Excel is used extensively for statistical work, but does not support
specialized statistical characters. For example, the sample mean is usually
written as 'x' with a bar over it, or x-bar. The equation to approximate
regression is referred to as y-hat, the letter y with a caret (^) on top.
I believe inclusion of all of the specialized statistical symbols in the
character set would add in the presentation of statistical analysis done in
Excel.

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