BPI-Control Chart&PCI

In control charts, we use the sample mean plus or minus several standard deviations as control limits.

• 1
• 2
• 3
• 4

In control charts, the boundary of 2 standard deviations (2σ) is commonly referred to as...?

• Control limits
• Modified control limits
• Specification limits
• Warning limits

What type of variation requires changes to the system and management perspective?

• Chance causes
• Assignable causes
• Special causes
• Sporadic problems

Which control chart is used to detect changes in the mean values between groups?

• R chart
• X-bar chart
• S chart
• All of the above

The purpose of SPC is...?

• Identifying 'system errors'
• Identifying 'localized errors'
• Identifying variation
• All of the above

Which of the following process capability indices is incorrect?

• Used to assess a process's ability to meet specifications
• We typically need to first check if the data conforms to the assumption of normal distribution
• Usually requires at least 30 data points
• All of the above are correct

Which of the following best expresses the usefulness of a correlation study in a process improvement project?

• Eliminating sources of variation
• Assessing the strength of the relationships between variables
• Managing sources of variation
• None of the above