Chapter 2: Measures of Location and Spread

Question 1

How is the mean for data given in a frequency table calculated?

Answer 1

sum of products of the data values and their frequencies divided by the sum of the frequencies

Question 2

How can you determine the lower quartile for discrete data?

Answer 2

Divide n by 4. If this is a whole number, the lower quartile is halfway between this data point and the one above. If it is not a whole number, round up and pick this data point.

Question 3

How can you determine the upper quartile for discrete data?

Answer 3

Find 3/4 of n. If this is a whole number, the upper quartile is halfway between this data point and the one above. If it is not a whole number, round up and pick this data point.

Question 4

How are the quartiles for grouped continuous data found?

Answer 4

Q1 = n/4 Q2 = n/2 Q3 = 3n/4

Question 5

Explain how the mean and standard deviation of coded data is found.

Answer 5