Statistics Every Writer Should Know

A simple guide to understanding basic statistics, for journalists and other writers who might not know math.

Interviewing DataNumbers can't "talk," but they can tell you as much as your human sources can. But just like with human sources, you have to ask!

So what should you ask a number? Well, mathematicians have developed an entire field - statistics - dedicated to getting answers out of numbers. Now, you don't have to have a degree in statistics in order to conduct an effective "interview" with your data. But you do need to know a few basics.

Here, described in plain English, are some basic concepts in statistics that every writer should know...



So, You're a Beginner?

Mean
   Let's get started...
Median
   How to find out how the "average Joe" is doing
Percent
   Ch-ch-ch-changes...

The Next Step: Not Getting Duped

Per capita and Rates
   When an increase is really a decrease and other ways people can use numbers to trick you
Standard Deviation and Normal Distribution
   A quick look at the King of Stats
Margin of Error and Confidence Interval
   How not to get suckered by polls and other research
Data Analysis
   How to tell if these numbers are really worth writing about anyway

Frequently Asked Questions

Sample Sizes
   "So how come a survey of 1,600 people can tell me what 250 million are thinking?"
Finding Data on the Internet
   "So where can I find the inflation rate, crime statistics, and other data?"
Statistical Tests
   "How do I pick the correct statistical test for me?"

Moving On

Student's T
   Is your sample relevant to the larger population it is supposed to represent? Use the t-test to find out.