Sampling and True Difficulty

Chapter 1
An Introduction to Business Statistics

True/False

1. A population is a set of existing units.
Answer: True Difficulty: Easy

2. If we examine some of the population measurements, we are conducting a census of the population.
Answer: False Difficulty: Medium

3. A random sample is selected so that on each selection from the population every unit remaining in the population has an equal chance of being chosen.
Answer: True Difficulty: Easy

4. A process is in statistical control if it does not exhibit any unusual variations.
Answer: True Difficulty: Easy

5. An example of a quantitative variable is the make of a car.
Answer: False Difficulty: Easy

6. An example of a qualitative variable is the mileage of a car.
Answer: False Difficulty: Easy

7. Statistical inference is the science of using a sample of measurements to make generalization about the important aspects of a population of measurements.
Answer: True Difficulty: Medium

8. If we sample without replacement, we do not place the unit chosen on a particular selection back into the population.
Answer: True Difficulty: Medium

9. By taking a systematic sample, in which we select every 100th shopper arriving at a specific store, we are approximating a random sample of shoppers.
Answer: True Difficulty: Medium

10. When beginning a study, we define our variable of interest called a response variable.
Answer: True Difficulty: Medium

11. True/False questions are a general type of survey questions.
Answer: False Difficulty: Medium

12. Errors of observation are a class of survey error.
Answer: True Difficulty: Medium

Multiple Choice

13. Statistical methods help to:
A) Demonstrate the need for improvement
B) Identify ways to make improvements
C) Assess whether or not improvement activities have been successful
D) Estimate the benefits of improvement
E) All of the above
Answer: E Difficulty: Easy (REF)

14. Ratio variable have the following characteristics:
A)