LSS Week 6 + 7

Question 1

Why must you take a structured approach to root cause analysis?

Answer 1

To find the true cause of the problem and implement a permanent fix

Question 2

How can the Pareto diagram help you narrow the list of potential root causes?

Answer 2

It tells you which things occur most frequently

Question 3

The null hypothesis is:

Answer 3

What we expect to happen due to chance alone

Question 4

when would we use a paired t-test?

Answer 4

To test for significant changes in a sample before and after a process or time frame. Ex: Patient’s blood pressure before and after a 3-month training program.

Question 5

Why is the improve phase so important to the process?

Answer 5

It leads you to the best solution

Question 6

What is a Risk Priority Number (RPN)?

Answer 6

Severity, occurrence, and detection factored together

Question 7

Which method of designed experiment allows for the study of all main effects and interactions?

Answer 7

Full Factorial

Question 8

What does 5S stand for?

Answer 8

Sort, set in order, shine, standardize, sustain

Question 9

When should you pilot your solutions?

Answer 9

Cost, Difficulty of reversal, and consequences.

Question 10

The null hypothesis is

Answer 10

What we expect to happen due to chance alone

Question 11

What varies more; averages or individuals?

Answer 11

Individuals

Question 12

When should you pilot your solutions?

Answer 12

When failure costs are high, reversal is difficult and there may be unintended consequences.

Question 13

What is the purpose of Lean?

Answer 13

Understanding and eliminating waste in a process

Question 14

What do you need to calculate Z-scores?

Answer 14

The mean of the population

Question 15

This method of designed experiment allows for the study of ALL main effects and interactions

Answer 15

Full factorial

Question 16

When investigating potential root causes, what might be useful if the list becomes overwhelming?

Answer 16

Group them into meaningful categories but keep the full list

Question 17

What are the elements of a good implementation plan?

Answer 17

People, budget, change management, time line, and measures for success

Question 18

Why must you take a structured approach to root cause analysis?

Answer 18

To find the true cause of the problem and implement a permanent fix

Question 19

What question does FMEA answer?

Answer 19

What might cause a problem?
What is the risk assessment?
What are the next steps?

Question 20

What is a type I error?

Answer 20

When we reject the null, when in fact the null was true

Question 21

During the critical root causes tollgate, what do you need to prove to the sponsor?

Answer 21

Eliminating the critical root causes will close gaps in performance

Question 22

How can an affinity diagram help narrow a list of potential root causes?

Answer 22

It can identify differently named things that are actually the same or very similar

Question 23

Ensuring that a fixture is non-symmetric so that a part only fits into in the correct orientation is an example of what lean tool?

Answer 23

Poka Yoke

Question 24

How can the Pareto diagram help you narrow the list of potential root causes?

Answer 24

It tells you which things occur most frequently

Question 25

When using a control chart, one should gather data

Answer 25

In the order of production

Question 26

You want to find out if the average call length at a call center has decreased after implementing process improvements. What is the alternative hypothesis?

Answer 26

The average call time after the changes is less than the average call time before the changes

Question 27

What is the key difference between prevention and mitigation?

Answer 27

Prevention involves error-proofing and understanding process capabilities, while mitigation aims to reduce issue severity but may not eliminate it entirely.

Question 28

What tool would you use to determine whether the source of variation is due to within-piece, piece-to-piece, or time-to-time?

Answer 28

Multi-vari chart

Question 29

Why should you conduct your trials randomly?

Answer 29

Minimizes changeovers, Less expensive to run & Minimizes confounding of variables with noise

Question 30

The F-statistic is a ratio of what?

Answer 30

Variances