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Bernardo Augusto García Loaiza
Courses Plus Student 792 PointsWhat is the reason to get or reference three standard deviations?
Why in the normal distribution, we work with three standard deviations? Are they only three?
This is due to the property related to how many values occurr within one standard deviation in relation to mean? (this is referenced in the video ... )
Why take as a reference three standard deviations to address?
Is this one constant concept into normal distributions?
3 Answers
Jake Klein
13,262 PointsWe stop after 3 standard deviations because 99.7% of normally distributed data (i.e. data that fits a normal distribution) is within 3 standard deviations from the mean. This is a property of ALL normal distributions, which is one of the reasons why they're so useful. More on that can be found here:
https://en.wikipedia.org/wiki/68%E2%80%9395%E2%80%9399.7_rule
nafiz hassan
11,482 PointsCountif function in google sheets in showing an error message, "expecting 2 arguments but received 4 arguments". Any suggestions on how to get through this error.
Andrew Molloy
41,441 PointsYou should post as a new question. But I'm guessing you're using COUNTIF, when you should be using COUNTIFS.
nafiz hassan
11,482 PointsWill post as a new question next time and thanks got it