Question 1

Common and ______________ Cause Variation are the focus of Statistical Process Control.

Accepted Answer

Statistical Process Control focuses on Common Cause Variation, which is inherent in the process, and Special Cause Variation, which is due to specific, identifiable sources.

Question 2

Upon completion and validation of an improvement to a process a Belt and the Project Team create a Control Plan that contains which of these?

Accepted Answer

A Control Plan contains all of the items listed above: a standard description of the process change, a monitoring system to ensure continued compliance, and a summary of the critical metrics for process performance measurement. These components are essential to maintaining the improved process and ensuring that it continues to meet the desired outcomes.

Question 3

Relative to a Design of Experiments the term ________________ refers to variables being a linear combination of each other.

Accepted Answer

Collinear variables in a DOE mean they are perfectly correlated and can lead to multicollinearity issues.

Question 4

Following the completion of a LSS project the Belt not only creates a Control Plan he also develops a _____________ so those involved in the process know what to do when the critical metrics move out of spec.

Accepted Answer

A Response Plan outlines the steps to be taken when critical metrics move out of spec, including identifying the root cause of the problem and initiating corrective actions. A Call List may be included as part of the response plan. Chain-of-Command is not relevant to developing a response plan, and a Defect Analysis Plan is focused on analyzing defects, not responding to them.

Question 5

If in an experiment all possible variable pairs sum to zero the design is Orthogonal.

Accepted Answer

A design is orthogonal if the sum of products of all possible variable pairs is equal to zero.

Question 6

If an experiment has 5 factors and no replicates for a 2-level Experimental Design with 16 experimental runs which statement is incorrect?

Accepted Answer

The answer of If an experiment has 5 factors and...

Question 7

Which statement(s) are incorrect about Fractional Factorial Designs?

Accepted Answer

The answer of Which statement(s) are incorrect about Fractional Factorial...

Question 8

Which statement(s) are correct about the Factorial Plot shown here? (Note: There are 3 correct answers).

Accepted Answer

A) This can be observed from the upward trend of the lines connecting the low, medium, and high levels of cutting speed and the corresponding tool age values.
B) This can be observed from the fact that the line connecting the high level of metal hardness and the corresponding tool age value has a steeper slope than the line connecting the low level of metal hardness and the corresponding tool age value.
C) By looking at the coded coefficients for cutting speed and cutting angle in the equation for tool age, it can be observed that the coefficient for cutting speed is smaller in magnitude than the coefficient for cutting angle, indicating that cutting speed has a smaller effect on tool age compared to cutting angle.
D) This information cannot be determined from the plot alone.
E) These plots are not necessarily interaction plots, as they only show the main effects of each factor on the response variable.

Question 9

Range Charts are the technique used to determine if Special Causes are occurring within the subgroups of the ______________.

Accepted Answer

Range Charts are a type of SPC Chart that are used to determine if Special Causes are occurring within the subgroups. Histograms, NP Charts, and Pareto Charts do not involve tracking subgroup variation over time.

Question 10

Which statement(s) are correct about the Pareto Chart shown here for the DOE analysis? (Note: There are 2 correct answers).

Accepted Answer

The answer of Which statement(s) are correct about the Pareto...

Question 11

For her injection molding project a Belt needed to track the percentage of defectives of a particular sample set so she used a ___________ to display the data?

Accepted Answer

A P Chart is used for tracking the percentage of defectives in a sample set, which is exactly what Belt needs for her injection molding project. The other types of charts listed are used for different types of quality control data.

Question 12

Fractional Factorial, ____________and Response Surface Method are types of planned experiments.

Accepted Answer

Fractional factorial and factorial design are types of factorial design experiments. Response Surface Method is a type of optimization experiment. Multi-Vari Analysis and Baldridge Channels are not types of planned experiments but rather quality improvement methodologies. One Factor at a Time (OFAT) is a type of experimental design, but it is not as efficient or robust as factorial design or response surface methodology.

Question 13

Special Cause Variation falls into which two categories?

Accepted Answer

Special Cause Variation falls into two categories: Assignable and Pattern. Assignable causes are specific, identifiable reasons for variation, such as machine breakdowns or operator error. Pattern causes are recurring trends or patterns that can be observed in the data, such as seasonality or a shift in market demand. Option A is not correct as "Unnatural" is not a recognized term in statistical process control. Option B is not correct as Short Term & Long Term is a classification based on variation, whereas Special Cause Variation is a classification based on the source of variation. Option D is not correct as "Attribute" and "Discreet" are not relevant terms in statistical process control.

Question 14

Which of these graphs demonstrates conditions which would be sufficient to enable OCAP for the process?

Accepted Answer

The answer of Which of these graphs demonstrates conditions which...

Question 15

The Control Limits width varies if the sample size varies for which type of chart?

Accepted Answer

The answer of The Control Limits width varies if the...

Question 16

Which of these elements are not included in Implementation plans?

Accepted Answer

Cost/Benefit ratios are typically included in project proposals, but not necessarily in implementation plans. The other elements (work breakdown structure, risk management plans, planned audits of work completion) are commonly included in implementation plans.

Question 17

What conclusion is most correct about the Experimental Design shown here with the response in the far right column?

Accepted Answer

The answer of What conclusion is most correct about the...

Question 18

When a Belt Poka-Yoke's a defect out of the process entirely then she should track the activity with a robust SPC system on the characteristic of interest in the defect as an early warning system.

Accepted Answer

The answer of When a Belt Poka-Yoke's a defect out...

Question 19

Control Charts were developed by Dr. Shewhart to track data over time. To detect Special Cause variation the Control Charts use which of these?

Accepted Answer

Control Charts use Center Line and Control Limits to detect Special Cause variation. Data shift analysis and outlier analysis methods may be used in conjunction with Control Charts, but they are not the primary method of detecting Special Cause variation.

Question 20

If the production is for higher volume and monitoring and the Mean and variability is to be monitored for four machines producing product and the characteristic to be monitored is Variable Data, which SPC Chart is best to be selected?

Accepted Answer

The Xbar-R Chart is the best choice for monitoring mean and variability for four machines producing variable data at a higher volume. This chart is used for continuous data and is designed to track the central tendency of the process (mean) and the variability (range). The Xbar-R Chart is easy to use and interpret, making it an effective tool for process monitoring and control. The Individual-MR Chart is used for monitoring mean and variability for a single machine and is not suitable for multiple machines. The NP Chart is used for monitoring discrete data and is not suitable for variable data. The CUSUM Chart is used for detecting small shifts in the process mean and is not suitable for monitoring variability.

Exam 5: Certified Six Sigma Black Belt