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# Variance

### PERT Network Construction

Determine Earliest Start time (ES), Earliest Finish time (EF), Latest Start time (LS), Latest finish time(LF), and slack time for each activity Solve for: A) Construct a network for this problem B) Determine expected time and variance for each activity C) Determine Earliest Start time (ES), Earliest Finish time (EF), Lates

### Preparing a Flexiable Budget Performance Report

Please see attached file. Canyonland Boat Charter Services rents live aboard houseboats for cruising on the lake that traverses most of the Glen Canyon National recreation area in Southern Utah. The company bases its overhead cost budgets on the following data: Variable overhead costs: Cleaning \$72.50 per charter Maint

### Comprehensive Standard Cost Variances

Please see attached file. "It certainly is nice to see that small variance on the income statement after all the trouble we've had lately in controlling manufacturing costs," said Linda White, vice president of Molina Company. "The \$12,250 overall manufacturing variance reported last period is well below 3% limit we have set

### T-statistics Questions

A researcher conducts an independent measures research study and obtains t = 2.070 and df = 28. a. How many participated in this study? b. Using a two-tailed test with .05, is there a difference between the two treatment conditions? c. Compute r2 to measure the percentage of variance accounted for by the treatment ef

Order Up, Inc., provides order fulfillment for dot.com merchants. The company maintains warehouses that stock items carried by its dot.com clients. When a client receives an order from a customer, the order is forwarded to Order Up, which pulls the item from storage, packs it, and ships it to the customer. The company uses a pre

### The Solution to Degrees of Freedom

The number of degrees of freedom associated with the t test, when the data are gathered from a matched pairs experiment with 13 pairs, is .... For a set of data, the total variation or sum of squares for y is SST =180, and the error sum of squares SSE =54. What proportion of the variation in y is explained by the regression

### Working with Discrete Distributions

Let X1 and X2 have the joint pmf fiven by the following (X1,X2) f(X1,X2) (1,1) 3/8 (2,1) 1/8 (1,2) 1/8 (2,2) 3/8 Find: a.the marginal pmfs, f1(x1) and f2(x2) b. the means, m1 and m2 (mu) c. the variances, (sigma 1)^2 and (sigma2)^2 d. the covariance, sigma(sub 12) e. the correlation coeffiec

### Statistics discrete distributions and their properties.

Let four random variables X1, X2, X3, X4 have common mean m1=m2=m3=m4= 5 and common variance (sigma 1)^2= (sigma 2)^2= (sigma 3)^2= (sigma4)^2= 6 and common correlation coefficient p(sub ij)= .1, i does not equal j. Determine the mean and the variance of Y=X1 +X2 + X3 + X4

### Expectation and Variance of Industrial Operations

Please provide a solution for the following problem: For the daily output of an industrial operation, let Y1 denote the amount of sales and Y2, the costs, in thousands of dollars. Assume that the density functions for Y1 and Y2 are given by (see attachment). The daily profit is given by U =Y1 - Y2. a. Find E(U). b. Ass

### Mean and Variance in Glass Bottles

Approximately 10% of the glass bottles coming off a production line have serious flaws in the glass. If two bottles are randomly selected, find the mean and variance of the number of bottles that have serious flaws.

### Percentage of Variance and Regression Analysis

A professor obtains SAT scores and freshman grade point averages (GPAs) for a group of n=15 college students. The SAT scores have a mean of M=580 with SS=22,400 and the GPAs have a mean of 3.10 with SS=1.26 and SP=84. What percentage of the variance in GPAs is accounted for by the regression equation? (Compute the correlation

### Calculations of Variance of the Population

The weights of a random sample of cereal boxes that are supposed to weigh one pound are listed here. Estimate the variance of the entire population of cereal box weights with 90% confidence. 1.05 1.03 .98 1.00 .99 .97 1.01 .96

### Wide Sense Stationary and Ergodic Processes

A random process has sample functions of the form X(t)=A where A is a Rayleigh distributed random variable with mean of 4. A) Is this process wide sense stationary? If so, why? B) Is this process ergodic? If so, why?

### Deterministic Random Process: The Mean Value and Variance

Sample functions from a deterministic random process are described by X(t)= At + B t>=0 = 0 t<0 where A is a Gaussian random variable with zero mean and a variance of 9 and B is a random variable that is uniformly distributed between 0 and 6. A and B are statistically independent. A) Find the mean value

### Variable Cost Variance

How do you do this problem (see attached)?

### Criminal Procedure Variation

Please assist so that I can complete this assignment: ?&#61472;Research your state's criminal procedures and choose a crime to review. (My state is Pennsylvania). ?&#61472;Locate a state that has a variance in their procedures for the same crime. (Any State). Describe the similarities and differences between the proced

### What is the relationship between the variance and the standard deviation? ...

What is the relationship between the variance and the standard deviation? Why is the unbiased estimator of variance used?

### Business Statistics Finite Random Numbers

Homework #8 Question 1 refers to the finite random variable X, whose p.m.f. is given below. x 0 1 2 4 8 fX(x) 0.1 0.2 0.4 0.2 0.1 Compute the mean, &#61549;X, variance, V(X), and standard deviation, , of X. Questions 6 and 7 refer to the random variable X which gives the number of customers who visit my busi

### Elementary Statistics and Frequency Distribution

Find P25 for the following data: 2 6 3 4 2 1 2 0 1 3 6 3 You are given the following frequency distribution for the number of errors 10 students made in a test Errors Frequency 0-2 14 3-5 13 6-8 11 9-11 8 12-14 9 Find: a. mean b. variance c. standard deviation.

### Finding the 90% Confidence Interval

What is the 90% confidence interval for the variance of the exam scores for 28 algebra students, if the standard deviation on their last exam was 12.7? a. 122.8 < o < 316.5 b. 108.6 < o < 269.6 c. 10.4 < o < 16.4 d. 123.7 < o < 312.7

### Compute Mean and Variance

The Excel file provides data on the annual percent changes in the Dow Jones Industrial average, Consumer Price Index, Standard & Poor's 500, and average yield for one-year Treasury bills from 1960 through 1999. Compute the mean and variance for the percent changes in the DJIA and S&P 500 indexes.

### Expected Values - Barron Big Money Poll

The Barron Big Money Poll asked 131 investment managers across the United States about their short-term investment outlook (Barrons, October 28, 2002). Their responses showed 4% were very bullish, 39% were bullish, 29% were neutral, 21% were bearish, and 7% were very bearish. Let x be the random variable reflecting the level of

### Statistics

1. The following sample observations were randomly selected. Determine the coefficient of correlation and the coefficient of determination. Interpret. 2. The following sample observations were randomly selected. Determine the coefficient of correlation and the coefficient of determination. Interpret the association betwee

### Expectation and variance of a random Variable

Let X be a random variable with the following probability distribution Value x of X P(X=x) 0 0.30 10 0.35 20 0.05 30 0.15 40 0.15 Find the

### Stock Returns

A stock's return has the following distribution: Demand for the Company's Products Probability of This Demand Occurring Rate of Return if This Demand Occurs Weak 0.05 (40%) Below average 0.25 (4%) Average 0.40 20% Above average 0.25 35% Strong 0.05 55% 1.00 What is the stock's expected return? What is the stoc

### Forecasting, Seasonal Variations, Cost Control

1. The healthcare environment would be advised to use the MAD, MSE, and the MAPE as measures of forecasting accuracy. Describe how these techniques could aid managers in the projections of cost and assist in inventory control. 2. Summarize the factors involved with seasonal variations. Provide examples. 3. An essentia

### Stock's expected return, standard deviation, and coefficient of variation.

A Stock's return has the following distribution: Demand for the company's products: Probability of this rate of return if it demand occurring occurs Weak 0.1

### Crede Manufacturing: Price and quantity variances

Crede Manufacturing uses standard cost accounting. In 2005, 33000 units were produced. Each unit took several pounds of direct materials and 1 1/3 standard hours of direct labor at a standart hourly rate of \$12.00. Normal capacity was 42,000 direct labor hours. During the year 132,000 pounds of raw materials were purchased a

### Finance : Debt and Asset Beta, Debt-to-Equity Ratio, Balance Sheets and Market Value

12.8 The following table lists possible rates of return on Compton Technology's stock and debt and on the market portfolio. The probability of each state is also listed. State Probability Return on Stock (%) Return on Debt (%) Return on the Market (%) 1 0.1 3% 8% 5% 2 0.3 8 8 10 3 0.4 20 10 15 4 0.2 15 10 20 1. What i

### Cramer Rao Lower Bound

Given a random sample of size n from a normal distribution N(lambda,lambda) - ie mean =lambda and variance =lambda - If X.bar is used to estimate lambda, show that X.bar exceeds the Cramer - Rao lower bound