# Re: [Vo]:Re: Regarding Rossi and NASA (+ some Piantelli news)

```Hi,

On 29-9-2011 8:27, Horace Heffner wrote:
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Looking at the other side of the coin, the probability of catastrophic failure, suppose there is a 0.1% chance per hour one of the E-cats can blow up spreading steam throughout the container. There is thus a 0.999 probability of success, i.e. no explosion for one E-cat, operating for one hour. The probability that all 52 E-cats perform successfully for a 24 hour test period is then 0.999^(52*24) = .287. That means there is a 71.3% chance of an explosion during a 24 hour test.

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Me thinks you are wrong. Your statistical probability calculation is based upon the fact that the chance of a single Ecat exploding is influenced by it's behaviour earlier, which of course is not true. Statistically each Ecat has it's own independent chance of explosion at any given moment which does not change over time. With your probability of 0,1% chance per hour this would result for the whole of 52 Ecats then in a chance of explosion at any given moment of 1 - (0.999^52) = .05 or 5%.
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Looking even a bit more closer again this would mean that if the chance of explosion is 0.1% per hour then the chance of explosion is 2,77e-7 per second at any given moment for a single Ecat, which would result for 52 Ecats into 1-((2,77e-7)^52) = 0,00001444434 or 0,00144% at any time.
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Kind regards,

MoB

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