FORECASTING , THE COMPLETE ANSWERS TO THESE QUESTIONS WILL RECEIVE A THUMBS UP!

Weekly demand figures at Hot Pizza are as follows:

Estimate demand for the next 4 weeks using a 4-week moving average as well as simple exponential smoothing with α = 0.1. Evaluate the MAD, MAPE, MSE, bias, and TS in each case. Which of the two methods do you prefer? Why?

For the Hot Pizza data in Exercise 2, compare the performance of simple exponential smoothing with α = 0.1 and α = 0.9. What difference in forecasts do you observe? Which of the two smoothing constants do you prefer?

I NEED ALL THE ERRORS , FOR MOVING AVERAGE AND EXPONENTIAL SMOOTHING AND THE 4 WEEK FORECAST RESULTS , THANK YOU , THE ANSWERS TO THE QUESTIONS!!!!!

A clinical trial was conducted to test the effectiveness of a drug for treating insomnia in older subjects. Before​ treatment, 20 subjects had a mean wake time of 105.0 min. After​ treatment, the 20 subjects had a mean wake time of 98.5 min and a standard deviation of 21.52 min. Assume that the 20 sample values appear to be from a normally distributed population and construct a 95​% confidence interval estimate of the mean wake time for a population with drug treatments. What does the result suggest about the mean wake time of 105.0 min before the​ treatment? Does the drug appear to be​ effective? Construct the 95​% confidence interval estimate of the mean wake time for a population with the treatment.

Starting salaries of 110 college graduates who have taken a statistics course have a mean of $43,598. Suppose the distribution of this population is approximately normal and has a standard deviation of $8,635.
Using a 93% confidence level, find both of the following:

(a) The margin of error:  

(b) The confidence interval for the mean μ:

  <. ? <

Problem 4) Five coins are flipped. The first four coins will land on heads with probability 1/4. The fifth coin is a fair coin. Assume that the results of the flips are independent. Let X be the total number of heads that result.

(hint: Condition on the last flip).

a) Find P(X=2)

b) Determine E[X]

Do college students enjoy playing sports more than watching sports? A researcher randomly selected ten college students and asked them to rate playing sports and watching sports on a scale from 1 to 10 with 1 meaning they have no interest and 10 meaning they absolutely love it. The results of the study are shown below.

Assume a Normal distribution. What can be concluded at the the αα = 0.10 level of significance level of significance?

For this study, we should use Select an answerz-test for the difference between two population proportionst-test for the difference between two dependent population meansz-test for a population proportiont-test for the difference between two independent population meanst-test for a population mean

1. The null and alternative hypotheses would be:   
2.   

H0:H0:  Select an answerp1μdμ1 ?=>≠< Select an answer0μ2p2 (please enter a decimal)   

H1:H1:  Select an answerμdμ1p1 ?<=>≠ Select an answerp20μ2 (Please enter a decimal)

2. The test statistic ?zt = (please show your answer to 3 decimal places.)
3. The p-value = (Please show your answer to 4 decimal places.)
4. The p-value is ?≤> αα
5. Based on this, we should Select an answerfail to rejectrejectaccept the null hypothesis.
6. Thus, the final conclusion is that ...
   • The results are statistically insignificant at αα = 0.10, so there is insufficient evidence to conclude that the population mean rating for playing sports is greater than the population mean rating for watching sports.
   • The results are statistically insignificant at αα = 0.10, so there is statistically significant evidence to conclude that the population mean rating for playing sports is equal to the population mean rating for watching sports.
   • The results are statistically significant at αα = 0.10, so there is sufficient evidence to conclude that the ten students that were surveyed rated playing sports higher than watching sports on average.
   • The results are statistically significant at αα = 0.10, so there is sufficient evidence to conclude that the population mean rating for playing sports is greater than the population mean rating for watching sports.

Your friend’s professor gives out reasonably hard exams 70% of the time, and ridicu- lously hard exams 30% of the time. On hard exams, each student’s score on the exam is a normally distributed random variable with μH = 70 and σH = 10. On ridiculously hard exams, each student’s score on the exam is a normally distributed random variable with μR = 50 and σR = 15. Suppose you have four friends in the class, not just one. Let A be the average score of your four friends: A= (F1 +F2 +F3 +F4)/ 4 Where F1 is your first friend’s score, and F2 is your second friend’s score. Find E[A] and V ar(A) if the exam is ridiculously hard. (e) Find E[A] and V ar(A) if the exam is reasonably hard. (f) Since A is the sum of normal random variables, it is itself a normal random variable. Find P (A > 65) if the exam is reasonably hard, and if it is ridiculously hard. (g) If A is greater than 65, what is the probability the exam was ridiculously hard?

The yield of Australia bank stocks has a normal distribution with s.d. 0.024. A random sample of 10 Australian bank stocks gave the mean yield 0.0538. For the entire Australia stock market, the mean dividend yield is 0.047. Does this indicate that the dividend yield of all Australia bank stock is higher than 0.047? Let alpha = .01, do a hypothesis test.

a. test statement: null/alternative

b. calculate test statistic.

c. Find the critical value and draw a graph to find the reject region. Then make your decision.

d. Find the p value and draw a graph to mark the p value. Then make your decision.

e. Give your conclusion in a way that non-staticians can understand.

Let X₁,X₂,...X_n be a random sample of size n form a uniform distribution on the interval [θ₁,θ₂]. Let Y = min (X₁,X₂,...,X_n).

(a) Find the density function for Y. (Hint: find the cdf and then differentiate.)

(b) Compute the expectation of Y.

(c) Suppose θ₁= 0. Use part (b) to give an unbiased estimator for θ₂.

A company announced a "1000 Chips Trial" claiming that every 18 ounce bag of its cookies contained at least 1000 chocolate chips. Students purchased random bags from cookies from different stores and counted the number of chips in each bag. Some of the data is shown below.

1042 1132 1134 1255 1278 1233 1265 1339 1311 1450

Q1--Create a 95% confidence interval for the average number of chips. (SHOW EVERY STEP, I am completely lost on how to do this).

Q2--What percentage of bags will have fewwer then 1000 chips. (SHOW EVERY STEP).

**Only answer G-J, I already did A-F**

2. Measuring the height of a California redwood tree is very difficult because these trees grow to heights over 300 feet. People familiar with these threes understand that the height of a California redwood tree is related to other characteristics of the tree, including the diameter of the tree at the breast height of a person (in inches), the thickness of the bark of the tree (in inches), the distance from the closest neighboring tree (in yards), and the number of the other trees neighboring within 10 yards from the tree. Using the data set (Redwood.xlsx), conduct a regression analysis by answering the following questions.

(g) Determine the coefficient of determination, ? 2 , and interpret its meaning (f) At the level ? = 0.10, is there a significant relationship between the thickness and the pressure? Answer based on the t test in the p-value approach

(h) Determine the adjusted coefficient of determination, adjusted ? 2 , and interpret its meaning

(i) Evaluate the linearity assumption using the residual plot about the independent variable for diameter

(j) Evaluate the normality assumption using the normal probability plot

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Question: A researcher collected data from a random sample of 25 high school freshmen and found the mean of...

A researcher collected data from a random sample of 25 high school freshmen and found the mean of the sample to be 85.40 on the Test of Critical Thinking (TCT). She also calculated the standard deviation from the sample and discovered the value was 12.30. The average score on the Test of Critical Thinking for all high school seniors in a large school district is 90.00. The researcher wants to know if the mean TCT of the 25 high school freshmen in the random sample is different from the population’s (i.e., high school seniors) TCT mean.

e.What decision should be made about the null hypothesis? In other words, should you reject or retain the null hypothesis?
f. Construct a 95% confidence interval around the sample mean of 85.40. Does this confidence interval contain the population mean of 90.00?
g. Provide a brief conclusion regarding your findings. Use your powerpoint lecture slides for writing out the interpretation of your results.
[ME: What decision should be made about the null hypothesis? In other words, should you reject or retain the null hypothesis? (10p) e. f. Construct a 95% confidence interval around the sample mean of gaps. Does this confidence interval contain the population mean of 90.00? (Extra credit:10p) Provide a brief conclusion regarding your findings. Use your powerpoint lecture slides for writing out the interpretation of your results. (10p) g.]

9. The table below gives the number of hours five randomly selected students spent studying and their corresponding midterm exam grades. Using this data, consider the equation of the regression line, yˆ=b0+b1x, for predicting the midterm exam grade that a student will earn based on the number of hours spent studying. Keep in mind, the correlation coefficient may or may not be statistically significant for the data given. Remember, in practice, it would not be appropriate to use the regression line to make a prediction if the correlation coefficient is not statistically significant.

Hours Studying   1 2 3 4 5

Midterm Grades 62 66 76 77 81

Step 1 of 6: Find the estimated slope. Round your answer to three decimal places.

Step 2 of 6: Find the estimated y-intercept. Round your answer to three decimal places.

Step 3 of 6: Find the estimated value of y when x=2. Round your answer to three decimal places.

Step 4 of 6: Determine the value of the dependent variable yˆ at x=0.

Step 5 of 6: Find the error prediction when x=2. Round your answer to three decimal places.

Step 6 of 6: Find the value of the coefficient of determination. Round your answer to three decimal places.

The _______ is usually the hypothesis that the researcher wants to gather evidence against.

                null hypothesis

                alternative hypothesis

                one-tailed hypothesis

                two-tailed test of hypothesis

The _______ is usually the hypothesis for which the researcher wants to gather supporting evidence.

                one-tailed test of hypothesis

                null hypothesis

                two-tailed test of hypothesis

                alternative hypothesis

1. In a study of red/green color blindness, 700 men and 2050 women are randomly selected and tested. Among the men, 62 have red/green color blindness. Among the women, 4 have red/green color blindness. Test the claim that men have a higher rate of red/green color blindness.
The test statistic is  
The p-value is  
Is there sufficient evidence to support the claim that men have a higher rate of red/green color blindness than women using the 0.01% significance level?

A. No
B. Yes

2. Construct the 99% confidence interval for the difference between the color blindness rates of men and women.
<(p1−p2)<  

Which of the following is the correct interpretation for your answer in part 2?
A. We can be 99% confident that the difference between the rates of red/green color blindness for men and women lies in the interval
B. There is a 99% chance that that the difference between the rates of red/green color blindness for men and women lies in the interval
C. We can be 99% confident that that the difference between the rates of red/green color blindness for men and women in the sample lies in the interval
D. None of the above

1. In testing the null hypothesis that p = 0.3 against the alternative that p not equal 0.3, the probability of a Type II error is _____________ when p = 0.4 than when p = 0.6.

a. the same

b. smaller

c. larger

d. none of the above

2. During the pre-flight check, Pilot Jones discovers a minor problem - a warning light indicates that the fuel guage may be broken. If Jones decides to check the fuel level by hand, it will delay the flight by 45 minutes. If Jones decides to ignore the warning, the aircraft may run out of fuel before it gets to Gimli. In this situation, what would be:

i) the appropriate null hypothesis? and;
ii) a type I error?

Question 2 options: