9. Show that Y-Σ|-1 z? has a Chi-squared distribution with n degrees of freedom, where Z's...
Let Y~ xî (i.e. Y follows a chi-squared with 1 degree of freedom), let Xn = n-1/2 y - n1/2 (a) Show that Xn 4 X where X ~ N(0,2) (Hint: look up what is the mean and variance of a chi-squared distribution?) (b) n= 30. Find the exact P(Y > 43.8) using a chi-squared table. (c) Approximate P(Y > 43.8) for n = 30 using a normal approximation
3. If a random variable Y has a Chi-square distribution with 9 degrees of freedom. a) The mean of the distribution is b) The standard deviation of the distribution is c) The probability, p( y = 5) = d) The probability, P(Y>8 ) = e) the probability, p( y < 2) = _
PROBLEM 8: It is easy to show with mgf's that the sum of independent chi-squared random variables has a chi- squared distribution with degrees of freedom equal to the sum of the degrees of freedom associated with each of the random variables being summed. For example, if w (df -i) and all W's are independent, then Σ W,-X2 | df n(n+1 2 서 Now, suppose that X, N(i,i), and all X's are independent. Using your result in the previous problem...
10) Suppose that X follows a chi-square distribution with m degrees of freedom and S=X+Y. Given that S follows a chi-square distribution with m+n degrees of freedom, and X and Y are independent, show that y follows a chi-square distribution with n degrees of freedom.
imize File Preview ZOOM+ 5. (a) If T has a t-distribution with 9 degrees of freedom, Use Table IV in the book to find tsch that P(T < t) = 0.99 (b) If X has a Chi-Square distribution with 15 degrees of freedom, Use Table V in the 0.95 book to find z such that P(X <z) (c) Suppose a random sample of size 12 is taken from a Normal Population. If the population variance is 8, what is P(S214.3091)....
Let X be chi-squared with k = 5 degrees of freedom. (a) What is P[X > 1]? (This exact calculation requires some serious integration) (b) Find P[X > 1] with the normal approximation, i. e., approximate that probability assuming X ~ N(mu, sigma squared), where mu and sigma squared are the mean and variance of a Gamma(5/2, 1/2).
(a) Let X, have a chi-squared distribution with parameter V, and let X, be independent of X, and have a chi-squared distribution with parameter vz. Show that X, + X, has a chi-squared distribution with parameter v, + V Let Y = X1 + Xy. Identify the correct expression for Fly). Fyly) = (f1 +49 (0) BM={{1*(**) 2*3)**- _jei OFW - 1 -{{49)..:@) ib) dx1 FY) = -xq12 dx + -*2/20 1²ax 2 1/2 O Fy(y) :{"(****): 19). x 22...
21 (1 point) If Y X and every Xi is i.i.d with a chi-squared distribution with 14 degrees of freedom, find the MGF of Y М()- What is the distribution of Y? Select all that apply. There may be more than one correct answer. А. gатта(а - 147, 8 В. датта(а — 2, В — 294) с. датта(а — 1,8— 1/147) D. gamma(a 1, B 1/294) E. chi squared(df 294) F. еzрoпential(A — 204) G. exponential(A 147) H. chi squared(df...
Show that if Z is a standard normal random variable then Z2 has the Chi-square distribution with one degree of freedom.
proof for distribution of (n-1)S^2/sigma^2 is the chi square distribution with n-1 degrees of freedom. I don't understand the expansion of the square, specifically how certain terms disappeared and how a sqrt(n) appeared. Also towards the end, why does V have a degree of freedom of 1? x A detailed explanation of what happened from step 2 to step 3 would be very helpful! THEOREM B The distribution of (n − 1)S2/02 is the chi-square distribution with n – 1...