# Math Tools

So much of the simple math we learn in middle school and high school is often cast aside and regarded as unnecessary for those of us aspiring to be writers or journalists. After all, how important are the formulas for finding distance, time and ratio when your writing features, right? But the success of a story often lies in the details. Skewed data, wrong numbers or just a general lack of information can severely discredit you as a journalist. Math skills are important whether or not we want to admit it it.

In her book, “Math Tools for Journalists,” Dr. Kathleen Woodruff Wickham discusses the importance of “directional measurements” and provides several quick and easy formulas for calculating simple math. Sometimes it is not enough to simply report an event. Readers want DETAILS. And statistics, polls, surveys, data, distances, times or rates can help a reader grasp the bigger picture.

Wickham also gives some tips on the accurate way to distinguish between speed and velocity and speed and acceleration. Speed measures rate, while velocity measures rate in addition to indicating direction. Acceleration is the “instantaneous speed.” Acceleration is a big word that indicates the increase or decrease of speed. Another easy, but important formula to remember is average speed.

Picture this: You’re reading your Sunday morning newspaper, sipping a cup of coffee when you stumble across an article claiming coffee drinkers are 70 percent more likely to contract cancer than non-coffee drinkers. You pour out your coffee and hasten to dispose of the remaining coffee in your kitchen – you will take no chances when it comes to your health.

But there is a problem with the article and the statistics the reporter used. Apparently, the scientists and researchers only observed 200 patients, 30 smoked, two lived near chemical plants and 18 were regular tanning-bed visitors. The researchers failed to mention this in their published research and a sloppy reporter used this information, failing to double check to be sure of accuracy.

This example is a little exagerated, but there are plenty of outliers and underlying factors that can skew a survey, observation, experiment or poll. As a journalist striving for fairness and accuracy in his or her reporting, it is imperative to make certain that your information is as infallible as possible. As humans we will make mistakes, but we should never fail to strive for 100 percent accuracy in our reporting.

In her helpful handbook, “Math Tools for Journalists,” Kathleen Woodruff Wickham devotes a chapter to polls and surveys. If used accurately, a poll or survey can add significantly to an article, but when used incorrectly it can hurt the reputation of the reporter and misinform readers.

Using Polls and Surveys Appropriately

You’re in a hurry. You have a deadline to meet. You need a survey for a story and http://www.crazysurVEYS.com is the first Web site you come across. You’re first instinct may be to quickly pull off some survey and the results and insert it into your story so you can submit the article on time. One of the simplest and most important things to consider is the foundation, organization or institute that conducted the poll or survey.

It is also wise to look up the person who paid for the poll, how recent is it? what was the demographic? how were questions worded?  what was the sample size?  what methods were used? what was the margin of error? These are all important things to consider.

If you’re striving for reliability, it is also important to check on the random selection process of the poll. Random selection means there was equal opportunity for anyone to take part in the poll.

A large sample is needed for a survey or poll when trying to represent a population. Pollsters strive for at least 400 participants for accuracy and an acceptable margin of error.

Margin of Error

500 random adults were polled on their political affiliations. 48 percent claimed to be Republican and 52 percent said they were democrat. Is it correct to say there were more democrats than republicans?

No. For a poll with 500 participants,  the confidence level is 95 percent and the margin of error is 4.4 percent.

Sarah Beth Costello
April 27, 2009

Graphic by Sarah B. Costello

MATH – it’s a small word, yet one that causes discomfort and even irrational fear in the hearts of many. For some math is a dreaded area of academia that seems relatively unimportant, especially for those pursuing a career in journalism.

Why would a reporter need to understand percentages, fractions or statistics right? Well it just so happens that basic math knowledge is very important. In fact, good math skills can make all the difference between a successful and not-so-successful career.

Dr. Kathleen Woodruff Wickham is the author of “Math Tools for Journalists” and understands the importance of math skills as a journalism professor at the University of Mississippi.

Journalists frequently take advantage of statistics. Statistics can strengthen an article, add clarity and specific information. But flawed or skewed data can severely hurt the reputation of a journalist. This is why it is important for journalists to possess an understanding of math in order to avoid basic mistakes.

Journalists often depend on other sources for data, but it is important to understand conversions as well.

For example:

The Red Hat Society had an annual budget of \$1500 in 2006. Due to a donation, the annual budget was raised to \$3500 in 2008. What percentage increase was the budget?

New figure: \$3500
Old figure: \$1500

3500 – 1500 = 2000
2000/1500 = 1.33 = 13 %

Sometimes, however, you will need to show a percentage decrease. This is also a very simple, yet important, formula.

Due to the recession, Truett Cathy, the owner of Chick-fil-a, decided to reduce his annual donation to Samaritan’s Purse from \$10,000 to \$3650. By what percentage was his donation reduced?

3650 – 10,000 = – 6350
– 6350/10,000 = – 63.5 %

Wickham points out that the context is always required so that readers can understand the numbers. Though \$1 million dollars sounds like hitting the jackpot, “if that \$1 million is just one percent of a city’s annual payroll, the figure doesn’t seem as big,” said Wickham. Calculating the percentage will enable your readers to understand your article and will put everything into perspective as well.

For example:

The North Carolina Train Museum spent \$257,456 repairing a 19th century locomotive. The entire budget of the museum is \$1 million. What percentage of the entire budget did the repairs consumer?

257,456/1 million = 25.7 %

Calculating Stats in Sports Writing

Have you ever seen a baseball card or attended a baseball game? Ever notice frequently used acronyms like “ERA” or “RBI” or heard the terms “batting average” or “slugging percentage?” Sports stats can get a little confusing, but as any baseball fan will attest, they are very important.

For instance, the batting average indicates the consistency of players to hit the ball. The average incorporates at-bats, subtracts the walks and the “number of times the batter was hit by the pitch.” Earned Run Average (ERA) measures a team’s score against a specific pitcher. The formula for this particular measurement is ERA = R(27/ip).

In this case, “R” represents the number of runs scored when a particular pitcher was on the mound. “Ip” represents the number of outs made during the pitcher’s time on the mound.

The ‘L’ word (Loans)

Whether making payments on a car, apartment or house, many consumers make monthly payments. Most people use advanced calculators when figuring out these detailed figures. But there is a formula, which ensures accuracy from journalists.

Example:

Bojangles bough a building for \$75,000. It financed the entire amount at 5 percent for the period of 12 years. What is the monthly payment?

A = [\$75,000 x 1 + .005) 120 (power) x .005]/[(1 + .005) 120 (power) – 1]