Harmonic or Arithmetic Mean?: I'm trying to settle an argument with my wife - is using the arithmetic mean or harmonic mean more appropriate when finding the "average" number of, say, online comments made by a large number of people, where a significant portion of them make only one comment and a few people make the bulk of the comments? [more inside]
posted by salsamander on Jun 2, 2012 - 13 answers

Please provide me with an *effective*, and statistically sound, table/chart listing suggested sample size guidance for associated population size [more inside]
posted by thankyoumuchly on Jan 14, 2010 - 11 answers

MathFilter: When you take the average of a series of ratios expressed as fractions, you get the same result whether you add together all of the fractions, then divide them by the size of the series or divide the sum of all of the numerators by the sum or all of the denominators. What's this called, and what's the formal proof for this look like? [more inside]
posted by ignignokt on Oct 29, 2008 - 14 answers

Grading dilemma: Can the median be a fair measure of a set of quiz scores? Here's the situation ... [more inside]
posted by imposster on May 8, 2006 - 24 answers

Remedial weighted averages for the mathematically illiterate – or, can the 10% of you who understand math help the remaining 95% of us who don't? [mi]. [more inside]
posted by RavinDave on Jul 11, 2004 - 3 answers