The mean is the average of your set of data. Each data point in a set has a small difference or deviation between it and the mean. The standard deviation is the average of these small differences. It helps tell you how precise or tightly clustered your data is around the mean with a small value being more precise than a large one. If the average female height is 62 inches and the standard deviation is 3, one standard deviation is +/- 3 in either direction and two standard deviations are +/- 6 in either direction. We use the phrasing within one/two/X# standard deviations to scale probability calculations like Z scores...which is another lecture. Hope this helped. I recommend stat info from here. It's helped me in the past https://www.statology.org/find-probability-given-mean-and-standard-deviation/ Answer from msmsms101 on reddit.com
Statology
statology.org › home › why is standard deviation important? (explanation + examples)
Why is Standard Deviation Important? (Explanation + Examples)
August 4, 2021 - The answer: Standard deviation is important because it tells us how spread out the values are in a given dataset.
Dummies
dummies.com › article › academics-the-arts › math › statistics › why-standard-deviation-is-an-important-statistic-169731
Why Standard Deviation Is an Important Statistic
July 2, 2025 - Without calculating standard deviation, you can’t get a handle on whether the data are close to the average (as are the diameters of car parts that come off of a conveyor belt when everything is operating correctly) or whether the data are spread out over a wide range (as are house prices and income levels in the U.S.).
ELI5: someone please explain Standard Deviation to me.
I’ll give my shot at it: Let’s say you are 5 years old and your father is 30. The average between you two is 35/2 =17.5. Now let’s say your two cousins are 17 and 18. The average between them is also 17.5. As you can see, the average alone doesn’t tell you much about the actual numbers. Enter standard deviation. Your cousins have a 0.5 standard deviation while you and your father have 12.5. The standard deviation tells you how close are the values to the average. The lower the standard deviation, the less spread around are the values. More on reddit.com
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March 28, 2021ELI5: Standard Deviation
Standard Deviation is a measure of how much variation exists in a set of data. A low SD means that most of the data lies close to the mean (Mathematical Average). Example data (5,5,5,6,7,7,7) A High SD means that the data is more spread out. Example data (1,1,1,6, 11,11,11) Both have a mean (Mathematical Average) of 6, but the SD of the first is .93 and the second is 4.6. More on reddit.com
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March 26, 2014ELI5: What exactly does Standard Deviation (SD) helps us find in a cluster of data?
The mean is the average of your set of data. Each data point in a set has a small difference or deviation between it and the mean. The standard deviation is the average of these small differences. It helps tell you how precise or tightly clustered your data is around the mean with a small value being more precise than a large one. If the average female height is 62 inches and the standard deviation is 3, one standard deviation is +/- 3 in either direction and two standard deviations are +/- 6 in either direction. We use the phrasing within one/two/X# standard deviations to scale probability calculations like Z scores...which is another lecture. Hope this helped. I recommend stat info from here. It's helped me in the past https://www.statology.org/find-probability-given-mean-and-standard-deviation/ More on reddit.com
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November 23, 2022I still don't understand what standard deviation, even in grad school.
A lot of people using math terms, I'll try to explain better in non-math terms. Basically variance or standard deviations are a measure of how surprised you are to see numbers that are far away from the usual. So for example if you took everyone's age in the world, the average would likely be 40ish, just a random guess. But it's not super crazy to see people who are newborns or 80 years old. On the other hand say you're measuring the age of people in high school. You see a few people who are gifted who are younger, a few people who were held back or moved or whatever who are older, but the vast majority would be 13-17. How surprised would you be if someone told you there was a 55 year old high schooler? More surprised than an 80-year old human right? That's because the standard deviation for humans is much higher than the standard deviation for high schoolers. Once you get that, you'll need to start looking at the math, and probability distribution graphs, and understand how to calculate it. But hopefully this at least helps you with a real world example of understanding it. More on reddit.com
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January 14, 2023Videos
Biostatistics: Why Is Standard Deviation Important?
07:50
Standard Deviation - YouTube
03:43
Standard Deviation - Explained and Visualized - YouTube
Variance and Standard Deviation – The Most Important ...
Why Standard Deviation is Important when Investing ? | On ...
03:28
3 examples to understand how standard deviation is useful - YouTube
Reddit
reddit.com › r/explainlikeimfive › eli5: what exactly does standard deviation (sd) helps us find in a cluster of data?
r/explainlikeimfive on Reddit: ELI5: What exactly does Standard Deviation (SD) helps us find in a cluster of data?
November 23, 2022 -
I’ve been looking at Statistics in my free time and what exactly does standard deviation is useful for and/or how can I extract meaningful data by using SD and what conclusion can I derive from said data?
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The mean is the average of your set of data. Each data point in a set has a small difference or deviation between it and the mean. The standard deviation is the average of these small differences. It helps tell you how precise or tightly clustered your data is around the mean with a small value being more precise than a large one. If the average female height is 62 inches and the standard deviation is 3, one standard deviation is +/- 3 in either direction and two standard deviations are +/- 6 in either direction. We use the phrasing within one/two/X# standard deviations to scale probability calculations like Z scores...which is another lecture. Hope this helped. I recommend stat info from here. It's helped me in the past https://www.statology.org/find-probability-given-mean-and-standard-deviation/
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It's simply a measure of how close sample values are to their mean. If all sample values are the same, the standard deviation would be zero. If they're all close to the mean, the SD will be small. If the values are widely spread the SD will be correspondingly large.
Gustavodefelice
gustavodefelice.com › p › what-is-the-standard-deviation-and
What is the standard deviation and why is so important
July 31, 2023 - It is an essential tool in statistical analysis and helps to understand the dispersion and uncertainty within a dataset. Let's consider a simple example to understand standard deviation.
Statistics Easily
statisticseasily.com › home › exploring standard deviation: statistics and data analysis made easy
What is Standard Deviation Statistics and Data Analysis
December 11, 2023 - It plays a vital role in various fields and industries, helping professionals understand the variability of data, assess its reliability, and make informed decisions. However, it’s essential to be aware of its limitations and the importance ...
Greenbook
greenbook.org › insights › research-methodologies › how-to-interpret-standard-deviation-and-standard-error-in-survey-research
How to Interpret Standard Deviation and Standard Error in Survey Research — Greenbook
The distribution of responses is important to consider and the SD provides a valuable descriptive measure of this. Two very different distributions of responses to a 5-point rating scale can yield the same mean.
Vocal Media
vocal.media › education › what-is-standard-deviation-and-why-is-it-important-cx1sbn00g2
What Is Standard Deviation and Why Is It Important? | Education
1 month ago - Standard deviation is a powerful statistical tool that helps us understand variability in data. Whether you're comparing datasets, assessing risk, or identifying outliers, this simple calculation provides meaningful insights that go far beyond ...
The Journalist's Resource
journalistsresource.org › home › what’s standard deviation? 4 things journalists need to know
What's standard deviation? 4 things journalists need to know
October 5, 2022 - Since the standard deviation of a dataset takes into account how far away individual values are from the average, scientists often use it to gauge whether an unusual data point is an outlier.
EBSCO
ebsco.com › research-starters › mathematics › standard-deviation
Standard deviation | Research Starters | EBSCO Research
Both types assume a normal distribution ... deviation is crucial for interpreting statistical data and assessing variability in various fields, including finance, psychology, and social sciences....
Standard Deviation Calculator
standarddeviationcalculator.io › blog › the-importance-of-standard-deviation-in-data-analysis
The Importance of Standard Deviation in Data Analysis
If the standard deviation is small, it signifies that the data points tend to be close to the mean. Conversely, a high standard deviation indicates that the values are spread out over a wider range. The role of standard deviation becomes increasingly important when dealing with large datasets, complex analytics, and statistical modeling.
Testbook
testbook.com › home › mathematics › standard deviation
SAT Standard Deviation Definition, Significance, and Relationship With Variance
Standard deviation is significant as it measures deviation and volatility, which further prove very important in showing central tendency. It is used in both mathematical operations and statistical analysis.
Alooba
alooba.com › skills › concepts › python-16 › standard-deviation
Standard Deviation: Everything You Need to Know When Assessing Standard Deviation Skills
Statistical Significance: By analyzing standard deviation, we can determine the reliability or importance of data points within a given dataset.
Pearson
pearson.com › channels › statistics › learn › patrick › describing-data-numerically › standard-deviation
Standard Deviation Explained: Definition, Examples, Practice & Video Lessons
November 19, 2024 - The standard deviation (s) is a crucial measure of variation that indicates how spread out data values are around the mean. A higher standard deviation signifies greater dispersion. To calculate it, use the formula: 1(n-1)(∑x2-∑x)^2/n).
LinkedIn
linkedin.com › advice › 0 › how-do-you-determine-standard-deviation-significant-lcqne
How do you determine if a standard deviation is significant?
May 20, 2024 - We cannot provide a description for this page right now
National Library of Medicine
nlm.nih.gov › oet › ed › stats › 02-900.html
Standard Deviation - Finding and Using Health Statistics - NIH
A standard deviation (or σ) is a measure of how dispersed the data is in relation to the mean. Low, or small, standard deviation indicates data are clustered tightly around the mean, and high, or large, standard deviation indicates data are more spread out.
JMP
jmp.com › en › statistics-knowledge-portal › measures-of-central-tendency-and-variability › standard-deviation
Standard Deviation
The standard deviation measures the spread of a set of data values. Learn how to visualize it, calculate it, and use it to better understand your data.
Statistics By Jim
statisticsbyjim.com › home › blog › standard deviation: interpretations and calculations
Standard Deviation: Interpretations and Calculations - Statistics By Jim
September 24, 2025 - The standard deviation uses the original data units, simplifying the interpretation. For this reason, it is the most widely used measure of variability. Suppose a pizza restaurant measures its delivery time in minutes and has an SD of 5. In that case, the interpretation is that the typical delivery occurs 5 minutes before or after the mean time.
The BMJ
bmj.com › about-bmj › resources-readers › publications › statistics-square-one › 2-mean-and-standard-deviation
2. Mean and standard deviation
February 9, 2021 - The range is an important measurement, for figures at the top and bottom of it denote the findings furthest removed from the generality. However, they do not give much indication of the spread of observations about the mean. This is where the standard deviation (SD) comes in.
ScienceDirect
sciencedirect.com › topics › mathematics › standard-deviation
Standard Deviation - an overview | ScienceDirect Topics
The standard deviation is a number that summarizes how far away from the average the data values typically are. The standard deviation is a very important concept in statistics since it is the basic tool for summarizing the amount of randomness in a situation.
LeanScape
leanscape.io › home › lean wiki › demystifying standard deviation: a beginner’s guide
Demystifying Standard Deviation: A Beginner's Guide - LeanScape
Thirdly, standard deviation is the basis for other important statistical measures and concepts. For instance, the concept of Z-score or standard score, which measures the number of standard deviations a data point is from the mean, is based on standard deviation.
Published September 23, 2024