How to Flip Ten Heads in a Row

            You say its cold out today. I disagree, it is merely brisk. Subjective descriptions can be vastly different because of the multitude of factors influencing them. However, we can both agree that the temperature is 18^o. Numbers are great in this way, because they can describe things objectively. But objective descriptions are still manipulatable by context. As in the previous example, I could also say that it was -8^o, and again that would be absolutely true. The difference is in what units of measure I am using to describe the temperature. Context is crucial to interpreting a statement, as what may be true may not also be meaningful in the present situation.

            One of my favorite examples is the following: I can flip a coin, and have it land heads up ten times in a row. Now, this isn’t a trick coin or some special flipping technique, anyone could replicate this. So hopefully at this point your thinking: “Impossible! I learned statistics in school. I know that the probability of an event is the number of outcomes that describe that event divided by the total number of possible outcomes.”

You are correct. In this case if you flip a coin ten times, the number of total events is 1024, of which only one of those describes a coin landing heads up all ten times. That is a probability of roughly one tenth of a percent. But I said I could get ten heads in a row. The key point is in what I did not say. I did not say I would only be flipping the coin ten times. In fact, I would have to flip the coin 2046 times on average, but eventually I would come up with ten heads in a row.

Context is everything. Research has come a long way in improving internal validity, that is how well data describe the actual effect of an intervention. But reporters often overlook external validity, that is how well do the data describe subjects other than the research participants. So, when they say dark chocolate or wine is good for you. Remember that the “you” they are referring to might not be you. Dark chocolate is high in antioxidants, but only the really dark stuff, and even then, the high saturated fat content and added sugars are certainly not healthy. Likewise, red wine is only comparatively good for you in the context of alcohol. It definitely has more going for it than beer, but your still probably better off not drinking any alcohol at all.

News stories are constantly telling us about some new ground-breaking study. Apparently, marijuana is a cure all for every disease known to man. Yet doctors don’t seem to be recommending it very often. Some will tell you it is all part of the big pharma conspiracy. But more than likely, its because those studies don’t mean anything when you compare them to the weight of our current medical knowledge. As more data is generated that may shift, but for now, do you want to try to control your seizures with marijuana because it worked for this one kid in Canada, or do you maybe want to try one of these other drugs first; that we have been using for years, that we know have worked for thousands of people, that have established dosing schedules to reduce the time to therapeutic concentrations, drugs whose short term and long term side effects and drug interactions have been extensively studied. If those don’t seem to work, by all means, try marijuana, but don’t expect it to be any reputable doctors ‘go to’ anytime soon.

-AMS