1
Q
How is SD useful for comparing the means and spread of data between two or more samples?
A
A small SD indicates that the data is clustered closely around the mean. A large SD indicates a wider spread around the mean
2
Q
What is the statistic used to summarise the spread of values around the mean?
A
about 68% of all values lie within one SD.
95% lie within two SDs of the mean
99.7% lie within 3 SDs of the mean
3
Q
Coefficient of variation formula
A
V = SD/mean X 100
4
Q
Benefits of the coefficient of variation?
A
Allows us to compare between different data sets, with different units.
SD only allows us to compare within units
