Statistics every writer should know

• Mean, more vaguely called average value
• Median, the middle most value in a population or sample
• Mode, the most common value in a population or sample
• Percent of a population or changes
• Standard Deviation and Normal Distribution
• Margin of Error and Confidence Interval
• Data Analysis, at the very least knowing whether where the data comes from, and whether it was peer-reviewed

After
http://www.robertniles.com/stats/

Unfortunately, I still have not found out whether the way I calculated my so called "cumulative average" in the Everything Statistics on May 9, 2000 and beyond, is statistically correct. Google searches for "cumulative average" and "cumulative mean" have drawn blanks. Everythingians?

Update May 13, 2000. My discussions with /dev/joe leads me to understanding weighted average, a version of which is wa7 that I now use in the daily Everything Statistics since May 12, 2000. Thanks /dev/joe.

Update December 1, 2000. Revised median and mode. Thanks SgtCoolGuy.