Ver Chapter 5 Continuous Random Variables 1 Probability/Ch5
2 W say that X is a continuous random variable if there Continuous random variable
3 Probability/Ch5 As a result, Using the first fundamental theorem of calculus Example
4 Probability/Ch5 Expectation & Variance
5 Probability/Ch5
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7 proof
8 Probability/Ch5 Example Sol. Note that so, and A direct way is
9 Probability/Ch5 A random variable is (standard) uniformly distributed if its density function f ( x ) follows A random variable X ~unif( α, β ) has the following p.d.f. and c.d.f.
10 Probability/Ch5
11 Probability/Ch5 Need to prove Normal (Gauss) distribution
12 Probability/Ch5 Let We have It remains to show that
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14 Probability/Ch5 Taking differentiation,
15 Probability/Ch5 Therefore,
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20 Probability/Ch5 Note that therefore,
21 Probability/Ch5 That is or Recall Thus a exponentially distributed random variable is memoryless !!
22 Probability/Ch5 So, and, So, A variation of exponential distribution is the Laplace distribution, which has the density function. So,
23 Probability/Ch5 The meaning of the ‘hazard rate’ is suggested by the following: The hazard rate function uniquely determines the distribution function F. Why ?
24 Probability/Ch5 Note that Thus and
25 Probability/Ch5 However
26 Probability/Ch5 where Note that
27 Probability/Ch5 Suppose events are occurring randomly and in accordance with the three axioms for deriving Poisson distribution in sec.4.7. As a result, Taking differentiation, This shows that Here i.i.d stands for independent and identically distributed
28 Probability/Ch5 Thus Since These can also be seen from the fact that
29 Probability/Ch5 Example Sol.thus
30 Probability/Ch5 The Cauchy distribution is an example of a distribution which has no mean, variance, or higher moments defined. However, Furthermore,
31 Probability/Ch5 where
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33 Probability/Ch5 The left hand side
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35 Probability/Ch5 The distribution of a function of a random variable So,
36 Probability/Ch5 So,Proof Example Sol.