I read, reviewed and digested the excellent The Art of Estimation by Steve McConnell and presented back what I'd learned about software estimation to the team.
2. A presentation I put together as
part of a digestion and book review
of the excellent Art Of Estimation
by Steve McConnell. Any mistakes
or inaccuracies are entirely my own
doing.
4. The client needs RiskForce IV before
next month or the Death Star will
implode.
How long do you think it will take?
P.s. We should softcode the
architecture in case we need to
integrate with their Other System
running on Paula Bean’s VM.
Love,
The Boss x
5. An estimate is an
unbiased, analytical
process to predict the
duration or cost of a
project.
16. Hi RiskWorks!
A good estimate
should be within
25% of actual results
75% of the time.
Steve McConnell
17.
18. For each question, fill in the upper and lower bounds that,
in your opinion, give you a 90% chance of including the
correct value.
Low High
estimate estimate
1. Surface temperature of sun
2. Latitude of Shanghai
3. Area of Asian continent
4. The year of Alexanda the Great’s birth
5. Total value of U.S currency in circulation in 2004
6. Total volume of the Great Lakes
7. Worldwide box office receipts for the movie Titanic
8. Total length of the coastline of the Pacific Ocean
9. Number of book titles published in the U.S. since 1776
10. Heaviest blue whale ever recorded
19. Answers
1. Surface temperature of sun 10,000°F /
6,000°C
2. Latitude of Shanghai 31 degrees North
3. Area of Asian continent 17,139,000 square miles
4. The year of Alexanda the Great’s birth 356 BC
5. Total value of U.S currency in circulation in 2004 $719.9 billion
6. Total volume of the Great Lakes 2.3 x 10^16 litres
7. Worldwide box office receipts for the movie Titanic $1.835 billion
8. Total length of the coastline of the Pacific Ocean 84,300 miles
9. Number of book titles published in the U.S. since 1776 22 million
10. Heaviest blue whale ever recorded 170 metric tons
49. We can easily identify early on
anything not worth pursuing
T-Shirt sizing chart
Feature Business value Development cost
Feature A Large Small
Feature B Small Large
Feature C Medium Large
Feature D Medium Medium
…
Feature Z Small Small
52. Use ranges not single points
with best case and worst case
estimates
Feature Best Case Worst Case
Feature A 1.25 2.0
Feature B 1.5 2.5
Feature C 2.0 3.0
Feature D 0.75 2.0
Feature E 0.5 1.25
Total 6.0 10.75
53. Use the PERT formula to get the effort
in the Expected Case
Expected case =
[Best Case + 4(MostLikelyCase) +
WorstCase] / 6
54. Always compare your estimates
to your actuals or you’ll never be
a better estimator