standard deviation
What standard deviation means in Mathematics A-Level, as defined for AQA, Pearson Edexcel, WJEC.
Definitions of standard deviation
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Reference: WJEC
Measures root mean square spread about the mean, and a larger value means greater variability or lower consistency in performance.
A measure of how far values typically lie from the mean, in the same units as the data, calculated using division by n.
A measure of the spread of data around the mean, with a larger value indicating greater variability.
A measure of dispersion about the mean, defined as the positive square root of the variance.
A measure of typical spread from the mean; a larger standard deviation gives a wider Normal curve.
A measure of spread in the same units as the data; σ = √Var(X).
Topics that use standard deviation
- L: Data presentation and interpretation (AQA A-Level)
- N: Statistical distributions (AQA A-Level)
- Data presentation and interpretation (Pearson Edexcel A-Level)
- Statistical distributions (Pearson Edexcel A-Level)
- Data presentation and interpretation (AS Unit 2: Applied Mathematics A) (WJEC A-Level)
Related terms
- Frequency density
- Summary statistics
- Binomial distribution
- Cleaning data
- Correlation
- data cleaning
- Histogram
- interquartile range
Using standard deviation in the exam
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