One of the grand difficulties in debating any issue, especially sitting around a few beers with peers, is the use of studies people have read and numbers people have heard. It is infinitely grating to me when this happens. I just finished reading another evaluation of a recent study of proximal intercessory prayer, and I felt I needed to comment. I don’t want to comment on the study itself, as it has been commented in detail by Steven Novella and PZ Myers, and I’m sure I’ve read comments from others that I simply can’t remember right now. Instead, I’ll comment on the overall use of studies and numbers in argument, and it will be merely my own random thoughts, and not some detailed screed expressing any kind of exacting science. So don’t quote this in conversation sitting around a few beers with peers.

First off, I want to address the term “average”. It amazes me how often that term is absolutely abused in conversation. People will say things like, “Well, your average American thinks Obama’s doing a terrible job” without having any reference to what the average American is. People will say things like “On average, I’d say the economy is doing well” but have no mathematics to back that up. Average is a mathematical concept. In my statistics class, we learned that there were different mathematical formulas that all wound up under the heading of average. We focussed primarily on median, mode, and arithmetic mean, but there is also geometric mean and harmonic mean. All of these concepts when applied to a given data set will yield different results. The arithmetic mean (the formula we most commonly associate with average) is where you add up all the numbers and divide by the number of results. The median is the middle value of the data set when it is sorted. The mode is the most commonly occurring number in a data set. For example, using the data set 2, 9, 1, 9, 6:

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