Deck 9: Measures of Dispersion and Skewness

Question 1

Which measurement of a data set gives information about whether data is distributed symmetrically?

A) Location
B) Dispersion
C) Skewness
D) Reliability

Answer 1

Skewness

Question 2

Calculate the mean deviation for the following set of data: 2, 8, 3, 1, 5, 6, 3

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

Answer 2

2

Question 3

Which of these statements relating to skewness is NOT true?

A) The direction of the skew is determined by the long tail of the distribution
B) We expect salaries to have a left skew
C) The direction of skew can be seen by comparing the mean and mode
D) The size of the difference between mean and mode gives an indication of how skewed the data is

Answer 3

We expect salaries to have a left skew

Question 4

Which of these statements about the range IS true?

A) It is often used in advanced statistical analysis
B) It is not affected by extreme high or low values
C) It is easy to calculate and understand
D) It cannot be easily charted

Question 5

A corner shop makes a note of the number of shopping bags used by customers during the course of one day. The following frequency distribution is produced [number of bags(frequency)]: 0(8); 1(26); 2(24); 3(6); 4(1). Calculate the mean deviation (2 decimal places).

A) 1.48
B) 0.63
C) 1.25
D) 0.75

Question 6

Which measurement of a data set gives information about how spread out the data is?

A) Location
B) Dispersion
C) Skewness
D) Reliability

Question 7

Which base for measuring the spread of data is associated with the median?

A) Range
B) Standard Deviation
C) Quartile Deviation
D) Mean Deviation

Question 8

A bookshop records how many copies of a Statistics textbook are sold each day for a week. The results are: 4, 5, 1, 2, 0, 8, 5. What is the range of this set of data?

A) 5
B) 3.6
C) 8
D) 4

Question 9

Which of the following statements about the mean deviation is NOT true?

A) The mean deviation is useful for comparing data sets that are similar
B) The mean deviation is easy to handle theoretically and commonly used in further analysis
C) It can be awkward to calculate if the mean is not a whole number
D) The mean deviation must always be calculated using absolute value of values in the data set

Question 10

When calculating a mean deviation for a grouped frequency distribution which value should be used in the calculation?

A) Lower bound
B) Upper bound
C) Midpoint
D) Width