Chapter 4

For the following ordered set of data, find the 60th percentile. 0, 2, 3, 5, 5, 6, 8, 10, 10, 11, 12, 14, 16

10

For the following ordered set of data, find the 90th percentile. 0, 2, 3, 5, 5, 6, 8, 10, 10, 11, 12, 14, 16, 20, 23

21.2

For a given data set, suppose Q1 = 70, Q2 = 80, Q3 = 100. Which of the following is true about outliers?

An observation of 20 would be an outlier.

When you create a dot plot, you do which of these operations? Select all that apply.

"Pile up" dots that are too close to show separately. Place a dot along a horizontal scale for each observation.

Match the quartiles on the left with their definition on the right.

First Quartile matches Choice Separates the bottom 25% of the data from the upper 75% Second Quartile matches Choice Separates the bottom 50% of the data from the upper 50% Third Quartile matches Choice Separates the bottom 75% of the data from the upper 25%

If a set of data exhibits significant positive skewness, then which of the following would be expected of Pearson's coefficient of skewness?

The coefficient should be close to 3.

Which one of these statements is not part of the description of a scatter diagram?

The data points are connected to create a graph.

Which one of the following pairs of variables would be best-suited for a contingency table?

Favorite color or Gender

What is the function of "quartiles"?

To divide a set of observations into four equal parts

What would the location of the 11th percentile be for a data set with 50 observations?

5.61

What would the location of the 83rd percentile be for a data set with 40 observations?

34.03 (40+1)(83/100)=34.03

Suppose a given data set has the following characteristics: Minimum value: 120 Q1: 160 Q2: 190 Q3: 200 Maximum Value: 220 Which of the following is true about the distribution of the data?

Distribution is negatively skewed

Contingency tables are used for summarizing data of what level? Select all that apply.

Ordinal and Nominal

The interquartile range is a measure of dispersion usually used along with the median. What is the definition of interquartile range?

The distance between the first and third quartile.

Dot plots allow one to observe which of the following? Select all that apply.

The spread in a distribution. The shape of a distribution. The center of a distribution.

Which of the following is not a measure of position?

Standard Deviation

Which of the following are features of a dot plot? Select all that apply.

One dot for each observation. Dots "piled up" for observations very close together. A horizontal line indicating the possible values of the data.

Which of the following is true regarding dot plots and histograms?

Dot plots do not lose the identity of individual observations.

Which of the following statements describe a feature of a scatter diagram? Select all that apply.

One variable is scaled on the horizontal axis and the other is scaled on the vertical axis Each paired observation is represented by a single dot

Each of the following is a measure of position in a set of data except:

Standard deviation

For a given data set, suppose Q1 = 40, Q2 = 45, Q3 = 50. Also, suppose that the three smallest observations are 20, 24, and 28. Which of the following is true about the box plot for this data set?

There would be two asterisks plotted to indicate outliers at 20 and 24.