Estimating Flashcards
What is estimating funnel?
A representation of the increasing levels of estimating accuracy that can be achieved through the phases of the life cycle.
Early on, we dont have a clue so estimates are shit. As the project progresses, estimates are more accurate cos you know more.
What is parametric estimating?
Uses stats to form the estimate
Data on a spreadsheet used to provide parametric estimates for new schemes
What is comparitive (analogous) estimating?
Basing an estimate on similar things that have happened before.
Review similar projects and take this into account.
What is analytical estimating?
Work broken into work breakdown structure
Estimate each part and then add them up - simple
Needs to be sufficient details such that it contains enough detail for each work package to be estimated wiht accuracy
Only works for cost estimates
What is Delphi estimating?
Group of subject matter experts
Individually produce an estimate which they send to the facilitator who then plots them on a chart
Stops conferring and changing answers based on what others have said
What is good and bad about comparitive/analogous estimating?
Comparison with another project that is similar.
Good - current and based on experience, quick and cheap
Bad - assumptions when it could actually be different
Do this at the concept stage
What is good and bad about the parametric estimates?
Uses stats to do the estimate
Good - science behind it
Bad - skills to interpret data needed, only as good as the data
What is good and bad about analytic estimating?
Good - accurate
Bad - takes a long time, doesn’t fit iterative
What are the benefits and negatives of delphi estimate ?
Getting individual assessment from the doers and then having a range
Good - expert opinion
Bad - reliant on people and opinions with ulterior motives
Why do you re-estimate?
- new budget year
- budget has changed
- something new to the market that could be better
- over budget so far
- passage of time
- asked by sponsor
- Helps with decision gates
