Random variables
Random variables with zero correlation are not necessarily independent. Give a simple example.
Expert
Let X be a normally-distributed random variable with
Mean zero. Let Y = X^2. Obviously, X and Y are not independent: knowing X, gives the value of Y.
The covariance of X and Y is Cov(X,Y) = E(XY) - E(X)E(Y) = E(X^3) - 0*E(Y) = E(X^3) = 0,
because the distribution of X is symmetric around zero. correlation r(X,Y) = Cov(X,Y)/Sqrt[Var(X)Var(Y)] = 0, the random variables are not independent, but correlation is zero.
Explain sampling bias and describe how random sampling serves to avoid bias in the process of data collection.
The table below illustrates the relationship between two variable X and Y. A
what are the advantages and disadvantages of seasonal variation
Suppose that your utility, U, is a function only of wealth, Y, and that U(Y) is as drawn below. In this graph, note that U(Y) increases linearly between points a and b. Suppose further that you do not know whether or not you
Discuss the following statements and explain why they are true or false: a) Increasing the number of predictor variables will never decrease the R2 b) Multicollinearity affects the int
It doesn't rain often in Tucson. Yet, when it does, I want to be prepared. I have 2 umbrellas at home and 1 umbrella in my office. Before I leave my house, I check if it is raining. If it is, I take one of the umbrellas with me to work, where I would leave it. When I
You must use the pre-formatted cover sheet when you hand in the assignment. Out full detailed solutions. Sloppy work will naturally receive a lower score. 1. Suppose at each step, a particle moving on sites labelled by integer has three choices: move one site to the right with pro
1) A Discrete random variable can be described as Binomial distribution if is satisfies four conditions, Briefly discuss each of these conditions2) A student does not study for a multiple choice examination and decides to guess the correct answers, If the
what is the appropriate non-parametric counterpart for the independent sample t test?
18,76,764
1932656 Asked
3,689
Active Tutors
1448840
Questions Answered
Start Excelling in your courses, Ask an Expert and get answers for your homework and assignments!!