Answered

The following dotplot shows the number of songs on each album in Sal's collection. Each dot represents a different album.
A dot plot with an axis labeled "number of songs" and numbered from 0 to 20 in increments of 1, with 19 points. 4, frequency 1. 7, frequency 1. 8, frequency 2. 9, frequency 2. 10, frequency 4. 11, frequency 1. 12, frequency 2. 13, frequency 2. 14, frequency 1. 16, frequency 1. 18, frequency 1. 20, frequency 1.
Here is the five-number summary for these data:
Five-number summary
min \text{Q}_1Q
1
​
start text, Q, end text, start subscript, 1, end subscript median \text{Q}_3Q
3
​
start text, Q, end text, start subscript, 3, end subscript max
444 999 101010 131313 202020
According to the 1.5\cdot \text{IQR}1.5⋅IQR1, point, 5, dot, start text, I, Q, R, end text rule for outliers, how many high outliers are there in the data set?
Choose 1 answer:

Answer :

Using the quartiles of the data-set, it is found that there is one high outlier in the data-set.

What are the median and the quartiles of a data-set?

  • The median of the data-set separates the bottom half from the upper half, that is, it is the 50th percentile.
  • The first quartile is the median of the first half of the data-set, which is also the 25th percentile.
  • The third quartile is the median of the second half of the data-set, which is also the 75th percentile.
  • The interquartile range is the difference between the third quartile and the first quartile.

The dot plot shows the frequency of each observation, hence the complete data-set is given by:

4, 7, 8, 8, 9, 9, 10, 10, 10, 10, 11, 12, 12, 13, 13, 14, 16, 18, 20.

The quartiles are found as follows:

  • The first half is composed by the first 9 elements, given by 4, 7, 8, 8, 9, 9, 10, 10, 10, hence Q1 = 9.
  • The second half is composed by the last 9 elements, given by 11, 12, 12, 13, 13, 14, 16, 18, 20, hence Q3 = 13.

The IQR is given by:

IQR = Q3 - Q1 = 13 - 9 = 4.

The high outliers are the values that are more than 1.5 IQR above Q3, hence the threshold is given by:

13 + 1.5 x 4 = 19.

There is only value greater than 19, which is of 20, hence there is one high outlier in the data-set.

More can be learned about the quartiles of a data-set at https://brainly.com/question/3876456

#SPJ1

Other Questions