Question

1. A sample of 15 observations has a standard deviation of 4. The sum of the squared deviations from the sample mean is: (Points: 2)
        A) 19
        B) 56
        C) 60
        D) 224


2. A sample of 13 monthly sales figures (in thousands of dollars) are: 10, 6, 5, 10, 9, 7, 10, 9, 6, 8, 9, 6, and 6. What is the value of the sample standard deviation. (Points: 2)
        A) 2.81
        B) 3.18
        C) 1.83
        D) 2.11


3. A sample of 13 monthly sales figures (in thousands of dollars) are: 10, 6, 5, 10, 9, 7, 10, 9, 6, 8, 9, 6, and 6. What is the coefficient of variation? (Points: 2)
        A) 11.25
        B) 35.28
        C) 10.45
        D) 23.56


4. Chebyshev’s Theorem states that the percentage of observations in a data set that should fall within five standard deviations of their mean is: (Points: 2)
        A) 90%
        B) at least 90%
        C) 96%
        D) at least 96%


5. If the coefficient of correlation r= 0 , then (Points: 2)
        A) the slope of the regression line is zero
        B) there is no linear relationship whatsoever between the dependent variable y and the independent variable x
        C) the coefficient of determination is zero
        D) All of the above are correct


6. The Greek letters µ and s are examples of population parameters. (Points: 2)
        True
        False


7. The convenience sample is an example of probability sampling where every person or element in the population may not have an equal chance for inclusion in the sample. (Points: 2)
        True
        False


8. When the respondents to a questionnaire have different characteristics from those who did not choose to participate in the survey, the survey will likely suffer from: __________. (Points: 2)
        A) Sampling Error
        B) Response Error
        C) Non-response Error
        D) None-sampling Error


9. Which of the following variables probably could be measured in an observational study of airline travelers? (Points: 2)
        A) The brand of coffee they drink at home.
        B) The occupation of the traveler.
        C) How many frequent traveler miles they have earned.
        D) The gender of the traveler.


10. In a(n) _______ sample, the population is divided into layers; then a simple random sample of members from each layer is selected. (Points: 2)
        A) Simple Random
        B) Stratified
        C) Systematic
        D) Conveniece