of "Fixed Units" type) to be allocated a 50% Unit (than the default 100%)

    When I changed the allocation under the "Resource" tab of Task Info pop-up window for the asked resource, I found that nothing is getting changed in schedule i.e. no change to mainly to "duration"? and nothing to cost, work values etc.

    Do I need to do some refresh or re-calculation such that changes appear whenever the allocation Units get changed? Should I re-assign the resource with new allocation units as this could refresh the values? What about the Task Type - should this be changed to Fixed duration from Fixed Units?

    Is something still getting changed behind the scene?

    What’s the best way of doing such changes in resource allocation units?. Should such changes ONLY be made at the start when there are no actuals done yet as I see a different behaviour?.

    Any help in handling this scenario/request would be appreciated. Thanks in advance for help.

    • Edited by Srini-coder Wednesday, November 7, 2012 4:24 AM re-phrase of text..
    Wednesday, November 7, 2012 3:05 AM

All replies

  • You do need to understand the importance of task type and take account of this in your management of changes to task resourcing. Always keep in mind the formula   Work=Units * Duration.   Where you have actuals against a task, the significant arguments in this formula would be remaining work, peak units and remaining duration.

    What this means for your team - decide what type each task is. Estimate the size of the project in those terms and then figure out what level of resourcing you can apply. In your initial question you said you wanted to change the units from 100% to 50%. You can do this either in the split screen view or in the resources tab of the task information box. When you do this, expect the duration (for a fixed work task) or the work (for a fixed duration task) to change.


    Wednesday, November 7, 2012 4:46 AM
  • Thanks. I know the place where to change the allocation units, however I guess, the main question is about deciding the correct Task Type for the scenario that I have mentioned above. From your reply, it seems that this is something I need to make a decision on myself. So, I guess there is not best practice out there to handle this.

    In that case, I think it would be good for me to change the current Task Type (from Fixed Units)  to "Fixed Duration" on those tasks, while I am reducing the allocation Units %, as this way the current project's overall duration could atleast remain at an expected period of around 1 yr than 2/3 yrs (for the case of Fixed Units).

    • Edited by Srini-coder Thursday, November 8, 2012 5:13 AM re-phrased the text...
    Wednesday, November 7, 2012 5:42 AM
  • Srini, understanding task types and how they affect the schedule calculation when changing tasks is really important. Opinions vary, but I advocate deciding what task type should be applied to each task right at the beginning - before estimating or assigning resources. You can think of the three task types this way:

    • Fixed work - building a wall - can be estimated in terms of the amount of heads down, solid effort required;
    • Fixed duration - boiling an egg - it's going to take 4 minutes of elapsed time however many people you put on the job;
    • Fixed units - help desk - someone is going to be staffing the desk whether there are many or few calls.

    It depends on your organisation but the purist's approach would be to say most tasks are fixed work - unless you know they are going to be fixed duration. Fixed units applies only to support activities and should not drive the schedule (or appear on the critical path). In your case, it looks as though the organisation is more comfortable with Fixed Duration scheduling. This is OK but expect the actual work done on an assignment to be skewed towards as late as possible by the resources.

    Project aslo includes the option for 'effort driven'. This is a hybrid of Fixed Duration or Fixed Units with Fixed Work applicable when you are changing the resources assigned to a task. Make sure you experiment with this to understand it before using it.

    Friday, November 9, 2012 3:09 PM