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Statistics and ordering

A candy store sells 18 candy bars per day on average with a Standard dev. of 3 candy bars per day. The supply company has an average delivery time of two wks with a standard deviation of two days. The candy store is open for business six dys per wk forty eight weeks of the yr. When they order it costs the candy store ten dollars

Bioninomal Distribution

Ther are 8 balls in a sample 5 white and 3 black .x is the number of black balls in the sample. three white are selected. white are selected from sample.write the probability distribution and find of x . and find mean , variance and standard derivation.

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?


1)If the standard deviation is 1.71 what is the variance? 2)Using the probability distribution listed. What is the mean? x 0 1 2 3 P(x) 0.2 0.1 0.3 0.4

Criminal Procedure Variation

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

Business math homework problems

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, 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

Show that constants are normally distributed.

Let X1 and X2 denoted independent, normally distributed random variables, not necessarily the same mean or variance. Show that any constants "a" and "b", Y= aX1 + bX2 is normally distributed. Help: ===== I'm not sure if I can just prove it by showing what I have below. where, SX2 ---> INTEGRATION FROM X_2 SX1 ---> INTEG

Order Statistics and Variance

From Order Statistics. Please show each step of your solution. You can use technological device(e.g. excel, Maple, or Mathematica, etc) if you want, but please explain your work.

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

PMF, Variance and Skewness

From Mean, Variance, and Standard Deviation Please see the attached file for the fully formatted problem.

Uncertainty Exercises and Sums of Variances

Need just the answers. Basically, in the question where there is a question mark (?) should be replaced by the solution. Error of input quantities are assumed to be statistically independent Please see the attached file (with bilingual instruction).


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

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

Error Sum of Squares

If the total sum of squares in a one-way analysis of variance is 25 and the treatment sum of squares is 17, then the error sum of squares is?

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

MVB or UMVUE for Gamma

For the X~ Gamma (alpha, Lambda), Find the optimal estimators of n/lambda and n/lambda^2 Ether UMVUE or MVB may be used to find the estimator. See attached file for full problem description.

Pooled vs Unpooled Variance

Distinguish between unpooled variance and pooled variance. What are the assumptions of each? How do you determine which is appropriate?

Derive the quantization formula of a sine wave.

Derive the quantization formula based upon the variance of a sinewave and the variance of distortion due to quantization. This is the signal to distortion (SDR) ratio for a quantized sinewave. A is the amplitude of the quantized sinewave and Delta is the quantization interval of the analog to digital converter, and the quant

Statistics Questions

Should Statistics Be a Required Course in College? Yes No Republican 10 26 Democrat 15 17 1. Cell 1,1 (Yes, Republican) Expected Value = 2. Cell 2,2 (No, Democrat) Expected Value = (You must calculate E for the other two cells) 3. What is the result of this analysis? 4. What is

Relationship of a list of two variables

Suppose a small group of physicists and mathematicians, each an expert in his or her field... Relationship of a list of two variables. See attached file for full problem description.

Math - Interpreting Results of Statistics

The IRS is concerned with improving the accuracy of tax information given by its representatives over the telephone. Previous studies involved asking a set of 25 questions of a large number of IRS telephone representatives to determine the proportion of correct responses. Historically the average proportion of correct responses

Whole Number Variance

Use whole numbers 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 to make up a list of 6 numbers. Use as many of the numbers, as many times as you want. Show a list of six numbers with the largest variance, and a list of six numbers with the smallest variance.