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What is considered a high standard deviation?

What is considered a high standard deviation?

For an approximate answer, please estimate your coefficient of variation (CV=standard deviation / mean). As a rule of thumb, a CV >= 1 indicates a relatively high variation, while a CV < 1 can be considered low. A “good” SD depends if you expect your distribution to be centered or spread out around the mean.

How do you know if standard deviation is large?

A large standard deviation, which is the square root of the variance, indicates that the data points are far from the mean, and a small standard deviation indicates that they are clustered closely around the mean.

Is a standard deviation of 5 high?

there is no value that is “high.” In one application I might expect a standard deviation that is close to zero no matter what the mean is. Here, I might be lucky if my standard deviation is less than five times my mean.

What number should standard deviation be?

The standard deviation must be zero, as the only way to average 5 is for everyone to answer 5. Conversely, if the mean were 1.0 then the standard error must be 0 as well. So the standard deviation is precisely defined given the mean.

What does a standard deviation of 3 mean?

A standard deviation of 3” means that most men (about 68%, assuming a normal distribution) have a height 3″ taller to 3” shorter than the average (67″–73″) — one standard deviation. Three standard deviations include all the numbers for 99.7% of the sample population being studied.

Is it better to have a higher or lower standard deviation?

A high standard deviation shows that the data is widely spread (less reliable) and a low standard deviation shows that the data are clustered closely around the mean (more reliable).

How to determine if standard deviation is high or low?

Your standard deviation would depend on your data size and application. I high standard deviation would mean that your data points seem to vary greatly from the mean while a low standard deviation tells you that your data points do not very greatly from the mean.

What does the standard deviation of a data set tell you?

The standard deviation is the average amount of variability in your data set. It tells you, on average, how far each score lies from the mean . In normal distributions, a high standard deviation means that values are generally far from the mean, while a low standard deviation indicates that values are clustered close to the mean.

What is the smallest standard deviation?

The smallest possible value for the standard deviation is 0, and that happens only in contrived situations where every single number in the data set is exactly the same (no deviation). The standard deviation is affected by outliers (extremely low or extremely high numbers in the data set).

How is the standard deviation affected by outliers?

Statistics For Dummies, 2nd Edition. The standard deviation is affected by outliers (extremely low or extremely high numbers in the data set). That’s because the standard deviation is based on the distance from the mean. And remember, the mean is also affected by outliers. The standard deviation has the same units as the original data.