What do poker, Greek oracles, an Italian mathematician from the Middle Ages, and the path of hurricanes have in common? Given the title of this presentation, chances are it has something to do with estimation, and you’ll have to attend this session to get the full connection. Kent McDonald explores the challenges and realities of trying to estimate software-related knowledge work—analysis, testing, development, and the entire project effort. A major challenge is that there are no guaranteed ways to arrive at perfectly accurate estimates, which not surprisingly is why they are called estimates. Kent introduces and gives you a chance to practice quick and practical estimating techniques that will work in different situations—guesstimating, break it down and add it up, and planning poker. Kent has found that these “lite” estimation techniques are almost always just as informative as the ones you just spent six weeks formulating.
5. Has this ever happened to you?
Ok, great. The Sales
How long will it
VP promised an I just found out
take to build the
estimate to the about it this
commission
CEO next Monday. morning, so I’ll need
system?
It better be right. to do some analysis .
21. Your turn…
Want to create an online application for Mortgage Insurance
How long to deliver the online
application for Mortgage
Insurance?
A ballpark answer is sufficient.
22.
23. Does it address our issues?
Initial Uncertainty Accuracy/Effort Tradeoff
False Precision Differing Skill Levels
27. Assign factor to each small bit
Tasks Time Factor # of Total Time
(hour/bit) bits (hours)
Interfaces
GUI - Simple 8
GUI - Medium 16
GUI - Hard 24
System Interface - Simple 12
System Interface - Complex 30
Total Interfaces
Processes
Simple Process 16
Medium Process 32
Complex Process 48
Total Processes
29. This is where time cards may be
useful…
Know ahead of time
what you want to track
Build up information
over time
Often requires
excruciating detail in
time collection.
30. Identify How Many Bits
Tasks Time Factor # of Total Time
(hour/bit) bits (hours)
Interfaces
GUI - Simple 8 3
GUI - Medium 16 2
GUI - Hard 24 1
System Interface - Simple 12 3
System Interface - Complex 30 2
Total Interfaces 11
Processes
Simple Process 16 5
Medium Process 32 4
Complex Process 48 3
Total Processes 12
31. Do the math to get an estimate
Tasks Time Factor # of Total Time
(hour/bit) bits (hours)
Interfaces
GUI - Simple 8 3 24
GUI - Medium 16 2 32
GUI - Hard 24 1 24
System Interface - Simple 12 3 36
System Interface - Complex 30 2 60
Total Interfaces 11 176
Processes
Simple Process 16 5 80
Medium Process 32 4 128
Complex Process 48 3 144
Total Processes 12 352
33. What about analysis & testing &…
Percentage of
development hours
Estimate tasks
separately
You mean we have to
estimate analysis &
testing?
34. Data Warehouse Example
Adding a new source to
data warehouse
Count of sources
Count of tables/source
Count of
elements/table
Considerations of
complexity
35. Data Warehouse Example
1. Gather all the info
2. Plug it into a
spreadsheet
3. Look at the resulting
(realistic but “too
high”) number
4. Revise…
36. Your turn…
Want to create an online application for Mortgage Insurance
How long to deliver the online
application for Mortgage
Insurance?
Identify how you would break
this down to estimate
43. Calibrated Estimates in Ranges
Manage Moderate Manage Build Manage
Tracks Content Deadlines Program Venue
1 – 2 Days 3 – 5 Days 1 – 2 Days 4 – 6 Days .5 – 1 Days
9.5 – 16 Days
@ $100/hour & 8 hours/day
$7,600 – $12,800
Note, Entire team calibrated and
involved in determining these estimates.
44. For More information
How to Measure Anything:
Finding the Value of
Intangibles in Business
by
Douglas W. Hubbard
HowToMeasureAnything.com
45. Where it Helps
Initial Uncertainty Accuracy/Effort Tradeoff
False Precision Differing Skill Levels
48. Discuss (briefly) the item to estimate
As an Event Organizer
I want to know how
audience members vote by
athlete by gender So That
I can determine if men
and women vote differently.
53. Discuss outliers
Well, we changed the voting
I wasn’t sure we knew how
machines to ask gender a
Andwhy did youthe two
So how about pick during
Yeah, what she said.
to tell an audience
sign in last iteration, so it
king?
aces?
member’s gender.
should be easy
60. An Alternative to Planning Poker
1 2 3 5 8
User Story User Story User Story User Story
User Story User Story User Story User Story
User Story User Story
User Story User Story
62. Calibrated
Guestimate
Phase Based
Estimates
Break it
down add
it up
Set
expectation
for revisions
63. Agile
Comparison
Calibrated
to past
Estimates
projects Extrapolate
from
Velocity
Set
expectation
for revisions
64. If you remember nothing else
Initial Don’t spend
uncertainty more effort
means you will than it’s
not be accurate. worth.
Don’t imply Incorporate
more precision multiple
than is perspectives.
possible.
What do poker, Greek oracles, an Italian mathematician from the middle ages, and the path of hurricanes have in common? Given the title of this presentation, chances are it has something to do with estimation, but you’ll have to come see it to get the full connection.In case that wasn’t sufficient enticement, Kent McDonald discusses the challenges and realities of estimating knowledge work, be it analysis, testing, software development, or the entire effort. One big challenge and reality is there are no guaranteed ways to arrive at perfectly accurate or precise estimates, which ironically is why they are called estimates. Not being one to whine about a problem without offering a solution, Kent introduces and gives you a chance to practice some practical techniques that your team can use to quickly determine estimates that are just as informative as the ones you just spent six weeks formulating.