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The Variance Inflationary Factor (VIF) measures the

The Variance Inflationary Factor (VIF) measures the A. correlation of the X variables with the Y variable B. contribution of each X variable with the Y variable after all other X variables are included in the model C. correlation of the X variables with each other. D. standard deviation of the slope

To show that population mean is equal to mean of sample mean.

Q5: A group of poker players are profile in this month's magazine. The table below lists their name and average winnings per tournament. Consider this to be a population. Player Average Winnings Seattle Slim $27000 KC Kate $33000 Minnesota Mel $45000 Gotham City Graced $35000 The Player $60000 a) find the mean and sta

Moment around a Constant

(See attached file for full problem description) A set of numbers x_i, i = 1,...n, has a sample mean X and a variance. I would be grateful for a proof that the second moment of the x_i around a constant c is (see attachment) .

How Many Test Runs for a Sample Size?

The manufacturer of batteries used in small electric appliances wants to establish the average life of a battery. A random sample of 12 batteries yields a sample mean of 34.2 hours, and a sample standard deviation of 5.9 hours. Give a 95% confidence interval for the average life of a battery. Assume the underlying distribution

In a certain animal species...

In a certain animal species, the probability that a healthy adult female will have no offspring in a given year is .21, while the Probabilities of 1,2,3, or 4 offspring are respectively, .18, .29, .17, and .15. If a random variable X is used to represent the number of offspring, find its mean, variance, and standard deviation.

Calculating the f-stat to determine the difference between preservatives

The use of preservatives by food processors has become a controversial issue. Suppose two preservatives are extensively tested and determined safe for use in meats. A processor wants to compare the preservatives for their effects on retarding spoilage. Suppose 15 cuts of fresh meat are treated with preservative A and 15 are tr

F-stat calculation for upholstery business

An upholstery business is studying differences between two of its major outlet stores in the time it takes customers to receive furniture that was custom ordered. The following data shows a sample of delivery times for the most popular types of furniture: (see chart in attached file) Which of the following is the corr

Statistical Analysis of Psychotherapy Patients

You're conducting a study where participants are randomly assigned to two independent variables: number of sessions of psychotherapy (6 vs. 12) and use of antidepressants (using vs. not) on psychotherapy outcome. You would be pretty happy if you were checking assumptions for your ANOVA test and found this result. A. Levene


Overview River Beverages is a food and soft-drink company with worldwide operations. The company is organized into five regional divisions with each vice president reporting directly to the CEO, Cindy Wilkins. Each vice president has an R&D department, controller, and three divisions; carbonated drinks, juices and water, and f


An instructor asked 5 students how many hours they had studied for an exam. Here are the hours and the students grades Hours Grade 0 52 10 95 6 83 8 71 6 64 a. make a scatter diagram of the raw scores b. describe in words the general pattern of association c. figure the correlation coefficient d. explain

Random Variables and Statistical Analysis

X and Y are random variables. What are the marginal pdfs of (x+y) (where 0<x<1 and 0<y<1)? What is the expectation, covariance, correlation and and covariance coefficient? What are the joint and marginal pdfs and cdfs? (ii) Also,differently - if Fx|y(x|y) is constant over the 0 to 1. What is Fy|x(y|x)? (is there enough

Limiting Extreme-Value Distribution

I need some help with this statistics problem as well as some help understanding limiting distribution and the limiting extreme-value distribution: Consider a random sample of size n from a distribution with CDF (cumulative distribution function) F(x)=1-1/x if , and zero otherwise. a) Derive the CDF of the smallest order sta

Expected Return and Risk and Portfolios

1) What has been the expected return and risk for the S&P 500 during that time period (average annual return and standard deviation)? 2) How does the portfolio fair compare to the S&P 500? Explain. 3) Your client has $50,000 to invest and you plan to invest 60% in the security with the highest expected return. What would b

Finance Questions : Risk and Return, Rate of Return and Scenario Analysis

Risk and Return. True or false? Explain or qualify as necessary. a. The expected rate of return on an investment with a beta of 2 is twice as high as the expected rate of return of the market portfolio. b. The contribution of a stock to the risk of a diversified portfolio depends on the market risk

Statistic Problem

Hours Studied...........Test Grade ........0..............................52 .......10.............................95 ........6..............................83 ........8..............................71 ........6..............................64 Give the proportion of variance accounted for (R2).

This job focuses on between-groups variance.

If we do not observe a sufficiently large between-groups variance, then we have not observed __________ experimenter effects, an effect of the dependent variable, enough samples, or an effect of the independent variable I believe - enough samples - is the answer.

Random Variables : Expected Values

Let X be a random variable having expected value (mu) and variance (sigma)^2. Find the expected value and variance of: Y = (X - mu)/(sigma). (See attachment for full question)

Density Function : Calculate the Expected Values

1. Suppose U is a uniformly distributed random variable, so it has density fU(u) = 1 for 0&#61603;u&#61603;1, fU(u) otherwise. Calculate the expected values E[U] and E[U 2], and the variance of U. (Please see attachment.)

Measuring convergence

I need to measure the convergence of annual provincial data relative to the national. I have data for per capita annual income for two provinces and I have to compare them with the per capita national data and evaluate if the provincial data converge toward the national data. Can I do this with variance or standard deviation?

Error variance is high

Suppose the error variance in your study is high. Which of these statements is most likely to be true? a. Your power is high. b. The relationship between your independent variable and dependent variance is strong. c. Confounds interfered with measuring your dependent variable or manipulating your independent variable.

Linear Model / Parabola / Exponential, etc.

A. Which of the models would you use to determine the best choice of expiration date for the green beans? The cream pie? Why would you choose these? b. If, for practical reasons, you had to choose only one model to use to set the expiration dates, which would it be? (There is no health risk involved. It's a flavor quality thing