Mr. Math Generator
A review of some terms and concepts with which many journalists struggle.
Concepts
Mean
All the data points added up ÷ Number of data points
So if your data is:
1
2
3
4
5
The mean is (1 + 2 + 3 + 4 + 5)/5 =
15/5 =
3
Median
The value in the middle of your data set
So if your data, from lowest to highest is:
1
2
3
4
5
The median is the data value in the middle, which is 3. If the length of the data set is an even number, then the median is the mean between the two in the middle.
So if your data, from lowest to highest is:
1
2
3
4
The median is the mean of 2 and 3, which is 2.5.
Calculators
Percentage
(Part ÷ Whole) X 100
Calculate your own percentage
÷ X 100 =
Amount of change
New - Old
Calculate your own amount of change
- =
Percent change
((New - Old) ÷ Old) X 100
Calculate your own percent change
( - ) ÷ =
Per capita
Total amount ÷ Total population
Calculate your own per capita
÷ =
Per 10,000 residents
(Total amount ÷ Total population) X 10,000
Calculate your own per 10,000 residents
÷ X 10,000 =
Comparisons
Often as journalists, we need to take abstract figures and compare them to something more concrete, like "the forest fire consumed 25 square miles, an area the size of Salina, Kansas." It can be hard to come up with those comparisons, though. So type in your number below, and we will give you some ideas.
Calculate your own comparison
SOURCES: Robert S. Davis, The Washington Post; Reuben Stern, Missouri School of Journalism; Robert Niles