Statistical Quality Control Practice Test 9

1. Which of these is a correct definition for an MSP?

Process in which data at a point in time consisting of measurement from single sources

Process in which data at a point in time consisting of measurement from several sources

Process in which many values of data come from single source

Process in which same value of data comes from several sources

2. EWMA and cusum charts can be used for the short production runs because ____________

They detect larger process shift

They don’t detect process shift

They have shorter ARL

They are good in phase II

3. LCL for EWMA chart for Poisson distribution is written as ____________

LCL=\(μ_0+A_L \sqrt{\frac{λμ_0}{2-λ}\big\{1-(1+λ)^{2i}\big\}}\)

LCL=\(μ_0-A_L \sqrt{\frac{λμ_0}{2-λ}\big\{1-(1+λ)^{2i}\big\}}\)

LCL=\(μ_0+A_L \sqrt{\frac{λμ_0}{2-λ}\big\{1-(1-λ)^{2i}\big\}}\)

LCL=\(μ_0-A_L \sqrt{\frac{λμ_0}{2-λ}\big\{1-(1-λ)^{2i}\big\}}\)

4. If the C_pk=0.9899, the usage of modified control charts is very necessary.

False

True

5. When the type I error is specified, which of these is correct expression for the UCL of the modified control charts?

\(UCL=USL+\left(Z_δ-\frac{Z_α}{\sqrt{n}}\right) \sigma \)

\(UCL=USL-\left(Z_δ-\frac{Z_α}{\sqrt{n}}\right) \sigma \)

\(UCL=USL-\left(Z_δ+\frac{Z_α}{\sqrt{n}}\right) \sigma \)

\(UCL=USL+\left(Z_δ+\frac{Z_α}{\sqrt{n}}\right) \sigma \)

6. When are the sources, or streams, in an MSP, considered to be identical?

When the process is out-of-control

When the process is in-control

The sources are never identical in any of the states of process

When the process is running

7. Which of these is a correct expression for the UCL of the modified control charts when the type I error is not specified?

\(UCL=USL+\left(Z_δ+\frac{3}{\sqrt{n}}\right) \sigma \)

\(UCL=USL+\left(Z_δ-\frac{3}{\sqrt{n}}\right) \sigma \)

\(UCL=USL-\left(Z_δ+\frac{3}{\sqrt{n}}\right) \sigma \)

\(UCL=USL-\left(Z_δ-\frac{3}{\sqrt{n}}\right) \sigma \)

8. What is used instead of Nominal values when the nominal value is not given in the case of DNOM approach?

Historical process average

Historical process variance

New standard deviation

Historical process standard deviation

9. If the process mean increases very much, the modified control charts are not appropriate.

True

False

10. It is impossible to get desired values of α, β, γ, and δ in the acceptance control charts.

True

False