Chance News 101
Quotations
“It is easy to lie with statistics. It is hard to tell the truth without it.”
Submitted by Margaret Cibes
“Recently, I tried ‘treeing out’ (as the decision buffs put it) the choice [my patient] faced. …. When all the possibilities and consequences were penciled out, my decision tree looked more like a bush.”
Submitted by Margaret Cibes
From Significance, July 2014:
“Access to large databases does not reduce the need to understand why these particular samples are available.” [original emphasis]
“[In the early 1970s] I would be called to the bedside of a woman in labour; and instead of asking myself what was the best treatment for her I would find myself asking ‘Who is this woman’s consultant?’ Because all the consultants had their own favoured treatments and responses, whatever I suggested had to fit in which each of them. Nor was it evidence-based decision-making: it was eminence-based decision-making….” [emphasis added]
Note: British Clinician Archie Chalmers created the Cochrane Collaboration in early 1993 to provide to medical workers with easily accessible/readable summaries of all clinical trials on various treatments.
Submitted by Margaret Cibes
Forsooth
From Naked Statistics, by Charles Whelan, 2013
“Every fall, several Chicago newspapers and magazines publish a ranking of the ‘best’ high schools in the region. …. Several of the high schools consistently at the top of the rankings are selective enrollment schools …. One of the most important admissions criteria is standardized test scores. So let’s summarize: (1) these schools are being recognized as ‘excellent’ for having students with high test scores; (2) to get into such a school, one must have high test scores. This is the logical equivalent of giving an award to the basketball team for doing such an excellent job of producing tall students.”
“[T]he most commonly stolen car is not necessarily the kind of car that is most likely to be stolen. A high number of Honda Civics are reported stolen because there are a lot of them on the road; the chances that any individual Honda Civic is stolen … might be quite low. In contrast, even if 99 percent of all Ferraris are stolen, Ferrari would not make the ‘most commonly stolen’ list, because there are not that many of them to steal.”
“What became known as Meadow’s Law – the idea that one infant death is a tragedy, two are suspicious and three are murder – is based on the notion that if an event is rare, two or more instances of it in the same family are so improbable that they are unlikely to be the result of chance. Sir Roy [Meadow in 1993] told the jury in one of these cases that there was a one in 73m chance that two of the defendant's babies could have died naturally. He got this figure by squaring 8,500—the chance of a single cot death in a non-smoking middle-class family—as one would square six to get the chance of throwing a double six.” (footnote: “The Probability of Injustice”, Economist, January 22, 2004)
“John Ioannidis, a Greek doctor and epidemiologist, examined forty-nine studies published in three prominent medical journals [“Contradicted and Initially Stronger Effects in Highly Cited Clinical Research”, JAMA, July 13, 2005] …. Yet one-third of the research was subsequently refuted by later work. …. Dr. Ioannidis estimates that roughly half of the scientific papers published will eventually turn out to be wrong. His research was published in the Journal of the American Medical Association, one of the journals in which the articles he studied had appeared. This does create a certain mind-being irony. If Dr. Ioannidis’s research is correct, then there is a good chance that his research is wrong.” (emphasis added)
Submitted by Margaret Cibes