Below is an example of calculating the standard deviation of the stock returns of Apple (Nasdaq: AAPL) over a three-month period. Step 1 : Collect daily data going back over a three-month period.

Example 12.1: Cusum and Standard Deviation Charts See CUSXS in the SAS/QC Sample Library When you are working with subgrouped data, it can be helpful to accompany a cusum chart for means with a ...

The normal distribution formula is based on two simple parameters—mean and standard deviation. ... The red horizontal line in both the above graphs ... Let’s see some real-life examples.

By default, the XRCHART statement estimates the process mean and standard deviation ()from the data, as in the previous example.However, there are applications in which standard values (and ) are ...