1. Background and Motivation
For those of you who were ripped off in your high school education, a brief review of an important symbolic convention is given here. This convention will be used in the formulae that you will need to use.
The capital Greek Sigma, , means sum or add. For example, suppose that you have 5 data sample values, represented abstractly by and , or more abstractly (using set notation) by:
, (or )
If you want to add the 5 values you would write:
Sometimes people get lazy and leave off the limits on the summation sign and write
where it is hopefully clear that is the summation index . We can also leave off the summation index and write
just to remind us that we need to add up a bunch of numbers generically represented by . This last convention is useful for us because whenever we need to deal with a sum in a formula, we will get that sum from adding up numbers in a table that we have constructed.