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Data Science & Analytics vocabulary · Statistics for Analysis

Standard deviation

Meaning in data science & analytics, with examples

nounCore term

In data science & analytics, standard deviation means: A measure of how spread out values are around the mean: a small value means most values are close to the average, a large one means they vary a lot.

In Turkish: standart sapma

How it is used

Often written as SD, std or the Greek letter sigma (σ). You calculate or report the standard deviation, usually next to the mean. 'Two standard deviations above the mean' is a common way to describe unusual values.

Example sentences

  1. Delivery times have a mean of three days and a standard deviation of half a day.

  2. Anything more than three standard deviations from the mean is flagged for review.

Common collocations

  • calculate the standard deviation
  • high standard deviation
  • one standard deviation
  • mean and standard deviation
  • meanThe value you get by adding all the numbers in a group and dividing the total by how many numbers there are; the usual meaning of 'average'.
  • distributionThe way the values of a variable are spread out, showing which values are common, which are rare and how far apart they are; often viewed as a histogram.
  • outlierA value that is very far from most of the other values in a dataset, for example one order of 50,000 dollars among orders of around 40 dollars.
  • confidence intervalA range of values, calculated from sample data, that is likely to contain the true value; a 95% interval comes from a method that captures the true value 95% of the time.

This word in other fields

The same English word can have a different meaning in another field:

More terms: Statistics for Analysis

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