A principle of statistical thinking is that variation exists in all processes
A. True
B. False
Question 2 of 31
The purpose of Deming's Red Bead Experiment is to demonstrate how to perform an inspection.
A. True
B. False
Question 3 of 31
Deming's Funnel Experiment illustrates that people can and do create unwanted process variation by indiscriminately trying to remove common-cause variation.
Question 4 of 31
Special cause variation generally accounts for 80 to 95 percent of the observed variation in a production process.
Question 5 of 31
A way to reduce assignable-cause variation is to redesign the system.
A. True
B. False
Question 6 of 31
Tampering with a stable system can increase the variation in the system.
A. True
B. False
Question 7 of 31
Special-cause variation tends to be easily detectable using statistical methods.
A. True
B. False
Question 8 of 31
A lesson offered by the Red Bead Experiment is that setting numerical output goals for a process are meaningful because workers control the process.
A. True
B. False
Question 9 of 31
A system comprised of only common cause variation is unstable.
A. True
B. False
Question 10 of 31
A purpose of the Funnel Experiment is to demonstrate the effect of 'tampering.'
A. True
B. False
Question 11 of 31
Sample statistics are used to estimate population parameters.
A. True
B. False
Question 12 of 31
An airline that computes the average number of baggage handling errors that has occurred per 1,000 passengers in the last year is utilizing statistical inference.
A. True
B. False
Question 13 of 31
A discrete random variable can take on only finite values.
A. True
B. False
Question 14 of 31
A sample is a complete set or collection of objects of interest.
A. True
B. False
Question 15 of 31
Sample statistics are often used as point estimators for population parameters.
A. True
B. False
Question 16 of 31
Bias is a form of non-systematic sampling error.
A. True
B. False
Question 17 of 31
Separating a hospital into wards and then randomly selecting a sample of patients from each ward is an example of stratified random sampling.
A. True
B. False
Question 18 of 31
Products are boxed in groups of 25. Drawing a sample of boxes and inspecting all units in the boxes selected is an example of systematic sampling.
A. True
B. False
Question 19 of 31
As the sample size increases the standard error of the mean increases, all else being held constant.
A. True
B. False
Question 20 of 31
Sampling techniques are designed for manufacturing operations and not for service operations.
A. True
B. False
Question 21 of 31
Statistical thinking is a philosophy of learning and action based on all of the following principles except
A. All work occurs in a system of interconnected processes.
B. Variation exists in all processes.
C. All variation can be traced to human error.
D. Understanding and reducing variation are keys to success.
Question 22 of 31
All of the following are illustrated by the Red Bead Experiment except
A. Management is responsible for the system.
B. All the variation in the production of red beads came entirely from the process itself.
C Special cause variation can be predicted.
D. Numerical goals are often meaningless.
Question 23 of 31
A system governed only by common cause variation is a system that
A. insures high productivity.
B. is stable.
C. meets a customer's quality specifications.
D. has zero natural variation.
Question 24 of 31
Acting on every result as if it were a special cause of variation is known as
A. stabilizing.
B. bullwhipping.
C. tampering.
D. monitoring.
Question 25 of 31
_____ is the process of drawing conclusions about unknown characteristics of a population from data.
A. Logical inference
B. Post-data inference
C. Statistical inference
D. Random inference
Question 26 of 31
Characteristics of the population are called
A. point estimates.
B. random variables.
C. statistics.
D. parameters.
Question 27 of 31
The component of statistical methodology that includes the collection, organization, and summarization of data is called
A. descriptive statistics.
B. analytical statistics.
C. inferential statistics.
D. predictive statistics.
Question 28 of 31
The sampling method where every item in the population has an equal probability of being selected is called
A. simple random sampling.
B. stratified sampling.
C. systematic sampling.
D. judgment sampling.
Question 29 of 31
Which of the following constitutes an approach to reducing sampling error?
A. cross-checking research designs with knowledgeable analysts
B. questioning the assumption that tomorrow's and today's population are comparable
C. taking a larger sample from the population
D. reduce conditions that contribute to dissimilar population segments
Question 30 of 31
A ______ is a subset of items taken from a population.
A. point estimate
B. sample
C. variable
D. standard deviation
Question 31 of 31
Everything else being remaining constant, when the sample size _______, sampling error decreases.
A. increases
B. decreases
C. stays constant
D. none of the above