Question

1. Selection bias occurs more frequently in systematic samples than in simple random samples. True or False

2. The service facility is a combination of:

1. Arrival rates and service rates
2. Servers and customers
3. Queue length and queue discipline
4. Channels and phases

3. An office copy room has three (3) copiers. Copy job time is normally distributed with a mean of four (4) minutes and a standard deviation of 40 seconds. Employees follow a poisson arrival pattern into the copy room. What is the appropriate model for this situation?

1. M/M/3
2. M/D/3
3. M/D/4
4. M/G/3
5. M/G/4

4. Assignable variations in a process are also called natural variations. True or false

5. T F Sample sizes of 4 or 5 can be used when building x-bar and R-control charts. True or false

6. The control chart:

       a. focuses on the time dimension of a system.

       b. captures the natural variability in the system.

       c. can be used for categorical, discrete, or continuous variables.

       d. all of the above

Answer 1

1) FALSE, systematic sampling is still thought of as being random if the periodic interval is determined beforehand and the starting point is random.

2) The service facility is a combination of Channels and pases.

3) (d) M/G/3, here M- Markovian, G general distribution and since there are only 3 copiers therefore M/G/3.

4) False as Assignable variations in a process are called unnatural variations.

5) False, it must be greater than 10.

6) d. all of the above.