- Premium Academic Help From Professionals
- +1 810 395 5448
- support@grademaster-pro.com

STA 261 Online – Which Inference Procedure Discussion #4

This assignment is meant to give you a chance to apply what you learned about our different inference procedures learned in Module 5 and to talk with your peers about anything you feel you are struggling to understand about determining when to use each method and what to use in StatCrunch.

You will work together to solve these problems via the discussion forum. Together you will discuss one of the difficulties experienced by students on exam 2, knowing when to use which inference procedure.

As you work through this assignment, keep the following things in mind:

- You are all responsible for understanding the solutions to ALL problems. You may see problems like these on your next exam, and some of these problems are similar to problems in your next homework assignment, so it’s important that you each understand how to solve them.
- Have your group choose a group leader – someone who will post the final summary (the last post in the group’s discussion forum). The group leader will get an extra point for compiling the summary.
- If you happen to have difficulties solving the problems, please let your group members know. Don’t be afraid to ask the group for help or to admit that you are struggling. This is challenging material, so if you are not getting it right away, that is okay! Use this time with your group to get some help.

**As an extra incentive for this discussion, the group will receive an extra half point for each problem that is CORRECTLY solved in the final summary.** Thus, you could each receive an extra 4 points for this discussion forum assignment.

**Each individual student must contribute at least five total posts (three initial posts and two responses to classmates’ posts) in order to receive full credit.** Each group member is welcome to include more than five posts. It is your responsibility to work with your group members to divide up the problems to ensure that each of the eight problems are addressed throughout the discussion. You must post your initial posts before you can see your classmates’ posts. **All posts must be written in the discussion post, NO LINKS TO OUTSIDE DOCUMENTS!**

**Initial Post Requirements**– Provide the following for**one**of the questions listed at the end of this document. An initial post should only address**one**question, so you must address a total of three questions with your__three__initial posts. More than one group member will be addressing the same problem with an initial post.- The question text
- What are the observational units?
- What is/are the parameter(s) of interest?
- What is the null hypothesis and alternative hypothesis?
- Which hypothesis test you believe you should use and why.

**Response Post Requirements**– Discuss whether or not you agree with your classmate’s solution. Simple responses such as “I agree” or “I disagree” are not acceptable.- If you agree with your classmate, discuss if there is anything missing from the solution.
- If you disagree with your classmate, discuss why you disagree. Be sure to include how you would solve the problem differently.
- Are the assumptions met?
- What is the test statistic, degree of freedom (if required) and p-value.
- What is the conclusion.?

Please note that you will not receive full credit for the discussion part of this project if all of your discussion posts are completed on the day in which the discussion closes. **Additionally, you will not receive credit for any posts completed outside of your group’s discussion page on Canvas.**

**25 points**– The student contributed at least five total posts (three initial posts and two responses to classmates’ posts) throughout the discussion period. The posts include original ideas and it is evident that the student put time and effort into crafting thoughtful responses.*The student’s posts were not all completed on the day in which the discussion closes.***23 points**– The student contributed at least five total posts (three initial posts and two responses to classmates’ posts). The posts include original ideas and it is evident that the student put time and effort into crafting thoughtful responses.*The student completed all posts on a single day OR on the day in which the discussion closes.***19 points**– The student contributed at least five total posts (three initial posts and two responses to classmates’ posts), but might not have included the necessary depth or detail in one or more of the posts.**13 points**– The student contributed three or four total posts. The posts include original ideas and it is evident that the student put time and effort into crafting thoughtful responses.**10 points**– The student contributed one or two total posts. The posts include original ideas and it is evident that the student put time and effort into crafting thoughtful responses. OR The student contributed three or four total posts, but might not have included the necessary depth or detail in one or more of the posts.**6 points**– The student contributed one or two total posts, but might not have included the necessary depth or detail in one or more of the posts.**0 points**– The student did not participate in the discussion.

__ __

__ __

__ __

__ __

__ __

__ __

__ __

__ __

__ __

__Inference Procedures to Choose from__

- One Sample Proportion Z-test
- Two Sample Proportion Z-test
- One Mean t-test
- Pooled t-test
- Non-Pooled t-test
- Paired t-test

__Please note: ____All datasets are in our StatCrunch Group entitled Which Inference? Datasets__

__Questions:__

- Your statistics professor is interested if the proportion of STA 261 students that plan on taking a class over the upcoming summer term is over 33%. A random sample of 33 261 students was taken. Of the 33, only 8 students planned on taking a course this upcoming summer course. Is there evidence to conclude that the population proportion of 261 students planning on taking a summer course is over 33%? Use a significance level of 0.10.
- Researchers at Novartis, a company that makes vaccines, are trying to create a new vaccine designed to prevent the flu. The company states that the vaccine is equally effective for men and women. To test this claim, they choose a simple random sample of 500 women and 600 men from a population of 500,000 volunteers.

At the end of the study, 42% of the women and 53% of the men caught the flu. Based on these findings, can we reject the company’s claim that the vaccine is equally effective in preventing the flu for men and women? Use significance level of 0.05.

- The NOAA National Climatic Data Center of the United States provides data on the average annual temperature for every state in the United States. The average annual temperatures are based on data collected by weather stations throughout each state during the years 1971 to 2000. Is there strong evidence that the mean average annual temperature in the United States is greater than 50 degrees Fahrenheit? Explain. Use a significance level of 5%.
- As gas prices continue to rise, more customers are beginning to take into account miles per gallon (a measure of the average distance traveled per unit of energy consumed) when determining which type of car to purchase. Do cars made in Japan typically get more miles per gallon than cars made in the United States? A random sample of 79 cars made in Japan had a mean of 30.48 and a standard deviation of 6.11 miles per gallon. A random sample of 249 cars made in the United States produced a mean of 20.14 and a standard deviation of 6.41 miles per gallon. Use a significance level of 0.10.
- The U.S. Census Bureau reports that 26% of all U.S. businesses are owned by women. A Colorado consulting firm surveys a random sample of 410 businesses in the Denver area and finds that 115 of them have women owners. Should the firm conclude that its area is unusual? Test an appropriate hypothesis and state your conclusion. Use a significance level of 0.05.
- Do upright and canister vacuum cleaners cost the same amount of money, on average? Independent, random samples of upright and canister vacuums of various brands were obtained and their prices (in dollars) were recorded. The summary statistics are included in the table. (Data retrieved from HomeOwl.com) Create and interpret a 90% confidence interval for the difference between the average cost of upright and canister vacuum cleaners.
- Is the Freshman 15 real? A study was conducted on incoming freshmen at Mount Mercy College in Cedar Rapids, Iowa. The weights from a simple random sample of 67 freshmen students were recorded in both September (the beginning of the school year) and again in April (the end of the school year). The data was published in the Journal for American College Health and is shown in the Which Inference Procedure? data set in our StatCrunch group. Is there any evidence that the average weight for freshmen students at Mount Mercy College in April is greater than the average weight in September? Use a significance level of 10%.
- Observers in Texas watched children at play in eight communities. Of the 814 children seen biking, roller skating, or skateboarding; only 14% wore a helmet. Create and interpret a 95% confidence interval to estimate the proportion of children that wear helmets. Assume the children are representative of all children in those communities.

error: Content is protected !!

Open chat

You can contact our live agent via WhatsApp! Via our number +(323) 333-4455

Feel Free To Ask Questions, Clarifications, or Discounts, Available When Placing the Order.