Transcript Polls, Surveys and Statistics

Polls, Surveys and
Statistics
Reading, Reporting and Editing
Numbers in Journalism
“There are lies,
there are damn lies,
and there are statistics.”
- Benjamin Disraeli
Polls, Surveys and Statistics
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What is the purpose?
When do we use them?
Where do we get the information?
How do we use them?
Why do we use them?
Are they important in agricultural
news coverage?
Examples…
Surveys and Polls
• Why are surveys used?
– to gather information and opinions on
the issues of the day.
• How are surveys used?
– Prediction, change, proof
– Examples…
• What types of surveys do the media
use?
– Polls, sampling of readers, etc.
Editing Stories with Numbers
• Sources
– Who are the participants?
– Who sponsored the survey?
– Know whom you are dealing with.
• Sample
– How many people were questioned?
– Whom do they represent?
Editing Stories with Numbers
• Sample
– Systematic or stratified sample
– Increases reliability
– Divide respondents into specific groups
•Age
•Marital status
•Gender
•Party affiliation
•Education
•Location
•Income
•Ethnicity
Editing Stories with Numbers
• Margin of Error
– Opinion surveys
• Plus or minus percentage points
• Example – candidate is leading the polls 52
percent to 48 percent with a margin of error
of +/- 4 points. What can we report?
– Scientific study
• Confidence level
– What is the probability that the results are due to
chance?
– .95 confidence level, So what?
Be Skeptical
• How do you know?
• Have you done a study?
• Compared to what?
– Other studies
– Consistent results
Checking the Numbers
• Calculate percentages 15/60 * 100
• One out of: 60/15 = 1 out of 4
• More than vs as much
– $10,000 building purchased for five
times more than it is worth, what price
did you pay?
– $10,000 building purchased for five
times as much as it is worth, what price
did you pay?
Checking the Numbers
• Increase or decrease
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Increased to 6 percent from 1 percent
Increased from 1 percent to 6 percent
Decreased to 1 percent from 6 percent
Decreased from 6 percent to 1 percent
• More than or Less than
• Be aware of rounding
• Percent Change
increase to 6 – from 4 = 2
2/4 = .5 *100 = 50 percent increase
Checking the Numbers
• Percentages should equal 100.
– Round to a single decimal
• Percent increase vs. Percentage points
– Government spending increases to 20
percent of the budget from 10 percent, that
is a 10 percentage point increase or 100
percent increase.
20-10 = 10/10 = 1*100 = 100 percent