BRAINCAKEMean and Standard Deviation
The standard deviation measures the spread of data around the mean. A small standard deviation means the values are close to the mean; a large standard deviation means they are more spread out.
It is more useful than the range because it uses every value and is less affected by a single outlier.
The standard deviation of a sample is calculated using:
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Key terms in this lesson
- error bars
- Lines added above and below a plotted mean on a graph to show the spread of the data used to calculate it, for example the range or plus and minus one standard deviation.
More in Biodiversity
- Sampling
- Random Sampling
- Normal Distribution
- Mean, median and Mode
- Interpreting Graphs 1
- Interpreting Graphs 2
- Interpreting Graphs 3
- Interpreting Graphs 4
All 33 lessons in Biodiversity · All AQA AS-level Biology topics