Given the samples X1 = {1, 0}, X2 = {0, 1}, X3 = {2, 1}, and X4 = {3, 3}.
Suppose that samples are randomly clustered into two clusters C1 = {X1, X3} and C2 = {X2, X4}.
a) Apply one iteration of K-means partitional clustering algorithm, and find a new distribution of samples in clusters.
1. Suppose that X1, X2, and X3 E(X1) = 0, E(X2) = 1, E(X3) = 1, Var(X1) = 1, Var(X2) = 2, Var(X3) = 3, Cov(X1, X2) = -1, Cov(X2, X3) = 1, where X1 and X3 are independent. a.) Find the covariance cov(X1 + X2, X1 - X3). b.) Define U = 2X1 - X2 + X3. Find the mean and variance of U.
The matrix is the reduced echelon matrix for a system with variables x1, x2, x3, and x4. Find the solution set of the system. (If the system has infinitely many solutions, express your answer in terms of k, where x1 = x1(k), x2 = x2(k), x3 = x3(k),and x4 = k. If the system is inconsistent, enter INCONSISTENT.) 1 0 0 0 | −5 0 1 0 0 | 3 0 0 1 0 | −5 0 0 0 1...
For the data x1 = -1, x2 = -3, x3 = -2, x4 = 1, x5 = 0, find ∑ (xi2).
Suppose that X1, X2, X3 and X4 are independent Poisson where E[X1] = lab E[X2] = 11 – a)b E[X3] = da(1 – b) E[X2] = X(1 — a)(1 – b) for some a and b between 0 and 1. Let S = X1 + X2+X3+X4, R= X1 + X2 and C = X1 + X3. (a) Find P(R = 10) (b) Find P(X1 = 6 S = 16 and R= 12). (c) Suppose we want to condition on the...
= = 3, Cov(X1, X2) = 2, Cov(X2, X3) = -2, Let Var(X1) = Var(X3) = 2, Var(X2) Cov(X1, X3) = -1. i) Suppose Y1 = X1 - X2. Find Var(Y1). ii) Suppose Y2 = X1 – 2X2 – X3. Find Var(Y2) and Cov(Yı, Y2). Assuming that (X1, X2, X3) are multivariate normal, with mean 0 and covariances as specified above, find the joint density function fxı,Y,(y1, y2). iii) Suppose Y3 = X1 + X2 + X3. Compute the covariance...
Suppose we need to construct a random variable X = {x1, x2, x3, x4} where x1 is sampled from N(0,1), x2 is sampled from U(0,1), x3 is sampled from Pois (0.5) and x4 from B (1000,0.5) where 1000 tosses of a fair coin are taken into an account (0 = tail, 1=head). What type of samples we would expect for X? Write 10 samples.
3. Let {X1, X2, X3, X4} be independent, identically distributed random variables with p.d.f. f(0) = 2. o if 0<x< 1 else Find EY] where Y = min{X1, X2, X3, X4}.
(1 point) Solve the system x +x2 x2 +x3 X1 +X4 X1 X2 X3 X4 +s
Matt’s utility is given by u(x1,x2)=min{x1,x2}+min{x3,x4}. Which of the following four bundles (A, B, C, and D) will he most prefer? Bundles are written (x1,x2,x3,x4). a. A = (2, 2, 2, 2) b. B = (6, 0, 0, 2) c. C = (4, 2, 1, 1) d .D = (6, 1, 3, 1)
Given the LPP: Max z=-2x1+x2-x3 St: x1+x2+x3<=6 -x1+2x2<=4 x1,x2<=0 What is the new optimal, if any, when the a) RHS is replaced by [3 4] b) Column a2 is changed from[1 2] to [2 5] c) Column a1 is changed from[1 -1] to [0 -1] d) First constraint is changed to x2-x3<=6 ? e) New activity x6>=0 having c6=1 and a6=[-1 2] is introduced ?