Analytical - web analytics for blogmasters

Much of the analysis that a blogger or webmaster has to do on their web traffic and revenues depends on summing a set of numbers, and sometimes averaging the sum. Just as a point of review, I’d like to go over the basics of sums, and some of the notations that are used.

Terms:

1. Data set = a collection of numeric values.
2. Sum = summation = total. Given a data set of numeric values, produce the sum.
3. Sigma = ∑= a Greek letter which, in uppercase form, is used to denote a summation of terms. I’ll use the sigma notation a fair bit, as it provides a convenient short form for summation formulas. For example, if we have a set, A of 100 values (a₁..a₁₀₀) and we want the sum of the first 10, we might write ∑a_{i (i=1..10)} = a₁ +a₂ +a₃ +a₄ +… +a₁₀ = S(1,10). This isn’t standard math notation, and is only being used because we’re dealing with writing using a blogging platform.
4. N = the number of terms to be summed. Note that this could also be M or some other variable, but N is more traditional. N is also known as the “count” or “size” of the data set.

Any other mathematical/ statistical terms to be used will be covered when necessary.

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