Let X, Y, Z be random variables. Prove or disprove the following statements. (That means, you need to either write down a formal proof, or give a counterexample.)

Statement 1. If X and Y are (unconditionally) independent, is it true that X and Y are conditionally independent given Z?

Statement 2. If X and Y are conditionally independent given Z, is it true that X and Y are (unconditionally) independent?

17. a researcher measures three variables, x, y, and z for each individual in a sample of n = 20. the pearson correlations for this sample are rxy = 0.6, rxz = 0.4, and ryz = 0.7. a. find the partial correlation between x and y, holding z constant. b. find the partial correlation between x and z, holding y constant. (hint: simply switch the labels for the variables y and z to correspond with the labels in the equation.) gravetter, frederick j. statistics for the behavioral sciences (p. 526). cengage learning. kindle edition.

East black horse $0.25 total budget is $555 it'll cost $115 for other supplies about how many flyers do you think we can buy

Find the missing dimension! need asap! tiny square is a =3025 in ²