Measures of spread

​Measures of spread

Poll

Given the data set 3, 7, 8, 9, 15, What is the range?

• 18

• 15

• 12

• 3 - 15

Open Ended

Now consider the data set 3, 7, 8, 9, 100.
What is the new range and What can you conclude?

Multiple Choice

What is the range of a data set?

• The distribution of all values

• The sum of all values

• The difference between the highest and lowest values

• The spread of the middle 50%.

Multiple Choice

Why is the range important in analyzing data?

• It shows the consistency of the data points

• It highlights the variation between the highest and lowest values

• It eliminates outliers from the data set

• It calculates the mean

Multiple Choice

Find the range of the data.

63, 71, 65, 66, 87, 53

• 32

• 33

• 34

• 35

Multiple Choice

What is the range?

• 10

• 12

• 14

• 2 - 12

​Quartiles

​The position of lower and upper quartiles

Multiple Choice

33, 25, 42, 25, 31, 37, 46, 29, 38
What is the third quartile (UQ) of the data?

• 37
• 38
• 40
• 46

Multiple Choice

1-  The first quartile (Q 1) is the median of the lower half of the set.
2-  The second quartile (Q 2) is the median of the whole set .
3-  The third quartile (Q 3) is the median of the upper half of the set.

• All three statements are true.
• Only the 1st statement is true.
• Only the 2nd and the 3rd statements are true.
• Only the 3rd statement is true.

Multiple Choice

Find the lower quartile of the following set of scores: 12, 9, 4, 6, 5, 8, 9, 4, 10, 2

• 10
• 4
• 9
• 6

Open Ended

Write down one positive aspect of the interquartile range as a measure of spread.

Multiple Choice

Find the interquartile range using the following.
Minimum:  1
Q1:  3
Median:  5
Q3:  7
Maximum:  9

• 8
• 4
• 5
• 10

Multiple Choice

What is the interquartile range of the data set below?

3, 5, 6, 6, 7, 8, 9

• 3

• 6

• 2

• 8

Multiple Choice

Find the IQR using the following data.

50, 60, 82, 86, 94, 110

• 60

• 84

• 34

• 50

Multiple Choice

Two classes have test scores as follows:

Class A: 70, 75, 80, 85, 90

Class B: 65, 69, 72, 80, 82

Which class has more consistent scores?

• Class A

• Class B

• Both classes are as consistent

• None of the classes are consistent