Threads from Henry's Web

Tag: CNN

  • Polls and Headline Writing

    Margin of error
    Image via Wikipedia

    . . . or how to lie with headlines.

    I get very annoyed with the reporting of polls. One way to create news is to incorrectly headline or even incorrectly describe polling data.

    For example, CNN uses the headline Poll: Romney & Gingrich Tied for Top Spot in reporting on the latest USA Today/Gallup poll regarding the Republican presidential race. In the text they explain that Romney and Gingrich are at 20% and 19% respectively, that this is well within the margin of error of the poll (+/- four percentage points), and is thus essentially a tie. The number part of this is essentially correct.

    Then they say that Cain is following close behind, but they don’t point out at this point that Cain’s 16% is also within the sampling error of both of the leading candidates, or rather, that the probable range of Cain’s percentages largely overlaps those of the leading two candidates.

    The margin of error provides a range within which the real percentage of the whole population is likely to fall. If you go to the Gallup site for this poll you’ll find that the confidence level is 95%, in other words, there is a 95% probability that each candidates percentage of the real population falls within +/- 4 percentage points of the poll’s result. Thus there is a 95% change that Cain’s percentage is between 12% & 20%, that Gingrich’s is between 15% & 23%, and that Romney’s is between 16% & 24%.

    If you’re wondering why the polls seem to swing quite a lot among the leaders, this would be your explanation. If in a future poll, the number varies by less than four percentage points, that number would not necessarily reflect any change in that particular candidate’s support.

    Essentially, the news writers can produce the story they want. It’s possible (though with multiple polls showing him dropping, it’s not likely) that Cain could still be leading this.

    Now this particular headline may seem minor. But if you examine the headlines after just about any poll you’ll find that different news services spin the results differently, and that by reading the headlines and the first few paragraphs, you’ll get a somewhat different picture than you would if you read to the end of the story, or even better, go to the source of the poll.

    In this story, while we are told that the difference between Romney and Gingrich falls “well within the poll’s sampling error” in the second paragraph, we don’t find the actual margin of error (+/- four percentage points) until the very last sentence. At that point, if we look back, we can see that Cain is also within that margin of error, or rather that the intervals of all three top candidates overlap considerably.

    (For a write-up on this, see the Wikipedia article Margin of Error.)

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  • Is Civility Our Greatest Need?

    In the wake of the shootings in Tucson, much of the conversation has been about civility. I was just watching CNN as Wolf Blitzer interviewed Sheriff Dupnik of Pima County, Arizona. The sheriff was asserting that the caustic atmosphere created by people making caustic political comments contributed to making Jared Loughner go out at shoot a congresswoman and a number of other people. Pressured by Blitzer, he admitted he had no hard evidence but said that’s his opinion as a veteran of law enforcement, I believe 43 years.

    Personally I get a bit nervous when someone can’t present any evidence or logic, and yet they cite their opinion based on experience. I think that if experience teaches you something you ought to be able to express it. Of course, it may be that Sheriff Dupnik is correct. The problem is that we don’t actually know that.

    Now considering that I regard civility as extremely important, why do I think this is important? Why don’t I just rejoice that people are focusing on civility as a result of this event? The reason is simple–accuracy.

    I recall listening to a hearing some years ago in which a candidate for Surgeon General was being questioned by a senate committe working on his confirmation. One of his claims to fame was a particular program to prevent teen pregnancy. One of the conservative senators asked the candidate whether the evidence showed that this program had actually prevented teen pregnancies and how many. When it came time for Senator Edward Kennedy to question the candidate he expressed dismay at that question. I was left to wonder just why it was wrong to ask for evidence of the success of a program.

    Now as I recall I liked the candidate in question, and I felt some of the questioning from conservative senators was less gracious that it should have been. Yet that was a question for which I would have liked an answer. Why? Again–accuracy. We need to know what government programs are actually accomplishing.

    And this remains my concern about the calls for civility. Yes, civility is necessary, but so is accuracy. Let’s say two candidates, A & B, produce negative ads. Given the state of political advertising, it’s highly likely that both sets of ads are inaccurate, but that’s another matter. Few people care about the accuracy of positive ads. There will be a certain amount of voter negative response because both candidates have
    “gone negative.” But evidence shows that some of the mud will stick, so candidates get value from negative ads.

    But are both candidates A & B wrong for going negative? Let’s suppose that candidate A knows something about candidate B that actually calls B’s suitability for office into question. Should A not let voters know about this? I would say that A should let people know, though he should do it accurately. Thus when candidates “go negative,” my first response is to ask two questions: 1) Is the negative information true? and 2) Is the negative information relevant? In a voting decision I’d also ask whether A has enough positives, but I ask that regarding any candidate.

    The problem, as I see it, is that we give equal weight to information being negative without first inquiring as to whether it is accurate. There are candidates who are unqualified for office. There are candidates who are morally unsuitable. If that is the case, we should be able to discuss it. I would prefer this be done by energetic and accurate media, but absent such journalism, I have no problem with the candidates doing so.

    Doubtless we will disagree as to what is a valid criticism and what is not, but again, that is the nature of political debate. In addition, I think we should do our best to present such accusations in the most civil, careful, and accurate manner possible.

    Yes, I think civility is important, but if we took more care with accuracy, I think much civility would be restored. Thus I think accuracy is a more important goal.

     

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