Question: A random sample of 85 graduate level classes was selected and the number of enrolled students during the Fall 2017 semester was recorded for each. The data is displayed in the boxplot below. Use this boxplot to describe the shape of the distribution of the number of enrolled students in this sample of 85 graduate level classes. (Boxplot Image)
Answer Choices:
A. Skewed Left
B. Skewed Right
Answer: B – Skewed Right
Question: True or false: with quantitative variables, to completely describe the relationship between the two variables it is recommended to construct a scatterplot to graphically display the relationship and compute the correlation coefficient to numerically describe the relationship.
Answer Choices:
A. True
B. False
Answer: A – True
Question: The regression line that gives the linear relationship between the number of academic student does each week is predicted number of paid hours =50.24 – 2.48(number of academic credits). Which of the following is the correct interpretation of the slope of this regression line?
Answer Choices:
A. If the number of paid hours of work increases by 1 hour, then the predicted number of academic credits decreases by 2.48 credits.
B. If the number of academic credits is 2.48, then the predicted number of paid hours of work is 50.24 hours.
C. If the number of academic credits increases by 1 credit, then the predicted number of paid hours of work decreases by 2.48 hours.
D. If the number of academic credits increases by 1 credit, then the predicted number of paid hours of work increases by 50.24 hours.
E. If the number of paid hours of work increases by 1 hour, then the predicted number of academic credits increases by 50.24 credits.
Answer: C – If the number of academic credits increases by 1 credit, then the predicted number of paid hours of work decreases by 2.48 hours.
Question: The regression line that gives the linear relationship between the number of academic credits a VCU student is taking this semester and the number of hours of paid work the student does each week is predicted number of paid hours =50.24 – 2.48(number of academic credits). Which of the following is the correct interpretation of the intercept of this regression line?
Answer Choices:
A. If the number of paid hours of work is 0 hours, then the predicted number of academic credits is 50.24 credits.
B. If the number of academic credits is 0 credits, then the predicted number of paid hours of work is 50.24 hours.
Answer: B – If the number of academic credits is 0 credits, then the predicted number of paid hours of work is 50.24 hours.
Question: True or false: a stem-and-leaf plot and a histogram are graphical methods for displaying qualitative data.
Answer Choices:
A. True
B. False
Answer: B – False
Question: Which of the following statistics is a measure of spread that would be resistant to outliers?
Answer Choices:
A. Mean
B. Median
C. Range
D. Interquartile Range
E. Standard deviation
Answer: D – Interquartile Range
Question: When describing a distribution, which of the following things must you describe?
Answer Choices:
A. Center, only
B. Center, size, shape and unusual features
C. Center and spread
D. Center, spread, shape and unusual features
Answer: D – Center, spread, shape and unusual features
Question: A random sample of 85 graduate level classes was selected and the number of enrolled students during the Fall 2017 semester was recorded for each. The data is displayed in the boxplot below. Use this boxplot to describe the shape of the distribution of the number of enrolled students in this sample of 85 graduate level classes. (Boxplot Image)
Answer Choices:
A. Skewed Left
B. Skewed Right
Answer: B – Skewed Right
Question: True or false: with quantitative variables, to completely describe the relationship between the two variables it is recommended to construct a scatterplot to graphically display the relationship and compute the correlation coefficient to numerically describe the relationship.
Answer Choices:
A. True
B. False
Answer: A – True
Question: The regression line that gives the linear relationship between the number of academic student does each week is predicted number of paid hours =50.24 – 2.48(number of academic credits). Which of the following is the correct interpretation of the slope of this regression line?
Answer Choices:
A. If the number of paid hours of work increases by 1 hour, then the predicted number of academic credits decreases by 2.48 credits.
B. If the number of academic credits is 2.48, then the predicted number of paid hours of work is 50.24 hours.
C. If the number of academic credits increases by 1 credit, then the predicted number of paid hours of work decreases by 2.48 hours.
D. If the number of academic credits increases by 1 credit, then the predicted number of paid hours of work increases by 50.24 hours.
E. If the number of paid hours of work increases by 1 hour, then the predicted number of academic credits increases by 50.24 credits.
Answer: C – If the number of academic credits increases by 1 credit, then the predicted number of paid hours of work decreases by 2.48 hours.
Question: The regression line that gives the linear relationship between the number of academic credits a VCU student is taking this semester and the number of hours of paid work the student does each week is predicted number of paid hours =50.24 – 2.48(number of academic credits). Which of the following is the correct interpretation of the intercept of this regression line?
Answer Choices:
A. If the number of paid hours of work is 0 hours, then the predicted number of academic credits is 50.24 credits.
B. If the number of academic credits is 0 credits, then the predicted number of paid hours of work is 50.24 hours.
Answer: B – If the number of academic credits is 0 credits, then the predicted number of paid hours of work is 50.24 hours.
Question: Suppose a test is conducted with a p-value = .0340 and α = .05. What decision do we make?
Answer Choices:
A. Fail to reject the null hypothesis
B. Reject the null hypothesis
Answer: B – Reject the null hypothesis
Question: Atlantis Paradise Island is an ocean-themed resort on Paradise Island in the Bahamas. Of interest is to determine the proportion of all visitors to the Bahamas in 2019 that spent some time at Atlantis Paradise Island. As reported by the department of tourism the total number of visitors in 2019 was 120,000. In this scenario, 120,000 is an example of parameter or statistic?
Answer Choices:
A. Parameter
B. Statistic
Answer: A – Parameter
Question: For each GRTC Pulse, the number of stops it makes per day are counted. What type of characteristic is number of stops for each GRTC Pulse?
Answer Choices:
A. Categorical variable
B. Continuous quantitative variable
C. Discrete quantitative variable
D. Constant
Answer: C – Discrete quantitative variable
Question: When describing the relationship between two variables, what things must you describe?
Answer Choices:
A. Center, shape, and unusual features
B. Direction and Form
C. Color and size
D. Direction, form, and strength
Answer: D – Direction, form, and strength
Question: A student computes the correlation coefficient to be r = +1.32. What does this value tell you?
Answer Choices:
A. There is a strong, positive linear relationship between the two variables
B. The student either doesn’t know what they are doing or made a calculation error (or both)
C. There is a strong, positive, nonlinear relationship between the two variables
Answer: B – The student either doesn’t know what they are doing or made a calculation error (or both)
Question: Of interest is to study the relationship between the number of academic credits a VCU student is taking this semester and the number of hours of paid work the student does each week. Specifically, of interest is to use the number of academic credits the student is taking to predict the number of hours of paid work the student does each week. Based on the information above, which of the following is the correct identification of the independent variable X and the dependent variable Y.
Answer Choices:
A. X = number of hours of paid work the student does each week Y = number of academic credits a VCU student is taking
B. X = number of academic credits a VCU student is taking Y = number of hours of paid work the student does each week
Answer: B – X = number of academic credits a VCU student is taking Y = number of hours of paid work the student does each week
Question: For a quantitative variable, when describing a distribution what things must you describe?
Answer Choices:
A. Direction, form and strength
B. Color and size
C. Center, spread, shape and unusual features
D. Center and spread
Answer: C – Center, spread, shape and unusual features
Question: What is the mean of a standard normal distribution?
Answer Choices:
A. 0
B. μ
C. x-bar
D. 1
Answer: A – 0
Question: What is the standard deviation of a standard normal distribution?
Answer Choices:
A. x-bar
B. μ
C. σ
D. 1
Answer: D – 1