# Sampling and True Difficulty

Topics: Sampling, Sample, Random sample Pages: 10 (1701 words) Published: September 24, 2011
Chapter 1

True/False

1. A population is a set of existing units.

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.

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

14. Ratio variable have the following characteristics:
A) Meaningful order
B) an inherently defined zero value
C) Categorical in nature
D) Predictable

15. When we are choosing a random sample and we do not place chosen units back into the population, we are: A) Sampling with Replacement
B) Sampling without Replacement
C) Using a Systematic Sample
D) Using a Voluntary Response Sample

16. Which of the following is a quantitative variable?
A) The make of a TV
B) A person's gender
C) Mileage of a car
D) Whether a person is a college graduate
E) Whether a person has a charge account

17. Which of the following is a categorical variable?
A) Air Temperature
B) Bank Account Balance
C) Daily Sales in a Store
D) Whether a Person Has a Traffic Violation
E) Value of Company Stock

18. Measurements from a population are called
A) Statistics
B) Observations
C) Variables
D) Processes

19. In studying processes, we are interested in examining a characteristic that tells us about the _____ of output. A) Random Sampling
B) Statistics
C) Variable
D) Quality

20. The two types of quantitative variables are:
A) Ordinal and ratio
B) Interval and ordinal
C) Nominative and ordinal
D) Interval and ratio
E) Nominative and interval

21. Temperature (in degrees Fahrenheit) is an example of a(n) ________ variable. A) Nominative
B) Ordinal
C) Interval
D) Ratio

22. Jersey numbers of soccer players is an example of a(n) ___________ variable. A) Nominative
B) Ordinal
C) Interval
D) Ratio

23. Weights of items obtained using a well-adjusted scale represents a(n) _____________ level of measurement. A) Nominative
B)...