1. Which types of variablesare quantitative?
2. a.Continuous and discrete.
3. b.Ordinal and nominal.
4. c.Continuous and ordinal.
5. d.Nominal and discrete.

1 points

QUESTION 2

1. Which of the following is a nominal variable?
2. a.Whether someone has an iPhoneor a Samsungcellphone.
3. b.Satisfaction with an Internetprovider on a scale of 1 to 10.
4. c.Weight.
5. d.None of the above.

1 points

QUESTION 3

1. Which of the following graphs is appropriate for categoricaldata?
2. A.Histogram
3. B.Bar graph
4. C.Boxplot
5. D.All of the above

1 points

QUESTION 4

1. What is the difference between a histogram and a bar graph?
2. a.The bars of a histogram don't touch while the bars of a bar chart do.Histograms should be used for ordinal data, while bar graphs should be used for discrete data.
3. b.The bars of a histogram do touch, while the bars of a bar graph don't.Histograms are used fornumerical data, while bar graphs should be used for categorical data.
4. c.They are two different ways of saying the same thing.
5. d.The bars of a histogram do touch,while the bars of a bar graph don't.You can use both for any type of data -it's up to you to decide which one you would rather use.

1 points

QUESTION 5

1. Which of the following statements best describes what a mode is?
2. The most common observation.
3. The average of all observations.
4. The middle observation.
5. The range between the upper quartile and the lower quartile.

1 points

QUESTION 10

1. Which of the following measures of variation is robust to outliers?
2. A.the standard deviation
3. B.the variance
4. C.the interquartile range
5. D.the range

1 points

QUESTION 11

1. LQ, UQ, IQR and R are the lower quartile, upper quartile, interquartile range and range of a sample, respectively. An outlier is defined to be
2. A.less than LQ - 1.5LQ or greater than UQ + 1.5UQ
3. B.less than LQ-1.5IQR or greater than UQ+1.5IQR
4. C.less than LQ-2.5IQR or greater than UQ+2.5IQR
5. D.less than LQ-0.5R or greater than UQ+0.5R

1 points

QUESTION 12

1. Which of the following statements about the OLS residuals is TRUE?
2. A.Their sum is zero, and their sum of squares is smaller than that from any other line
3. B.their sum is zero, and their sum of squares is larger than that from any other line
4. C.their sum can be positive or negative, and their sum of squares is smaller than that from any other line
5. D.their sum can be positive or negative, and their sum of squares is larger than that from any other line

QUESTION 16

1. When using a regression line to calculate a prediction,which of the following is necessary?
2. A.The correlation between X and Y must be positive
3. B.The value of X must be within the range of the X valuesin the sample
4. C.The value of X must be one of the X valuesin the sample
5. D.All of the above

1 points

QUESTION 17

1. The coefficient of determination,R²,describes
2. A.The proportion of the variation of the residuals explained by X
3. B.The proportion of the variation in Y explained by the regression line
4. C.The correlation between Y and X
5. D.The proportion of the variation of Y not explained by X

QUESTION 19

1. For a non-seasonal time series, increasingthe number of observations included in a moving average:
2. A.makes the moving average more smooth
3. B.increases the end-effects
4. C.both A and B
5. D.neither A nor B