It seems that Microsoft Excel* doesn’t know how to average. Or am I missing something? I showed to the lab postdoc and we both we were wide-mouthed. How can I be confident that simple Excel commands are producing the correct results? This is pretty important since I am composing a table of mean abundances (per collection) for 55 species for nine factor levels for publication! The rest seemed OK, but I’ll need to spot-check on Monday to remain confident. How did I figure out there was a mistake? One cell had a mean that was an order of magnitude higher than should have been possible with my a priori knowledge. See the graphic below and tell me that it is just me and I’m flipping out for no reason. Tell me I’m wrong and I have nothing to worry about. I do consider myself pretty fluent in MS Office products.
* Microsoft Office 2004 for Mac OSX, with all necessary updates.