1. Which of the following statements is true?
A. When taking a sample from the population, the variable involved will always be qualitative.
B. A population is the object upon which we collect data.
C. In a true census, no inferential statistics can be done, because the entire population is the sample.
D. The definition of a census is the decennial census of the United States of America.
2. In a sample with mean x = 12 and standard deviation s = 3.5, a data point at 16.8 would have what sample z-score?
D. We can’t know the answer without knowing the population mean μ and standard deviation σ.
3. Use the following data sample to answer the question. 4, 14, 6, 9, 21, 3, 7, 10
What is the variance of this data sample?
4. Use the following data sample to answer the question. 4, 14, 6, 9, 21, 3, 7, 10
What is the standard deviation of this data sample?
5. Consider the following chart:
Which of the measures of central tendency would best represent that data?
D. Standard deviation
6. To answer the question, refer to the following list of raw data.
63, 71, 72, 77, 77, 78, 86, 77, 88, 88
What is the mean for the data?
7. To answer the question, refer to the following list of raw data. 63, 71, 72, 77, 77, 78, 86, 77, 88, 88
What is the mode for the data?
8. To answer the question, refer to the following data.
Ten students were sampled at random from a student population. Each was asked how many courses he or she was planning on studying in the upcoming year. The following is a list of the reported data values: 1, 2,
2, 3, 4, 5, 5, 5, 5, 6
What is the variance for the data values?
9. A particular sample contains 50 data values. According to Chebyshev’s theorem, which of the following is the number of values you would expect to fall within 3.0 standard deviations of the mean?
10. When a sample is taken from a larger population, this suggests that which of the following will be used?
A. Descriptive statistics
B. Inferential statistics
C. Computation of a sample mean
D. Independent events
11. Which of the following are parameters of a population?
A. σ and n
B. μ and σ
C. α and σ
D. μ and x
12. A population is a collection of _______ about which we will measure certain characteristics or properties, called _______.
A. individuals, sample values
B. experimental units, variables
C. people, traits
D. data, numbers
13. Which of the following statements about interpreting standard deviation is true?
A. Neither Chebyshev’s Rule nor the Emprical Rule require any assumptions about the frequency distribution.
B. Neither the Empirical Rule nor Chebyshev’s Rule can be applied to data unless the frequency distribution is mound-shaped and symmetrical.
C. Chebyshev’s Rule can’t be applied unless the frequency distribution is mound-shaped and symmetric. The Empirical Rule can
be applied to any data set, regardless of the shape of its frequency distribution.
D. The Empirical Rule can’t be applied unless the frequency distribution is mound-shaped and symmetric. Chebyshev’s Rule can be applied to any data set, regardless of the shape of its frequency distribution.
14. Given the data set 3, 6, 2, 9, –1, 0, compute Σ(x + 1)2.
15. When creating a histogram, it’s important to ensure that the classes of data satisfy which properties?
A. They must be mutually exclusive and exhaustive.
B. They must include each interval on the number line.
C. No requirements are made; the individual creating the graph is free to choose any classes.
D. They must be all the same size.
16. Which of the following involves inferential statistics as opposed to descriptive statistics?
A. A class of 50 statistics students earned an average grade of 73.5.
B. A local cable system, using a sample of 500 subscribers, estimates that 40 percent of its subscribers watch a premium channel
at least once per day.
C. The city business office reported 35 building permits for new single-family housing units.
D. The Alcohol, Tobacco and Firearms department reported that Houston had 1,791 registered gun dealers in 1997.
17. Several ways to make a bar graph deceptive appear below. Which of these is sometimes used to exaggerate differences from one data value to the next?
A. Making the graph shorter than it needs to be
B. Making the graph taller than it needs to be
C. Starting the vertical axis at a point greater than zero
D. A gap in the vertical axis
18. If a great many data values cluster to the left of a data distribution, which then tails off to the right, the distribution is referred to as
A. leftward skewed.
B. rightward skewed.
19. What is the difference between a histogram and a bar chart?
A. A histogram and a bar chart both reflect qualitative data.
B. The adjacent rectangles in a bar chart have a gap, while those for a histogram don’t.
C. The adjacent rectangles in a histogram have a gap, while those for a bar chart don’t.
D. A histogram reflects qualitative data, while the bar chart represents quantitative data.
20. Which of the following statements is true about a stem-and-leaf plot?
A. It separates data at the decimal point, creating horizontal rows whose values are close together.
B. Stem-and-leaf plots are histograms whose bars have been arranged in decreasing order of frequency.
C. It involves creating columns of dots, one for each datum in the sample.
D. It uses vertical bars to illustrate a probability distribution.