Measures of dispersion

The range of a set of data is the:

• 1 Largest value minus the smallest value
• 2 Middle value
• 3 Average of the values
• 4 Sum of all values

The standard deviation is the:

• 1 Square root of the variance
• 2 Mean of the values
• 3 Square of the variance
• 4 Half the range

The variance of 2, 4, 4, 4, 5, 5, 7 and 9 is:

• 1 2
• 2 4
• 3 8
• 4 32

The standard deviation of the same data is:

• 1 4
• 2 2
• 3 5
• 4 16

The coefficient of variation is:

• 1 Mean / SD
• 2 (SD / mean) x 100
• 3 Range / mean
• 4 SD x mean

A mean of 50 and a standard deviation of 5 give a coefficient of variation of:

• 1 5%
• 2 50%
• 3 10%
• 4 25%

The quartile deviation is:

• 1 Q1 / Q3
• 2 Q3 + Q1
• 3 (Q3 - Q1) / 2
• 4 Q3 x Q1

Which measure is least affected by extreme values?

• 1 Mean deviation
• 2 Quartile deviation
• 3 Range
• 4 Standard deviation

The range of 3, 5, 7, 8, 9, 11 and 13 is:

• 1 10
• 2 16
• 3 8
• 4 13

A series with a smaller coefficient of variation is:

• 1 Impossible
• 2 More consistent
• 3 Always larger
• 4 Less consistent

Which measure of dispersion uses every value of the data?

• 1 Quartile deviation
• 2 Standard deviation
• 3 Mode
• 4 Range

The sum of the deviations of the values from their mean is always:

• 1 Zero
• 2 One
• 3 The variance
• 4 Positive