"Data 2 below (a sample from your production line) and Data 4 (sample test data, which you received from your competitor). Calculate the P-value when comparing the population variances of these two groups."

Please include excel calculations.

Data 2

Data 4

We are interested in estimating the proportion of graduates from Lancaster University who found a job within one year of completing their undergraduate degree. Suppose we conduct a survey and find out that 354 of the 400 randomly sampled graduates found jobs. The number of students graduating that year was over 4000.

1. (a) State the central limit theorem.

2. (b) Why is the central limit theorem useful?

3. (c) What is the population parameter of interest? What is the point estimate of this parameter?

4. (d) What are the assumptions for constructing a confidence interval based on these data? Are they met?

5. (e) Calculate a 95% confidence interval for the proportion of graduates who found a job within one year of completing their undergraduate degree. Interpret this within the context of the data.

6. (f) Without doing any calculations, describe what would happen to the confidence interval if we decided to use a higher confidence level, e.g., 99%.

7. (g) Without doing any calculations, describe what would happen to the confidence interval if we used a larger sample.

Two candidates are running for​ president: John Democrat and Joe Republican. A recent survey concluded that John Democrat had a probability of 0.44 to win the election.Two hundred people are interviewed at random about whom they would vote for. A random variable X is defined as the number of people who said they would vote for John Democrat. Find the expected value of the random variable

The daily selling price per 100 pounds of buffalo meat is normally distributed with a mean of 70 dollars, and the probability that the daily price is less than 85 dollars is 0.9332. Four days are chosen at random, what is the probability that at least one of the days has a price that exceeds 80 dollars?

1. Obtain 1337 values, at random, from a uniform distribution where the smallest possible value is 20 and the largest possible value is 40. Label the vector ex5. Also, consider ex5 the population. Report all R code

At a western hospital there was a total of 932 births in 20 consecutive weeks. Of these births, 216 occurred on weekends. Based on these data, are birth rates different on weekends and weekdays?

a) Name two statistical methods that could be used to test hypotheses. State the advantages and disadvantages of both.

DO NOT USE EXCEL SHOW STEPS EXPLAIN ALL PARTS

A group of 18 people from New York and a group of 15 people from Los Angeles passed the same quiz. The mean grade of group A is 78 points, with the standard deviation σ1=5, the mean grade of group B is 75 points, σ2=4.5. Use α=0.05. Assuming that the subjects are chosen randomly, the cities’ population are independent, and the points are normally distributed:

(a) Check if there is a significant difference between the mean grades of the groups. Find the P-value of this test.

(b) Explain how the test could be conducted with a confidence interval.

(c) What is the power of the test for the true difference in means of 2.5?

(d) Assume that sample sizes are equal. What group size should be considered to obtain β=0.1 if the true difference in means is 2.5?

1- A sample of 2 different calculators is randomly selected from a group containing 13 that are defective and 8 that have no defects. Assume that the sample is taken with replacement. What is the probability that at least one of the calculators is defective? Express your answer as a percentage rounded to the nearest hundredth.

2- Use the data in the following​ table, which lists​ drive-thru order accuracy at popular fast food chains. Assume that orders are randomly selected from those included in the table. ​

Drive-thru Restaurant  /  A  /  B  /  C  /  D
Order Accurate         / 27 / 35 / 21 / 19
Order Not Accurate     / 1 / 40 / 10 / 21

If one order is​ selected, find the probability of getting an order from Restaurant C given the order that is accurate. Express your answer as a percentage rounded to the nearest hundredth.

Complete this exercise using the Seven Steps to Hypothesis Testing.

A university president collects data showing the number of absences over the past academic year for a random sample of 6 professors in the College of Engineering. He does the same for a random sample of 9 professors in the College of Business and for a random sample of 8 professors in the College of Fine Arts. Assuming an alpha of .05, is there a significant difference in absences among colleges?

A sample of 30 recently sold single-family houses in a small city is selected. Develop a model to predict the selling price (in thousands of dollars), using the assessed value (in thousands of dollars) as well as time (in months since reassessment). The houses in the city had been reassessed at full value one year prior to the study. The results are stored in House1.xls.

a. State the multiple regression equation.

b. Interpret the meaning of the slopes in this equation.

c. Predict the selling price for a house that has an assessed value of $170,000 and was sold 12 months after reassessment.

d. Perform a residual analysis on your results and deter-mine whether the regression assumptions are valid.

e. Determine whether there is a significant relationship be-tween selling price and the two independent variables (assessed value and time period) at the 0.05 level of significance.

f. Determine the p-value in (e) and interpret its meaning.

g. Interpret the meaning of the coefficient of multiple determination in this problem.

h. Determine the adjusted

i. At the 0.05 level of significance, determine whether each independent variable makes a significant contribution to the regression model. Indicate the most appropriate regression model for this set of data.

j. Determine the p-values in (i) and interpret their meaning.

k. Construct a 95% confidence interval estimate of the population slope between selling price and assessed value.

EXCEL DATA BELOW:

This question was asked, and partially answered once before. However, I need step by step answers to for a clearer comprehension. Please provide answers for a through k

1.       Provide some examples of how you might use decision models in your personal life or in the context of current or prior work experience.

Quarter Enrollments in Business Statistics course at a major university are given in the EXCEL worksheet Enrollment:

1. Develop an additive model for trend and seasonality. Please clearly define your variables.

b. Use the additive model to forecast for the enrollments for Fall 2013, Winter 2014, and Spring 2014.

Please show step by step instructions using excel:

Costello Music Company has been selling electronic organs over the past 5 years. Sales were initially low but have grown over time. Ray Costello, the owner of the company, wants to predict the sales for the upcoming year using the number of sales that Costello Music Company has experienced. The sales totals are given in the following table.

a) Using the centered moving average approach (CMA) what are the seasonal indexes for the four quarters?

b) In which quarter does Costello Music Company experience their largest seasonal effect? Does this result seem reasonable? Explain your answer.

c) Using multiplicative decomposition predict the level of sales for each quarter next year. Report your results.

IQ is normally distributed with a mean of 100 and a standard deviation of 15. Suppose one individual is randomly chosen. Let X = IQ of an individual.

Part B

Find the probability that the person has an IQ greater than 110.

What is the probability? (Round your answer to four decimal places.)

Part C

The middle 60% of IQs fall between what two values?

State the two values. (Round your answers to the nearest whole number.)

What is the probability? (Round your answer to four decimal places.

1. The University is interested in determining if the number of people coming to work by pedal bicycle has changed from 2016 to 2017. Over the course of a week (Mon-Sun) they count the number of cyclists who enter campus at the North campus cycle path entrance between 8am-10am each day. The University have data from the same week in 2016. The counts for each day of the week for 2016 and 2017 are given in Table:

   	Mon	Tues	Wed	Thurs	Fri	Sat	Sun
   2016	243	175	255	187	241	53	32
   2017	254	242	250	263	235	51	35

   1. Describe one positive and one negative aspect of the University's sampling strategy
   2. Explain why a paired approach is appropriate for this test
   3. Write down appropriate null and alternative hypotheses for this test.
   4. Calculate the mean and variance of the differences di=xi-yi.
   5. What assumptions are required to conduct your hypothesis test from (c), does this data satisfy them?
   6. Using your answer to part (d), or otherwise, calculate a 90% confidence interval for the difference in the average number of cyclists.
   7. Using your answer to part (f), or otherwise, test your hypothesis from (c)  at the 10% level. You should clearly state the conclusion of your test.
   8. From Table 1 it looks like Tuesday and Thursday have the largest difference from one year to the next.  Why is it wrong to now testing the hypothesis  “2017 has more cyclists on Tuesdays and Thursdays than in 2016”?

Please explain part h) more details, thanks a lot.