Measures of Dispersion

Question 1

What are the strengths and weaknesses of calculating range?

Answer 1

Strengths:
* Easy to calculate
* Useful to back up reliability of data

Weaknesses:
* Affected by extreme values
* Only tellus us about highest and lowest values, not all data in the set
* Does not tell us of the spread around the mean

Question 2

What do high/low standard deviations mean?

Answer 2

• High number shows a varied, wider spread of data
• Low number shows a consistent, narrow spread of data

Question 3

What are the strengths and weaknesses of calculating standard deviation?

Answer 3

Strengths:
* Precise measure of dispersion as it takes all values into account
* Not affected by extreme values
* Not difficult to calculate if you have a calculate

Weakness:
* May hide some characteristics of the data (e.g extreme values)