Rudy Giuliani, the Republican mayor of New York, on that fateful September 11, at an election meeting said: "I had prostate cancer 5 or 6 years ago and I thank God to be an American citizen because here the probability of survival at five years for this cancer is 82%, while in the UK, due to socialized medicine, this value is only 44%." We must clarify that in the US, PSA screening is widespread while in the UK it’s not so. According to Gerd Gigerenzer (I have extracted this case from his book "Risk Savvy"); Giuliani’s words conceal a big mistake, because in reality, although it seems a contradiction, mortality from prostate cancer in the two countries is practically the same. So how is it possible that the survival rates are so different? To explain it, Gigerenzer describes two biases that encourage the intentional error of the conservative politician:
