Deck 11: Quantiles and the Quartile Deviation

Question 1

When splitting a set up into quartiles, what name is given to the value that separates the highest from the second-highest quartile?

A) Upper Quartile
B) Median
C) Mean
D) Lower Quartile

Answer 1

Upper Quartile

Question 2

Using the quartile coefficient of dispersion, compare the information about petrol prices in Australia and Japan to see which has greater variance.

A) Australia
B) Japan
C) They are the same
D) You cannot tell

Answer 2

Japan

Question 3

Calculate the quartile coefficient of dispersion for data with a quartile deviation of 40 and a median of 95 (1 decimal place).

A) 41.7
B) 41.9
C) 42.1
D) 42.3

Answer 3

42.1

Question 4

Calculate the upper quartile for the following data set:

A) 2
B) 3
C) 4
D) 5

Question 5

Which statement about deciles is NOT true?

A) They split a data set up into 10 parts
B) D₅ is the median point
C) They are commonly used when discussing wages
D) Deciles have a tendency to misrepresent data

Question 6

Data for weekly sales total in a Dubai firm are analysed to give the following quartiles: Q₁ = AED 45,000; Q₂ = AED 52,500; Q₃ = 63,780. Which of the following options represents the correct interpretation of the quartile measure of skewness (qsk) for these figures?

A) qsk is positive, indicating a rightward skew
B) qsk is positive, indicating a leftward skew
C) qsk is negative, indicating a rightward skew
D) qsk is negative, indicating a leftward skew

Question 7

Quantiles split data into parts that are…?

A) Of equal frequency
B) Of equal skewness
C) Of equal variance
D) Of equal width

Question 8

Which statement about calculating quartiles is NOT true?

A) All the data values in a set lie within 1 quartile distribution of the median
B) In a simple frequency distribution, the quartiles are easily calculated
C) Quartiles can only be estimated for a grouped frequency distribution
D) The graphical method for estimating quartiles in a grouped frequency distribution is preferred

Question 9

Identify the lower quartile in this data set: 16, 24, 19, 10, 13, 19, 20

A) 10
B) 13
C) 19
D) 20

Question 10

New car sales values for March 2014 show that the lower quartile is £11,750, the median value is £16,360 and the upper quartile is £26,253. What is the value of the quartile distribution?

A) £7251.50
B) £14503.00
C) £16360.00
D) £19001.50