Suppose that T (≥ 0) is a continuous random variable. Let its
pdf, cdf, survival function, hazard rate function, and cumulative
hazard rate function be f(t), F(t), s(t), h(t), and H(t),
respectively. Note that H(t) is defined by R t 0 h(u)du.
a. Denote s(t), h(t), and H(t) as a function of f(t).
b. Denote f(t), h(t), and H(t) as a function of s(t).
c. Denote f(t), s(t), and H(t) as a function of h(t).
d. Denote f(t) and s(t)...
Let ?1, ?2,…. . , ?? (n random variables iid) as a
variable whose pdf is continuous and uniform over the interval [? -
1; ? + 3].
(1) Determine the estimator of the moments method.
(2) Is this estimator unbiased? What is its variance?
(3) Find the maximum likelihood estimator (VME) for this
setting. Is it unique?
Let X1,…, Xn be a sample of iid random variables with pdf f (x;
?1, ?2) = ?1 e^(−?1(x−?2)) with S = [?2, ∞) and Θ = ℝ+ × ℝ.
Determine
a) L(?1, ?2).
b) the MLE of ?⃗ = (?1, ?2).
c) E(? ̂ 2).
Let X1,…, Xn be a sample of iid Exp(?1, ?2) random variables
with common pdf f (x; ?1, ?2) = 1/ ?1 e^ −( x−?2)/ ?1 for x > ?2
and Θ = ℝ × ℝ+. a) Show that S = (X(1), ∑n i=1 Xi ) is jointly
sufficient for (?1, ?2).
b) Determine the pdf of X(1).
c) Determine E[X(1)].
d) Determine E[X^2 (1) ].
e) Determine Var[X(1)].
f ) Is X(1) an MSE-consistent estimator of ?2?
g) Given...
3. [5+5+1=11 pts]
a. Draw a frequency histogram for “Temp” variable from
“airquality” data. Use breaks=seq(55,
100, 5) in your hist() function. Show frequency on top of each
bar. Paste your graph below.
b. Draw a relative frequency histogram for “Temp” variable from
“airquality” data using the
same ‘breaks’ parameter. Add a density curve to it. Paste your
graph below.
c. What kind of distribution does the data exhibit? Right
skewed? Left skewed? Symmetric?
Let X1…X5 be iid random sample of size n=5 from a Uniform
distribution with parameters 0,theta. We test H0: theta=1 versus
H1: theta=2. Reject H0 when max(X1…X5)>b.
Find the value of b so that the size of the test is 0.10, then
find the power of this test.
Among the tests based on max(X1…Xn), find the most powerful
test with size exactly equal to 0.
Let X1, ..., Xn be iid with pdf f(x; θ) = (1/ x√ 2π)
e(-(logx- theta)^2) /2 Ix>0 for θ ∈ R.
(a) (15 points) Find the MLE of θ.
(b) (10 points) If we are testing H0 : θ = 0 vs Ha :
θ != 0. Provide a formula for the likelihood ratio test statistic
λ(X).
(c) (5 points) Denote the MLE as ˆθ. Show that λ(X) is can be
written as a decreasing function of | ˆθ|...
Let ?1. . . ?5 be identically independently distributed (iid)
variables sampled from a binomial distribution Bin(3,p).
a) Compute the likelihood function (LF).
b) Adopt the appropriate conjugate prior to the parameter p,
choosing hyperparameters optionally within the support of
distribution.
c) Using (a) and (b), find the posterior distribution of p.
d) Compute the minimum Bayesian risk estimator of p.
5. Find the sum of terms in given arithmetic sequence
1 + 3 + 5 + ... + 59
6. Find the sum of terms in given arithmetic sequence
2 + 5 + 8 + ... + 41
7.Given a geometric sequence
6 + 2 + 2/3 + ... is this sequence converging or diverging, if it
is converging find it's sum