Cost Estimation: Flashcards
Cost estimation is a blend of ___ and ____.
Art, Science
True or False: a high degree of accuracy is attainable without much effort
False
Factors that affect cost estimation?
Optimism
Marketing
Blaming/Killing the messenger
Scoping of requirements
Ways to get better cost estimates:
- Study lessons learned
- insist on estimation integrity
- Analyse cost early on
- Define project better
Cost Estimation Methods:
- Bottom up analysis
- Analogous Estimating
- Parametric Esimating
Estimation Method: Bottom up Analysis
estimate based on material/labor costs
not appropriate for conceptual design phase
Estimation Method: Analogous
Experience based approach (heuristic)
based on similar products
can be applied at any level
Not flexible during trade studies due to limited past cases
Estimation Method: Parametric
Based on CERs (Cost Estimation Formulas)
Can apply complexity factor for changing tech
Accounts for hardware dev
Cost Estimation methods with appropriate lifecycle phase:
Pre A & A - Parametric
B - Any method
C - Bottom up (detailed)
D - Bottom up (detailed)
True or False: Use of the detailed cost estimation method increase over project maturity.
True
True of False: Use of the parametric cost estimation method increases over project maturity.
False
Pros & Cons: Parametric Estimation
Pros:
- less time consuming
- more effective for what ifs
- More consistent estimates
- Traceable to past space systmes
Cons:
- applicable to set range of historical data
- Must adjust CERs for new technology an shit
- Usually not accurate for later phases in project
CER
Cost Estimate Formula:
We fit curves to data points between some measured parameter (weight/volume) and associated cost
We should ____ historical data to account for gradual inflation over time when using the parametric estimation method.
Normalize/Adjust/Account for
The ‘complexity factor’ for a CER ______ with the increase in component design changes.
Complexity