Logestics Management Ch7 "Just-in-time and the agile supply chain" Based on this chapter answer the following.

1. Assess the reasons for using lean thinking (suitable examples), what are the benefits from Suppliers to end users?

Please assist with finding the mean, standard deviation and coefficient variation for the monthly profit of all the small, medium, large and very larges stores listed below.

Studies show that massage therapy has a variety of health benefits. A sample of 46 typical one-hour massage therapy sessions showed an average charge of $70. The population standard deviation for a one-hour session is $5.63. Estimate with 92% confidence the average charge of all one-hour massage therapy sessions. (Round to 2 decimal places.)

A European growth mutual fund specializes in stocks from the British Isles, continental Europe, and Scandinavia. The fund has over 200 stocks. Let x be a random variable that represents the monthly percentage return for this fund. Suppose x has mean μ = 1.3% and standard deviation σ = 1.1%.

(a) Let's consider the monthly return of the stocks in the fund to be a sample from the population of monthly returns of all European stocks. Is it reasonable to assume that x (the average monthly return on the 200stocks in the fund) has a distribution that is approximately normal? Explain.

---Select--- Yes No , x is a mean of a sample of n = 200 stocks. By the  ---Select--- central limit theorem law of large numbers theory of normality , the x distribution  ---Select--- is is not approximately normal.

(b) After 9 months, what is the probability that the average monthly percentage return x will be between 1% and 2%? (Round your answer to four decimal places.)


(c) After 18 months, what is the probability that the average monthly percentage return x will be between 1% and 2%? (Round your answer to four decimal places.)


(d) Compare your answers to parts (b) and (c). Did the probability increase as n (number of months) increased? Why would this happen?

No, the probability stayed the same.Yes, probability increases as the mean increases.     Yes, probability increases as the standard deviation decreases.Yes, probability increases as the standard deviation increases.

(e) If after 18 months the average monthly percentage return x is more than 2%, would that tend to shake your confidence in the statement that μ = 1.3%? If this happened, do you think the European stock market might be heating up? (Round your answer to four decimal places.)
P(x > 2%) =  

Explain.

This is very unlikely if μ = 1.3%. One would not suspect that the European stock market may be heating up.This is very likely if μ = 1.3%. One would not suspect that the European stock market may be heating up.     This is very likely if μ = 1.3%. One would suspect that the European stock market may be heating up.This is very unlikely if μ = 1.3%. One would suspect that the European stock market may be heating up.

Suppose bit errors in a digital data file occur independently with probability p = 0.25 · 10^−6 per bit.

X = number of bit errors in a 1 Mbyte data file (= 10^6 bytes) Calculate exactly or with suitable approximation

(a) X's standard and standard deviation;

b) the probability that at least three bit errors occur in the data file.

c) Suppose that instead of an unknown parameter. A test file of size 3.85 Mbytes is checked where 10 bit errors are found. Enter a numerical point estimate of p and enter its Standard deviation d [ˆp].

Question
(a) Consider a random sample of the following data: 254, 261, 250, 258, 253, 257.
Calculate the unbiased estimator of the population variance.

(b) Suppose the GPA of all students enrolled in a particular course can be modelled by a
certain distribution with a mean of 3.4 and variance 0.3. Compute the probability that the
mean GPA of a random sample of 40 students selected from this course will be:

(i) lower than 3.2
(ii) between 3.3 and 3.6

(c) Suppose you throw a die 600 times. Apply a suitable technique to compute the
approximate probability of obtaining between 90 and 110 fours.

During the next four quarters, Dorian Auto must meet (on time) the following demands for cars: 4000 in quarter 1; 2000 in quarter 2; 5000 in quarter 3; 1000 in quarter 4. At the beginning of quarter 1, there are 300 cars in stock. The company has the capacity to produce at the most 3000 cars per quarter. At the beginning of each quarter, the company can increase (but not decrease) its production capacity. It costs $100 to increase production capacity by one unit. For example, it would cost $10,000 to increase production capacity from 3000 cars per quarter to 3100 cars per quarter. It also costs $40 per quarter to maintain each unit of production capacity (whether it is used or not). The variable cost of producing a car is $2000. A holding cost of $150 per car is assessed for each quarter’s ending inventory. It is required that at the end of quarter 4, plant capacity must be at least 4000 cars.       

(1) Determine how to minimise the total cost incurred during the next four quarters.

There is a concern that due to rising material and labour costs, the variable cost in the fourth quarter may increase by 10%.

(2) Should you change your production plan if you believe this increase will occur?

(3) What would you do if you believed that there would be a 20% increase in variable costs in the fourth quarter?

Use both MATLAB Optimisation Toolbox and Excel Solver to solve the problems

A metropolitan transportation authority has set a bus mechanical reliability goal of 3,800 bus miles. Bus mechanical reliability is measured specifically as the number of bus miles between mechanical road calls. Suppose a sample of 100 buses resulted in a sample mean of 3,875 bus miles and a sample standard deviation of 275 bus miles.

population of bus miles is more than 3,800 (use a 0.01 level of significance)

(a) find the critical value(s) for the test statistic is(are) _

(b) is there sufficient evidence to reject the null hypothesis using a=0.01

(c) Determine the p-value and interpret its meaning

what is confounding and how researchers minimize it?

A sample of 40 companies listed on the stock exchange has an average amount of total assets equal to 431,000,000, with a standard deviation of 120,000,000. At level of confidence α=0.05, test the hypothesis that the average for all companies listed on the exchange is 600,000,000 or more.

Studies show that massage therapy has a variety of health benefits and it is not too expensive. A sample of 11 typical one-hour massage therapy sessions showed an average charge of $58. The population standard deviation for a one-hour session is σ = $5.1

a. What assumptions about the population should we be willing to make if a margin of error is desired?

- (The population has uniform distribution / The population is at least approximately normal is required / The population has exponentional distribution / No assumptions should be made)

b. Using 90% confidence, what is the margin of error (to 2 decimals)?

c. Using 95% confidence, what is the margin of error (to 2 decimals)?

MAT 152 Lab 4   

Show your work, where appropriate. Remember that you do not have to show any work for what you enter into your graphing calculator.

CITY is the city fuel consumption in miles per gallon and HWY is the highway fuel consumption in miles per gallon.

For parts A – C, find each of them. (There is no work required since your graphing calculator gives you these values.)                  Round each number to 3 decimal places.  

1. the linear regression equation:

2.    the correlation coefficient, r:

3. the coefficient of determination, r2:

4. Interpret r by explaining this value (from #2 above) in a COMPLETE sentence.
   

There is a _______________ _______________ linear correlation between city and

Choose strong or weak.    Choose positive or negative.

highway fuel consumption.

5. Interpret r2 by explaining this value (from #3 above) in a COMPLETE sentence by filling in the blanks:

_________ % of the variation in _______________ mileage can be explained by the

                Change r2 to a %.                                  Choose city or highway.

                regression equation.

            _________% of the variation is unexplained.

6. Determine if there is a significant linear relationship between city and highway fuel consumption at α=0.05 by completing the hypothesis test steps below.                                                                                                                                                 (Use LinRegTTest.)   

1. H₀:

H_a:

2. Calculate the test statistic: t = ___________                  Round to 3 decimal places.

3. Calculate the p-value: ____________                              Round to 4 decimal places.

4. Select the correct decision: Reject H₀                 or         Fail to Reject H₀

5. Conclusion: (Explain in terms of if there is a significant linear relationship or not).

I want examples on Sign test (one for small sample and one for large sample) and paired-sample sign test (one for small sample and one for large sample)

Consider a poor couple making decisions about the number of children. Suppose that in this society, there is no old age insurance, and parents must rely on their children for support.

Parents would like to receive old age support with a probability of at least q. Denote the number of children by n. Let p be the probability that a child (male or female) looks after the parents in old age.

a) What is the probability that a child does not look after the parents in old age?

b) What is the probability that out of n children at least one child looks after the parents in old age? Assume each child’s decision is independent of all others.

c) Find an expression that gives the optimal rule for the parents for deciding the number of children, given that they want the probability of being looked after to be at least q.

d) Let q=15/16 and p=1/2.What is the number of children that this couple will choose to have?

A simple random sample of 30 households was selected from a particular neighborhood. The number of cars for each household is shown below. Construct the 98% confidence interval estimate of the population mean.

2 0 1 2 3 2 1 0 1 4

1 3 2 0 1 1 2 3 1 2

1 0 0 5 0 2 2 1 0 2

A) 1.0 cars < μ < 2.0 cars

B) 0.9 cars < μ < 2.1 cars

C) 1.3 cars < μ < 1.7 cars

D) 1.5 cars < μ < 2.0 cars