23. If the random variable X has the mean u and the stan- dard deviation o,...
Recall from class that the standard normal random variable, Z, with mean of 0 and stan- dard deviation of 1, is the continuous random variable whose probability is determined by the distribution: a. Show that f(-2)-f(2) for all z. Thus, the PDF f(2) is symmetric about the y-axis. b. Use part a to show that the median of the standard normal random variable is also 0 c. Compute the mode of the standard normal random variable. Is is the same...
6.33 Let x be a continuous random variable that is normally distributed with a mean of 25 and a standard deviation of 6. Find the probability that x assumes a value a. between 28 and 34 b. between 20 and 35 6.34 Let x be a continuous random variable that has a normal distribution with a mean of 30 and a stan- dard deviation of 2. Find the probability that x assumes a value a. between 29 and 35 b....
where p denote the population mean of the original random variable 5.7 Problems . Assume X is a normally distributed random variable with mean u and stan- dard deviation σ. A sample of size n-5 from this distribution is given as 1. Assume we are interested in the properties of the mean of the sam- pling distribution of the sample mean. Describe why this quantity is a 2. State an estimator for the parameter given in question 1. Use this...
If random variable X has normal distribution with mean u=50 and the standard deviation q=2 , then the value of z-score corresponding to the value X =60 is : - 10 - 5 - 50 - 0
Suppose x is a normal random variable with mean u and standard deviation o. If z is the standardized normal random variable of x, which of the following statements is false? (1) When r = y, the value of z=0. (2) When z is less than the mean y, the value of z is negative. (3) When r is greater than the mean y, the value of z is positive. (4) It is always the case that z <I.
Suppose density function positively valued continuous random variable X has the probability a fx(x)kexp 20 fixed 0> 0 for 0 o0, some k > 0 and for (a) Find k such that f(x) satisfies the conditions for a probability density function (4 marks) (b) Derive expressions for E[X] and Var[X (c) Express the cumulative distribution function Fx(r) in terms of P(), the stan dard Normal cumulative distribution function (8 marks) (8 marks) (al) Derive the probability density function of Y...
3. (5 marks) Let U be a random variable which has the continuous uniform distribution on the interval I-1, 1]. Recall that this means the density function fu satisfies for(z-a: a.crwise. 1 u(z), -1ss1, a) Find thc cxpccted valuc and the variancc of U. We now consider estimators for the expected value of U which use a sample of size 2 Let Xi and X2 be independent random variables with the same distribution as U. Let X = (X1 +...
4. Standard deviation and risk. The standard deviation o(X) of a random variable is the square root of the variance that is o(X) = Var(X). It characterizes the "spread" of the random variable X. If a random variable X has expected value p and standard deviation o, then X takes values which are on average at distance o from u. Imagine you have the choice to invest in two stock funds: an American fund with a rate return X and...
Random variable X has mean Ux=24 and standard deviation σx =6. Randon variable Y has mean Uy =14 and standard deviation σY = 4. A new random variable Z was formed, where Z=X+Y. What can we conclude about X, Y, and Z with certainty? That is, which one is true?