Stat 201



Stat 201 – Project 3 – Spring 2020Due Friday, April 24, 2020(1 minute before midnight, submitted to Canvas)Assignments submitted by 11:59pm on Wednesday, April 22 will receive +7 bonus pointsNew Project File: For project 3 you will be using “STAT 201 – Spring 2020 – Project 3.jmp”. This file can be found on the STAT 201 webpage under the “Projects” tab.Getting Started: In this project, you will explore a subset (i.e., a sample) of some of the data collected from car engines created at KneeSun. You will be including a substantial amount of output within your write-up. INCLUDE ONLY THE OUTPUT NECESSARY TO ANSWER THE PROJECT QUESTIONS. This project file contains 600 responses. In real life situations, researchers would use all of the data they have available after conducting a survey. For this project, however, you will get JMP to help you take a random sample from the entire data set so that each student will have different results, and therefore will be turning in a UNIQUE project. The size of the random sample will be 300 plus the last two of your UT ID. If your student ID ends in 93, your sample size would be 393. When you create your random sample from the original JMP file, JMP creates a new file that will be named “Subset of STAT 201 – Spring 2020 – Project 3”. You should immediately save a copy of this file by clicking the “File” menu and choosing “Save As…”. JMP will prompt you to keep the same name, which is acceptable, or you can rename it to something like “Stat Project3 – My Data”.Taking Screenshots: Although there are many ways to get JMP graphics into a written presentation, we want you to use the “screen shot” method in all cases. Please see the video at for instructions on how to take selective screen shots on a PC or a Mac. Clearly label what question and part you are answering so your project is graded correctly but do not include question numbers! See page 4 for an example screenshot for a question.Tutorials and Write-up: See the JMP tutorials at Project 3 Playlist for instructions on how to get JMP to perform most tasks. Videos for each question can be found at the start of each question. In every question that asks you to produce output from JMP, we expect the output you produce to answer the question to be within the write-up. You should put this output immediately after your comments regarding that specific part of the assignment (i.e., not just a series of printouts from JMP at the back of your write-up). You can get help in the Stat 201 Lab with specific questions about the project. You can NOT ask a Stat 201 Lab worker to read your entire project for suggestions on what to change. Your finished work must be submitted within Canvas (see “Assignments”), and must be a Microsoft Word document (.doc or .docx).JMP and Hodges Library computers: Using JMP installed on your own computer is much simpler than using JMP on a library computer! If you choose to use a computer in the library to do your project, be sure to first read the document “Using JMP in the Library”, found in MyLab under the Project Files tab. Also, you will need to save your project and your random sample subset file to a location you can access later, such as a memory stick. You could also e-mail these files to yourself for later use.Writing a Good STAT 201 Project Report: Please take note that the last page of the instructions is a page titled “Writing a Good Stat 201 Project Report”. This page contains a series of guidelines for the written part of your report. A portion of your grade (10%) is related to following these guidelines.NOTE – Make sure to follow the guidelines of the project. This should look like a report delivered to the executives at the company. Make sure to watch the videos related to writing the executive summary and outro. (Click Here for Help Video)PromptKneeSun is a car company looking at investing in new machinery to build their engines. Each year KneeSun builds over 10,000 engines. New machinery is currently being tested by the company before purchasing. They’ve collected three different variables from some test results on the new and current machinery. The first variable is whether the engine was made on the new machinery verses their current machinery. The second variable is the engine life estimated in days the engine will last before needing repair. The final variable is collected from a safety test. If the engine fails this test, it cannot be used. It will cost $100,000 to upgrade. To make the upgrade KneeSun wants good evidence that the new engines will last longer and do better on the safety test than the current engines. Your report should clearly outline the data, the results and the decision KneeSun should make in the executive summary. The outro should focus on the importance of statistics in making data-driven decisions.Question One – Taking a Random SampleThe data for this project is found in the file “STAT 201 – Spring 2020 – Project 3.jmp”, which is located on the Stat 201 webpage under the “Projects” tab. From the full database, get JMP to help you take a random sample of size 300 plus the last two numbers on your UT ID. Save this file. You will be using this random sample data file, and the larger database, to answer the following questions. Make sure to use this random sample of 300 throughout the remainder of the project. (6 points)Question Two – Confidence Intervals for ProportionsCreate a pie chart using Analyze->Distribution in JMP. Put “Machine” in the “By” and “Test Results” in the “Y, Columns”. Include the graphic and interpret the percentages for the new and current machines. (6 points)To create a confidence interval for the true proportion, three conditions must be met. Clearly state the three conditions and whether they are met. (6 point)Create a 90% confidence interval for the true proportion of machines that are safe for only the current machines. Include the graphic and interpret the interval. (6 points)Create a 90% confidence interval for the true proportion of machines that are safe for only the new machines. Include the graphic and interpret the interval. (6 points)Question Three – Creating Histograms / Statistical Test on the MeanCreate a histogram and boxplot using Analyze->Distribution in JMP. Put “Machine” in the “By” and “Engine Life” in the “Y, Columns”. Include the graphic and interpret the distributions for the new and current machines. Make sure the histograms have a count axis, are in horizontal format and the quantiles and summary statistics are included to the right of the histograms. (6 points)The company is interested in the engines lasting more than 3,600 days on average. To perform a statistical test on the mean there are three conditions that must be met, write out the three conditions and clearly state whether or not they are met. (6 points)Write out the null and alternative hypothesis for testing the true mean of the engine life in statistical notation. Make sure to use proper symbols. (4 points)Perform a statistical test on the mean for the current machines. Clearly state your p-value and whether or not your reject or fail to reject the null. Your analysis should make clear to the reader of the report what your results indicate. (6 points)Perform a statistical test on the mean for the new machines. Clearly state your p-value and whether or not your reject or fail to reject the null. Your analysis should make clear to the reader of the report what your results indicate. (6 points)NOTE- For the next question you will need to make an Excel version of the random sample data set you created earlier. The following videos show how to export data to Excel.Exporting Data from JMP to Excel (MAC)Exporting Data from JMP to Excel (PC)Question Four – Confidence Interval for the MeanFrom the Excel version of your random sample data file, use Excel to calculate Summary Statistics and the margin of error for a 95% confidence interval for engine life. Use all engines in the data set for this confidence interval. Display within your report the Excel output you generated (it should look similar to the output shown on page 5 of this project). Use the margin of error Excel calculated to create a 95% confidence interval.6 points)Interpret your 95% confidence interval in context of the data. (6 points)A confidence interval can be used to perform a two-tailed test. Any value outside the interval is rejected at an alpha level of one minus the level of confidence for the interval. Are you able to reject the value of 3,600 days that was tested in the previous problem and if so, at what alpha level are you able to reject it at? (6 points)In research people hope to avoid Type I and Type II error. Given the alpha level is fixed at 0.05, give one suggestion the company could do to lower the probability of making a Type II error. (4 points)In context of your research on the engine life, what would a Type I error mean? Provide information to the executives to help them understand what decision this would lead to and what the error would be. (4 points)Additional point values:Project organization and flow (6 points)Projects should look neat and organized. Use the crop tool in Word if you need to improve screenshots. Your project should read like a report without the prompt of each question. Large blank spaces and images that have areas that should be cropped will lose 1 point per instance.Use of the guidelines on page 5 and the help video – (10 points) (Click Here for Help Video)The opening paragraph on the project should give an executive summary (4-6 sentences) of the analysis they’re about to read. The closing paragraph should focus on the importance of using statistics to make data-driven decisions. Make sure to use an opening and closing that is relevant to this project and your data.Example Excel Output Question 4(a) Writing a Good STAT 201 Project Report Writing a report to your boss about a statistical analysis he has asked you to do is very different than writing a novel, or writing to your Statistics instructor. What does it take to write a good project report? Of course, it’s important to know your audience when you write anything.Let’s assume you are writing your project report for some busy executives in the company, and they have asked you to answer the questions in the project. They are very intelligent people, but they are not “Statisticians”. Assume that these executives have had some basic statistical education, but perhaps a long time ago. Keep this in mind as you complete your project.Below are some guidelines for writing an effective project report:1.The first paragraph for the report should be an executive summary. The executive summary should be a 4-6 sentence summary that orients the reader and highlights the key points of the report. The goal of the executive summary in this report is to orient the read to the problem, explain key findings and then gives a solution or suggestion. Make sure mention findings by quoting numbers.2.Answer each question on the project instructions using correct sentence structure, spelling and grammar. Sentences should be succinct and clear. You can assume the executives have a copy of the questions they asked.3.Avoid using "statistical jargon". Explain the results of the analysis in a way that the executives can understand it.4.As explained in the project instructions, graphics from JMP and/or Excel that address the project question must be imbedded within the document, at the point where the executives need to see them. Don’t make them hunt for the output at the back of your report.5.The closing paragraph should mention the importance of statistics in research. Use your experience in this class to highlight the importance of data-driven decision making. The closing paragraph should be 4-6 sentences in length. ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download