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Re: Greater?
Posted:
Nov 25, 2013 10:10 AM


Le lundi 25 novembre 2013 14:37:17 UTC+1, Roland Franzius a écrit : > Am 25.11.2013 12:29, schrieb luttgma@gmail.com: > > > What is the probability that 14.5 +/ 0.8 is greater than 13.8 +/ 0.04 ? > > > > For two random production processes X, Y, normally and stochastic > > independently distributed with CDF NormalDistribution(m_k,s_k), the > > difference is normally distibuted with > > mean = difference of the means and variance = sum of variances: > > > > F(z)=Pr[XY < z ] > > = N( m1m2, sqrt(s1^2+s2^2) ) = N(0.7,sqrt(0.064+0.0016) ) > > > > So the answer may be probably > > > > CDF[NormalDistribution[0.7, Sqrt[0.8^2 + 0.04^2]]][0] > 0.191084 > > > > > >  > > > > Roland Franzius
14.5 +/ 0.8 billion years is the estimated age of the socalled "Methuselah star," cataloged as HD 140283. 13.8 +/ 0.04 billion years is the estimated age of the Universe.
According to your aanalysis, the probability that HD 140283 is older than the Universe is rather small.
Thank you very much,
Marcel



