Standard Deviation

Question 1

What is “standard deviation?”

Answer 1

• Spread of data about the mean value.

Question 2

Why is standard deviation more useful than calculating the range of data? 3 main reasons!

Answer 2

1.) SD shows spread of data from the mean, whereas, range is only difference between the highest/ lowest value.
2.) SD reduces the effect of anomalies whereas, range includes anomalies.
3.) SD can be used to indicate whether a difference between results is significant.

Question 3

Why would standard deviation be useful for making a conclusion from data?

Answer 3

• Overlaps between SD, shows that there is likely to be significant difference between the mean values.
• No overlap between SD shows that it is likely there is NO significant difference between the mean values.