Science confirms: Politics wrecks your ability to do math

[xchrom]

http://grist.org/politics/science-confirms-politics-wrecks-your-ability-to-do-math/

?w=470&h=313

Let’s start with the “skin cream” version of this brain twister. You can peruse the image below to see exactly what research subjects read (and try out your own skill at solving it), or skip on for a brief explanation:

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As you can see above, the survey respondents were presented with a fictional study purporting to assess the effectiveness of a new skin cream, and informed at the outset that “new treatments often work but sometimes make rashes worse” and that “even when treatments don’t work, skin rashes sometimes get better and sometimes get worse on their own.” They were then presented with a table of experimental results, and asked whether the data showed that the new skin cream “is likely to make the skin condition better or worse.”

So do the data suggest that the skin cream works? The correct answer in the scenario above is actually that patients who used the skin cream were “more likely to get worse than those who didn’t.” That’s because the ratio of those who saw their rash improve to those whose rash got worse is roughly 3 to 1 in the “skin cream” group, but roughly 5 to 1 in the control group — which means that if you want your rash to get better, you are better off not using the skin cream at all. (For half of study subjects asked to solve the skin cream problem, the data were reversed and presented in such a way that they did actually suggest that the skin cream works.)

This is no easy problem for most people to solve: Across all conditions of the study, 59 percent of respondents got the answer wrong. That is, in significant part, because trying to intuit the right answer by quickly comparing two numbers will lead you astray; you have to take the time to compute the ratios.

[SheilaT]

1. I actually did the math,

although when I simply added up the totals of the two groups I knew which way it would turn out.

Even though on one hand this is a simple math problem, involving only addition and division, it's also a form of a statistics problem.

It really is scary how little very basic math most people cannot do.

[hfojvt]

2. one thing it seems to verify though

is intellectual laziness. People in the study may not CARE if they get the answer right or wrong. What is their incentive to do the work of these calculations?

What if they were given an incentive?

If, for example, they were given ten such problems and were PAID $5 for every correct answer and lost $5 for every wrong answer.

Would more people then do the work, and cast the poltics aside in order to get the money?