Project Management
Project ManagementTop Down/Bottom Up methods
Consensus methods
Snr/middle managers’ guess total project time & cost
Discussing/arguing to reach a decision on best guestimates
Firms seeking greater precision:
Delphi Method:
Group decision process of chance of certain events occurring
Exp. familiar with project use insight/exp. guessing project costs/times
Ratio methods
Macro methods use ratios to guess time & cost
E.g. contractors using no. of sq. ft. to guess cost/time to build a house
Apportion method
Common in standard projects but may differ/customise
Given good historical data, estimates made quick easy & accurately
Costs apportioned to phases/deliverables
Function point methods (software/system projects)
Est. based on “function points” (inputs, outputs, no. of data files)
E.g. estimating labor cost 1 person p/m could represent avr. 5 function points
Weightings used to find total no. function points
Learning curves
Projects needing same tasks, or product repeated several times
Repetition improves performance time
Time reduction of task performance can be predicted
Improvement pattern counted in “learning curve”
Reasons for Adjusting Estimates
Interaction costs hidden in est.
Normal conditions don’t apply
Things go wrong on projects
Changes in project scope & plans
Adjusting Estimates
Time/cost estimates of certain activities adjusted as risks
Clearer defined resources/situation details
Contingency Funds/Time Buffers
Made freely to offset doubt
Reduce likelihood of project cost/completion time
Added to overall project/specific activities/work packages
Determined from previous similar projects
Changing Baseline Schedule & Budget
Unforeseen events may mean reshuffling budget & schedule
Top Down | Bottom Up | Consensus Method | Function Point Method (software/systems) | Ratio Method | Learning Curves | Apportion Method |
Consensus methods
Snr/middle managers’ guess total project time & cost
Discussing/arguing to reach a decision on best guestimates
Firms seeking greater precision:
Delphi Method:
Group decision process of chance of certain events occurring
Exp. familiar with project use insight/exp. guessing project costs/times
Ratio methods
Macro methods use ratios to guess time & cost
E.g. contractors using no. of sq. ft. to guess cost/time to build a house
Apportion method
Common in standard projects but may differ/customise
Given good historical data, estimates made quick easy & accurately
Costs apportioned to phases/deliverables
Function point methods (software/system projects)
Est. based on “function points” (inputs, outputs, no. of data files)
E.g. estimating labor cost 1 person p/m could represent avr. 5 function points
Weightings used to find total no. function points
Learning curves
Projects needing same tasks, or product repeated several times
Repetition improves performance time
Time reduction of task performance can be predicted
Improvement pattern counted in “learning curve”
Reasons for Adjusting Estimates
Interaction costs hidden in est.
Normal conditions don’t apply
Things go wrong on projects
Changes in project scope & plans
Adjusting Estimates
Time/cost estimates of certain activities adjusted as risks
Clearer defined resources/situation details
Contingency Funds/Time Buffers
Made freely to offset doubt
Reduce likelihood of project cost/completion time
Added to overall project/specific activities/work packages
Determined from previous similar projects
Changing Baseline Schedule & Budget
Unforeseen events may mean reshuffling budget & schedule
Top Down | Bottom Up | Consensus Method | Function Point Method (software/systems) | Ratio Method | Learning Curves | Apportion Method |