Newsroom math

A few words about numbers and the problems they pose for editors

Newsroom math

There are all kinds of stories out there that require numbers. There are stories about test scores, surveys, political polls, census stories, demographics stories, nearly all sports stories. So now you have another problem – not only do you have to worry about the words, you have to make sure the numbers are right, too.

Numbers stories are kind of like the 3,000-meter steeplechase – you not only have to run nearly 2 miles but you have to overcome hurdles and a water pit as well.

A little math test …• How many times would you like to go out and have a

good time each week? Write down that number. (For me, that would be 2. That’s all I can afford.)

• Multiply the number above by 2 (4)

• Now add 5 (9)

• Multiply that number by 50 (450)

• If you have already had your birthday this year, add 1,759. If not, then add 1,758 (This is good for 2009 only; add 1 to those numbers if it’s 2010, etc.) (2,207)

• From this, subtract the year (1955) you were born in.

A little math test … the answer please

• You should end up with a three-digit number. (For me, 253)

• The last two digits should equal your current age. (Yes … sigh)

• The first digit should equal your answer in the first step – the number of times you want to go out and have a good time.

If you didn’t come up with that, it’s time to take your math skills in for a check-up.

Numbers: A style guide (handout)

• Mr. AP’s general rule is to spell out numbers from zero through nine and use numerals for numbers 10 and above. If it has two digits or more, make it a number!

• Some notable exceptions are millions, percentages, ages, years, headlines – always use numbers. But note that a headline that says “Fire consumes 3 5-story buildings” could be misread in some fonts as a row of 35-story buildings being destroyed.

• There are references to numbers throughout the AP stylebook, but many of them are under the dimensions entry.

• Note that you spell out “percent” in stories but can use the percent sign in headlines.

Budgets and math

Editing stories about government agencies will undoubtedly require that

you learn something about budgets. Nearly all governmental entities have budgets – that contain your money – and those budgets rarely stay the same. So you might have to do some math, particularly with percentages.

Budgets (Stanton handout)• Budgets are an estimate of money coming in and going out -- is

there a deficit?• Comparison needed to previous budget or budgets and to actual

figures• Fiscal years vs. calendar years• Where is budget shrinking or growing? A clue to political philosophy• With tax rates, give an example.

Some common math in journalism

• Average: add up the numbers in a series and divide by the sum of the numbers in the series. Example: 67 74 89 90 100 = 420. Divided by 5 gives an average of 84.

• Median: the middle number in a series that is arranged in ascending order. From the previous example, the median is 89. But in this series -- 67 74 83 89 90 100 -- the median is 86 (the midpoint between the middle two numbers, 83 and 89).

• Mean: the dividend between the highest and lowest numbers in a series or group. Using the first example: 67 + 100 = 167. Divided by 2 = 83.5.

Now you do it …

A basketball player scores 22, 15, 18, 13, 12 and 25 points over six games. What is his average in those six games?

What is the median score?

What is the mean?

The answers are …

Average is 17.5 (12 + 13 +15 + 18 + 22 + 25 = 105; divided by 6)

Median is 16.5 (12, 13, 15, 18, 22, 25; 15 + 18 divided by 2)

Mean is 18.5 (12 + 25 = 37, divided by 2)

Some common math in journalism• Percentages: The part divided by the whole x 100. Say

you have a city with 200,000 residents and 10,000 are jobless. What is the percentage of jobless folks?

10,000 divided by 200,000 = .05 x 100 = 5 percent.

• Percentage increase/decrease: Take the NEW number and subtract the OLD number, divide that result by the OLD number and multiply by 100. Using the previous example, let’s say the jobless figure grows to 15,000. The percentage of jobless becomes 7.5 percent. What is the percentage increase?

15,000 (new number) minus 10,000 (old) = 5,000. Divided by 10,000 (old) = .50 x 100 = a 50 percent increase

Newsroom math: Danger areas

• Percent and percentage points: In the previous example, note that the difference between 5 percent and 7.5 percent is 2.5 percentage points -- not 2.5 percent. That 50 percent increase translates to 5,000 human beings. This is where spin can come in: When talking about their record, which figure would a mayoral incumbent prefer to be used to describe the jobless numbers -- 50 percent, 5,000 or 2.5 percentage points?

Also, be aware that a 200 percent increase is not the same as “double.” It’s a 100 percent increase that is actually the figure that is twice the size of the previous number. A 200 percent increase is triple the original.

Newsroom math: Danger areas

• Spin or misleading numbers: Be aware that numbers can lie. (GET HANDOUT) There’s an old saying out there: There are lies, damn lies and statistics. That’s why in baseball they often say “tell your statistics to shut up.”

• Ages: Ages are a prime part of the identifier equation in news stories. Check against whatever database or archive you have. Publicdata.com is a good one. Note that people in Hollywood lie about their ages all the time. Age discrepancies often appear in obits; check the age against the date of birth.

• Box scores: Make sure the numbers add up, whether it’s the stats on the player or the final score. Make sure the numbers in the story and box score match.

Newsroom math: Danger areas

• Informational graphics: make sure the percentages add up to 100, or say why they do not (rounding). Make sure the numbers in the graphic match the story.

• Phone numbers, Web addresses: always check them.

• Dates and times: Check ’em, make sure they are correct. Make sure the date matches the day. Or, just make sure they are there if needed.

• Rounding: It’s OK to round off large numbers; you can use 1.2 million instead of 1,211,241, for instance. But be careful rounding to just two digits – rounding 1,662,000 up to 1.7 million leaves out almost 40,000 of whatever. Maybe it’s more accurate to round down to 1.66 million

Newsroom math: Danger areas

• “About”: The word about indicates an estimate follows. It’s not a total. Therefore, “totaling about” is an incorrect usage. Also, when an exact number is presented, it should never be preceded by “about.”

• Millions vs. billions: Often one becomes the other in stories. Or, is just missed altogether.

• Rates: A rate compares numbers against a common, unvarying base number, much like a percentage. Beware of saying the rate has gone up or down, just because the number did so. The base number – such as a population -- may have also changed over the same time frame, and that would affect the rate.

Newsroom math: Rates handout, example

A commonly used rate is a homicide rate, which is the number of homicides per 100,000 residents of a city.

Example: Houston’s population in the 2000 census was 1.95 million, so let’s round to 2 million. Let’s say 350 people were murdered in 2005. So …

350 / 2 million = .000175 x 100,000 = 17.5. Houston’s murder rate for 2005 would be 17.5 persons per 100,000 population.

If, when 2006 comes, the number of murders went up but the population also rose, the rate may actually decline:

360 / 2.2 million = .0001636 x 100,000 = about 16.4 persons per 100,000 population

Newsroom math: Tax rates

Government bodies get revenue from a variety of sources – grants, utility bills, franchise fees (such as cable TV), fines, user fees (parks), sales tax, bonds etc. But the primary source for most entities is from taxes levied on commercial and residential properties.

Texas law requires that the actual appraised value of the property, not some assessed value, be used in the property tax equation. County appraisal districts provide property values to all of the governmental bodies in that county. The government body -- a school board, city council, utility district, fire department district etc. -- sets a tax rate, which is then applied to every $100 (the base number) of the property’s appraised value. In your stories, the style for referring to tax rates is: The board approved a tax rate of $1.12 per $100 value.

More on tax rates

When doing stories about budgets and tax rates, provide the reader with an example of how the tax rate will affect the average homeowner. Appraisal districts can tell what the average price is for a home in a particular community.

Examples: Let’s say you have a $120,000 home in Katy

• Katy ISD tax rate is $1.10 per $100 value. 120,000 divided by 100 = 1,200 x 1.10 = $1,320 that you owe Katy ISD

• City of Katy tax rate is 95 cents per $100 value. 120,000 divided by 100 = 1,200 x .95 = $1,140 that you owe the city of Katy

Note that commercial and residential tax rates may differ. Also note that a variety of tax exemptions could reduce the amount owed.

Help with math

You might want to bookmark these Web sites:

• www.ibiblio.org/slanews/conferences/sla2005/programs/mathcrib.htm

• www.coolmath4kids.com (Go to the calculate this link)

Exercise

Fun with numbers

• Find the math or word errors (or questionable usage) in these 10 sentences. There is one bonus sentence.

• Note that the “error” may not be immediately evident (like an incorrect score); instead, it may be something that raises a question.

• All “errors” are derived from the “danger areas” listed in this lecture