A simple, fun Six Sigma case study to explain the application of the DMAIC approach for process improvement and defect reduction.

1. a Six Sigma Case Study by XServe Consulting

2. Steve, Ronnie’s Manager, had earlier
warned him on several occasions for
coming late to office.
This time, it was the FINAL Warning!!!
RONNIE, You were late to work on 15
out of 26 Days in November. Treat this
as my Final reminder to you.
Steve
(The Angry Boss)
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contact@xserve.in
2

3. Ronnie met his girlfriend
Minnie for Dinner in the
evening.
Minnie assured an upset
Ronnie that she will help
him fix the problem.
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3

4. Problem Statement
In November 2013, Ronnie has been late to work on 15 out of 26
working days.
Ronnie in Nov-2013
Reporting Time
10:30 AM
Working Days
26
Defects (Late)*
15
Mean
10:35 AM
Standard Deviation
00:12
DPMO
576,923
Z st
1.31
*Defect: Days when Ronnie reported to work after 10:30 AM
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4

5. Let’s first look at the reasons for DELAY
The Start Time: Delay at Home
Early morning calls with Minnie
Breakfast
Waiting time for the
Catching up with Morning News
Elevator
Deciding what
Why do
Wake up time
to wear to work
Day of the
Week
Other Causes
Train
Don’t feel like
going to work
Mode of
Transport
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Car
you get
LATE to
work?
Route Taken
Average speed
Re-filling fuel in
the morning
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5

6. Reasons for Delay
Root Cause
Ronnie’s Vote
Minnie’s Vote
Final Verdict
Wake-up time
Almost the same
everyday
I agree. Your Good
Morning messages
seem to be
automated
No further analysis
Catching up with
Morning News
Again, no change in
schedule regardless
of me reaching on
time or late
What’s in News
anyways?
No further analysis
Breakfast
Almost the same
everyday
It’s high time you
watch your eating
habits
No further analysis
What to wear to
office
Hardly matters
I agree. Your
wardrobe is another
project in itself
No further analysis
Waiting time for the
elevator
Not much variation
I agree
No further analysis
www.xserve.in
contact@xserve.in
6

7. Reasons for Delay
Root Cause
Early morning calls
with Minnie
Ronnie’s Vote
Minnie’s Vote
I guess we need to
look at time spent
on calls everyday
Yes, if anything, the
time has to increase.
And it’s my call
No further analysis
everyday that wakes
you up
Mode of Transport – Have not used for
Train
months
Car – Route Taken
Average Speed
Yes
Final Verdict
No further analysis
There are three
routes although I
use two (A and B)
The distance and
traffic on each route Further analysis
can impact your
needed
travel time
Could be a reason
I always tell you to
be more careful
while driving
www.xserve.in
contact@xserve.in
Further analysis
needed
7

8. Reasons for Delay
Root Cause
Ronnie’s Vote
Minnie’s Vote
Re-filling of fuel in
the morning
I always re-fill while
coming back from
work
Yes, while you are
on your way to meet
me. Hence, the
No further analysis
delays. This one was
simple
Day of the week
Could be a factor as
traffic density is
higher on certain
days
I agree.
Further analysis
needed
Don’t feel like going
to work
This is never the
case. Zero
absenteeism in 3
months
That is because I
asked you to save
your leaves for our
annual holiday
No further analysis
www.xserve.in
contact@xserve.in
Final Verdict
8

9. Impact of Day of the Week on Ronnie’s Reporting Time
Boxplot of Reporting Time
 Test used: Analysis of
Variance (ANOVA)
 P-Value: 0.748
 R-Square: 11.77%
 Observation: There is no
significant difference in
Ronnie’s reporting time to
work on different days of the
week
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contact@xserve.in
9

10.  Minnie wanted to check the impact of selected route and
average driving speed
 As Ronnie did not have previous records of route and speed
(although he preferred Route A as that was the shortest
route), they set up a designed set of experiments with the
following settings:
Factor
Route Taken
Starting Time
Average Speed
Level (-1)
A
09:50 AM
65 kph
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Level (+1)
B
10:00 AM
75 kph
10

11. Given below is the DOE matrix that they set up. This is a
23 DOE with one replicate.
Standard
Order
12
9
11
16
4
14
2
15
3
13
10
1
7
6
8
5
Run Order
Route
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
B
A
A
B
B
B
B
A
A
A
B
A
A
B
B
A
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Average Speed Starting Time
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75
65
75
75
75
65
65
75
75
65
65
65
75
65
75
65
09:50
09:50
09:50
10:00
09:50
10:00
09:50
10:00
09:50
10:00
09:50
09:50
10:00
10:00
10:00
10:00
11

12. Results of the Experiment
P = 0.000
P = 0.136
P = 0.200
Although Route B is a slightly longer route (13.6 km compared to 12.7 km for
Route A), the average travel time for Route B is less than 20 minutes. Average
Speed (65 or 75) and Starting Time (09:50 am or 10:00 am) do not have a
significant impact.
www.xserve.in
contact@xserve.in
12

13. Ronnie’s Improvement Plan
 Avoid using the shorter Route A
 Always use Route B while going to
work
 Ensure to leave from home
between 09:55 am and 10:00 am
 Minnie also warned him against
rash driving and asked him to
maintain an average driving speed
of 65 to 70 kph
 They decided to record data for the
next two weeks
www.xserve.in
contact@xserve.in
13

14. Ronnie’s Improvement
Measure
Improve
Reporting Time
10:30 AM
10:30 AM
Working Days
26
12
Defects (Late)*
15
1
Mean
10:35 AM
10:17 AM
Standard
Deviation
00:12
00:07
DPMO
576,923
83,333
Z st
1.31
2.88
 Improvement: From a DPMO of 576,923 to 83,333
 Average reporting time: 10:17 am with just 1 defect out of 12 days
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14

15. Minnie wanted 0 Defect
Reporting time: 10:36 AM
What went WRONG?
Ronnie stopped at the ATM on his way to work as he had to pay his credit card bill.
This could have been avoided if pre-planned. What else could go wrong? Ronnie
needed a control plan.
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15

16. Risk Assessment
What can go Wrong?
Delay in waking up as
slept late (late night
party, talking to Minnie,
watching movie etc.)
Daily errands (ATM,
paying bills, buying
cigarettes etc.)
Severity
Probability
Risk Score
(lower the
better)
(lower the
better)
(lower the
better)
7
9
3
4
Action Plan
21
2 step wake up alarm system to be
followed: Alarm call @ 08:00 am
and call from Minnie @ 08:15 am
36
Bill pay schedule to be planned at
the start of the month. Extra pack
of cigarettes to be stored in the car.
Emergency fund (Rs. 2000) to be
stored in the office bag.
Traffic Jams or slow
moving traffic
9
3
27
Check for traffic updates while
having breakfast on Android App
and change route or leave early if
necessary
Flat Tyre
9
1
9
Low probability but check everyday
after evening walk
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16

17. Ronnie’s Improvement
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17

18. Results
Nov-2013
Dec-2013
Reporting Time
10:30 AM
10:30 AM
Working Days
26
24
Defects (Late)*
15
1
Mean
10:35 AM
10:15 AM
Standard Deviation
00:12
00:06
DPMO
576,923
41,667
Z st
1.31
3.23
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Significant reduction in Defects
(DPMO reduced from 576,923 to
41,667)
&
A
Happy
Boss
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18

19. a Six Sigma Case Study by XServe Consulting

20. Questions
contact@xserve.in
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Twitter Handle: XServeIn
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20