View
219
Download
3
Category
Preview:
Citation preview
STATISTICAL FORECASTING
DON’T DO IT
T. DEMARCO, T. LISTER: WALTZING WITH BEARS
ACCURACY OF ESTIMATION
SOURCE: TSAI, KLAYMAN, HASTIE: EFFECTS OF AMOUNT OF INFORMATION ON JUDGMENT ACCURACY AND CONFIDENCE
ESTIMATION BIAS
LEA
WORK TIME
LEAD TIME FLOW EFFICIENCY =
LEAD TIME
WORK TIME
LEA WAIT TIME
LEA
LEA
THROUGHPUT VS STORY POINTS
UNIVERSE’S PLANS
source: DOGHOUSEDIARIES
BASED ON THE WORK OF TROY MAGENNIS, LARRY MACCHERONE AND DOUGLAS HUBBARD
0
10
20
30
40
50
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
MONTE CARLO EXAMPLE
0
10
20
30
40
50
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
AVERAGE PACE FORECAST - SIMPLE REGRESSION
0
10
20
30
40
50
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
MONTE CARLO EXAMPLE: THROUGHPUT SAMPLES
2
2
5
8
4
0
10
20
30
40
50
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
MONTE CARLO EXAMPLE: THROUPUT DISTRIBUTION
2
2
5
8
4
0
10
20
30
40
50
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
MONTE CARLO EXAMPLE: UNLUCKY BRIAN
0
10
20
30
40
50
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
MONTE CARLO EXAMPLE: WORST CASE SCENARIO
0
10
20
30
40
50
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
MONTE CARLO EXAMPLE: BEST CASE SCENARIO
0
10
20
30
40
50
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
MONTE CARLO EXAMPLE
MONTE CARLO EXAMPLE
0
10
20
30
40
50
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
MONTE CARLO EXAMPLE
0
10
20
30
40
50
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
MONTE CARLO EXAMPLE
0
10
20
30
40
50
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
0
10
20
30
40
50
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
MONTE CARLO EXAMPLE
HISTORICAL DATA: COMPLETED STORIES
HISTORICAL DATA: TIMELINE
STATISTICAL MODEL: INPUT #1
WHY LEAD TIMES?
LEAD TIME
HISTORICAL DATA: LEAD TIMES
LEAD TIME DISTRIBUTION
LEAD TIME DISTRIBUTION
STATISTICAL MODEL: INPUT #2
HISTORICAL DATA: WORK IN PROGRESS
WORK IN PROGRESS DISTRIBUTION
READY…
0
10
20
30
40
50
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Iteration
SAMPLING LEAD TIME VALUES
SAMPLING LEAD TIME VALUES
SUM(LEAD TIME VALUES) = UNITS OF WORK
3
5
5
4
3
1
3
4
3
2
2
6
1
3
5
5
3
3
3
3
5
5
5
5
87
SAMPLING WORK IN PROGRESS
6 6 6 6 6 6 6 6 6 6
6 6 6 6 6 6 6 6 6 6
6 6 6 6 6 6 6 6 6 6
6 6 6 6 6 6 6 6 6 6
6 6 6 6 6 6 6 6 6 6
6 6 6 6 6 6 6 6 6 6
6 6 6 6 6 6 6 6 6 6
6 6 6 6 6 6 6 6 6
6 6
6
6 6 6 6 6
87
SAMPLING WORK IN PROGRESS
6 6 6 6 6 6 6 6 6 6
6 6 6 6 6 6 6 6 6 6
6 6 6 6 6 6 6 6 6 6
6 6 6 6 6 6 6 6 6 6
6 6 6 6 6 6 6 6 6 6
6
6
6
6 6 6
6
6
6
6
6
6
6
6
6
6
6
6 6
6
6
6
6 6
6
6
6
6
6
6
6
6 6
6
6
6
6
87
6
6
6 6
6
6
6
6
6
6
6
6
6
6
6 6
6
6
6
6 6
6
6
6
6
6
6
6
6 6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6 6 6 6
6
6 6
6
6
6
6 6 6 6
6
6
6
6
6
6
6 6 6 6
6
6
6
6 6 6
6
6 6 6
6
6
6
90% CONFIDENCE INTERVAL?
UNCERTAINTY
BE BETTER
SOURCES & RESOURCES
▸
▸
▸
▸
▸
▸
▸
▸
▸
▸
▸
▸
▸
Recommended