Week 3: Six Sigma Measure Phase Practice Questions

Welcome back to the 6 week Six Sigma Green Belt review.

Earlier this week we covered the Measure Phase of DMAIC. We stepped through dozens of concepts in each. You can see that here.

We also reviewed what some of the most popular certifying organizations like ASQ, IASSC, and Villanova require you know about these topics.

Today we’re going to review some of the kinds of questions you may be asked on your exam around those topics.

Ready? Let’s dive in!

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ASQ Six Sigma Measure Phase Questions

Question: A measurement system analysis is designed to assess the statistical properties of:

(A) gage variation
(B) process performance
(C) process stability
(D) engineering tolerances

Answer: (A) Gage variation. A measurement system analysis is designed to assess the statistical properties of gage variation. Process performance and stability can be determined in other ways. Engineering tolerances are calculated by need.

Question: For a normal distribution, two standard deviations on each side of the mean would include what percentage of the total population?

Answer: A half sigma is 19.1%, 1 sigma is 19.1+ 15, and 2 sigmas are 19.1% + 15% + 9.2% + 4.4 %  = 47.7%

Now double it to account for the other side of the median: 47.7% * 2 = 95.4%.

So, a process that follows the normal distribution inside can expect to have 95.4% of its values fall within 2 sigmas of the mean.

Question: When calculating the Cp index, what does the standard deviation represent in the formula Cp = (USL – LSL) / 6σ?

(A) The tolerance interval
(B) The confidence interval for the result
(C) The range of the process
(D) The variance of the index

Answer: (C) The range of the process is represented by 6 sigmas, or standard deviations in the Cp Index equation. Remember, 6 standard deviations account for nearly all eventualities (assuming normal distribution) of the process. 6 sigmas is a good approximation of the range of outcomes.

The USL – LSL (the upper and lower limits) could be representative of the tolerance interval. I’m not familiar with anything called the tolerance interval but the upper and lower limits are set by what is considered acceptable by the client. And those fit.

A confidence interval is a statistical measure used in hypothesis testing and is not pertinent to this question.

Variance is a specific term in Six Sigma. You can calculate variance by squaring the standard deviation, a term that does not appear in the Cp equation so we can eliminate this answer.

IASSC Six Sigma Measure Phase Questions

Question: As we calibrate our Measurement System to assure accurate data we frequently encounter Bias which is the ______ of a measured value from the ____ value.

(A) Spread, Mean of the population
(B) Deviation, hoped for
(C) Deviation, true
(D) Spread, idea

Answer: (c) Deviation, true. This is a definition question. See MSA.

Question: This formula Z = (X – µ)/σ is used to calculate a Z score that, with the appropriate table, can tell a Belt what ________________________.

Answer

A) Ratio the area under the curve is to the total population

B) Number of Standard Deviations are between X and μ

C) The Median of the sample population is

D) Proportion of the data is between X and μ

Answer: Proportion of the data is between X and μ. This is a definition question. See Z Scores.

Question: When a Belt is developing a Macro Process Map to define a complex process he will frequently include activities across various department to capture all the appropriate activity. He will use _____________ to show which department is responsible for which steps in the process. 

A: Subscripts

B: Superscripts

C: Swim Lanes

D: Fence Posts

Answer: This is by definition. See Process Mapping and Process Map Symbols.

Your Assignment

Assignment for everyone

A reminder that if you want to take these questions yourself you can via my online system. If you haven’t take then baseline exam yet, do so. You can find one available in all of my courses both paid and free.

As great as the baseline practice exams aren’t enough. You need to find more questions. 

Your assignment this week is to find and practice more questions for these topics.

Assignment for PYSSGB Students

If you are a Pass Your Six Sigma Green Belt member, take all of the individual topic quizzes as well as the the cumulative exams for Module 5. Let me know what you think. (Want to become a member? Sign up here.)

What Do You Think?

I’d love to know what you think about the material you need to know in these sections. Please take a minute to share your thoughts below. I’ll use these responses to decide the best way to improve the site to help the most number of people.

Next Time

Next week we will dive into the Analyze Phase of DMAIC.

I’d love feedback on how you thought the second week went. What was good, what could be better?

Happy studying, Ted