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Let U be a Standard Uniform random variable. Show all the steps required to generate an Exponential random variable with the parameter lambda = 2.5; a Bernoulli random variable with the probability of success 0.77; a Binomial random variable with parameters n = 15 and p = 0.4; a discrete random variable with the distribution P(x), where P(0) = 0.2, P(2) = 0.4, P(7) = 0.3, P(11) = 0.1; a continuous random variable with the density f(x) = 3x2, 0 < x < 1; a continuous random variable with the density f(x) = 1.5x2, -1 < x < 1; a continuous random variable with the density f(x) = If a computer generates U and the result is U = 0.3972, compute the variables generated in (a)-(g).

User DivZero
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(a) To generate an exponential random variable with parameter lambda = 2.5 using a standard uniform random variable U, we can use the inverse transform method. The inverse of the cumulative distribution function (cdf) of an exponential distribution is given by:

F^(-1)(U) = -ln(1 - U) / lambda

Therefore, to generate an exponential random variable X with parameter lambda = 2.5, we can compute:

X = -ln(1 - U) / 2.5

If U = 0.3972, then:

X = -ln(1 - 0.3972) / 2.5 = 0.3146

(b) To generate a Bernoulli random variable with probability of success p = 0.77 using a standard uniform random variable U, we can use the following algorithm:

Generate U from a standard uniform distribution.

If U is less than p, set the Bernoulli random variable to 1 (success); otherwise, set it to 0 (failure).

If U = 0.3972 and p = 0.77, then:

Since U < p, the Bernoulli random variable is 1 (success).

(c) To generate a binomial random variable with parameters n = 15 and p = 0.4 using a standard uniform random variable U, we can use the following algorithm:

Generate U from a standard uniform distribution.

If U is less than p, count the trial as a success; otherwise, count it as a failure.

Repeat steps 1 and 2 for a total of n trials.

The binomial random variable is the number of successes.

If U = 0.3972 and n = 15, p = 0.4, then:

First trial: U > p, count as a failure.

Second trial: U < p, count as a success.

Third trial: U < p, count as a success.

Fourth trial: U > p, count as a failure.

Fifth trial: U > p, count as a failure.

Sixth trial: U > p, count as a failure.

Seventh trial: U > p, count as a failure.

Eighth trial: U < p, count as a success.

Ninth trial: U > p, count as a failure.

Tenth trial: U > p, count as a failure.

Eleventh trial: U > p, count as a failure.

Twelfth trial: U < p, count as a success.

Thirteenth trial: U > p, count as a failure.

Fourteenth trial: U > p, count as a failure.

Fifteenth trial: U < p, count as a success.

Therefore, the binomial random variable is 5 (number of successes).

(d) To generate a discrete random variable with distribution P(x), where P(0) = 0.2, P(2) = 0.4, P(7) = 0.3, P(11) = 0.1 using a standard uniform random variable U, we can use the following algorithm:

Generate U from a standard uniform distribution.

If U is less than P(0), set the random variable to 0; otherwise, check the next interval.

If U is less than P(0) + P(2), set the random variable to 2; otherwise, check the next interval.

If U is less than P(0) + P(2) + P(7), set the random variable to 7; otherwise, set it to 11.

If U = 0.3972, then:

First, we need to compute the cumulative probabilities for the distribution:

P(0) = 0.2

P(2) = 0.2 + 0.4 = 0.6

P(7) = 0.6 + 0.3 = 0.9

P(11) = 0.9 + 0.1 = 1.0

Since U is between 0.6 and 0.9, the random variable is 7.

(e) To generate a continuous random variable with the density f(x) = 3x^2, 0 < x < 1 using a standard uniform random variable U, we can use the inverse transform method. The cumulative distribution function of the continuous random variable is:

F(x) = ∫0x f(t) dt = x^3

Solving for x in terms of U, we get:

U = F(x) = x^3

x = U^(1/3)

If U = 0.3972, then:

x = 0.3972^(1/3) = 0.7269

Therefore, the continuous random variable is approximately 0.7269.

(f) To generate a continuous random variable with the density f(x) = 1.5x^2, -1 < x < 1 using a standard uniform random variable U, we can use the following algorithm:

Generate U from a standard uniform distribution.

If U is less than 0.5, set the random variable to
sqrt(U/1.5)- 1; otherwise, set it to 1 -
sqrt((1 - U)/1.5).

If U = 0.3972, then:

Since U < 0.5, the random variable is:


sqrt(0.3972/1.5) - 1 = -0.1024

(g) To generate a continuous random variable with the density f(x) = |x|, -1 < x < 1 using a standard uniform random variable U, we can use the following algorithm:

Generate U from a standard uniform distribution.

If U is less than 0.5, set the random variable to
sqrt(2U) - 1; otherwise, set it to
1 - sqrt(2(1 - U)).

If U = 0.3972, then:

Since U < 0.5, the random variable is:


sqrt(2(0.3972)) - 1 = 0.2399

User Wfh
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