2.1 Measures of central tendency

Question 1

What is a measure of location?

Answer 1

» A single value which describes a position in a data set

Question 2

What is the measure of central tendency?

Answer 2

» If the single value describes the centre of the data

Question 3

What is mode/ modal class?

Answer 3

» Values or class which occurs most often

Question 4

What is the median?

Answer 4

» Middle value when the data values are put in order

Question 5

How can the mean be calcuated?

Answer 5

x bar = Sigma x / n

Question 6

What does x bar mean?

Answer 6

» The mean of the data

Question 7

What is Sigma x?

Answer 7

» Represents the sum of the data values

Question 8

What is n?

Answer 8

» The number of data values

Question 9

When can we use mode to describe particular situations?

Answer 9

» When data is qualitative or quantitative with either a single mode or 2 modes
» Not very informative if each value occurs only once

Question 10

When can we use median to describe particular situations?

Answer 10

» Used for quantitative data
» Used when there are extreme values, as they do not affect the medium

Question 11

When can we use mean to describe particular situations?

Answer 11

» Used for quantitative data nad uses all the pieces of data
» Gives true measure of data
» But can be affected by extreme valyes