Standard Deviation vs. Variance: What’s the Difference?
Variance: An Overview Standard deviation and variance are two basic mathematical concepts that have an important place in ...
Investopedia10 年
What Does Standard Deviation Measure in a Portfolio?
Example of Using Standard Deviation Suppose a mutual fund achieves the following annual rates of return over the course of five years: 4%, 6%, 8.5%, 2%, and 4%. The mean value, or average ...
Simon Fraser University7 年
Example 43.2: Specifying Standard Values for the Process Mean and Standard Deviation
title 'Specifying Standard Process Mean and Standard Deviation'; symbol v=dot c=salmon; proc shewhart history=tape; xrchart weight*sample / mu0 = 1260 sigma0 = 15 xsymbol = mu0 cframe = bigb cinfill = ...
Simon Fraser University7 年
Example 42.2: Estimating the Process Standard Deviation
The following data set (WIRE) contains breaking strength measurements recorded in pounds per inch for 25 samples from a metal wire manufacturing process. The subgroup sample sizes vary between 3 and 7 ...
来自MSN25 天
Pooled Standard Deviation: How Do You Calculate It?
When you have the average production of three machines, it is easy to calculate the average or mean production. You just add up the three means and divide by three. But what if I want the average ...
BBC4 年
Statistical skills: Video playlist
An example involving zoo keepers and some very dangerous animals demonstrates that even with the same mean, median and mode, samples can differ greatly. How to calculate standard deviation using ...