Kiss Data Link
Lab 3 - "Bad Food" Matters In this lab you will compare means and variances between two varieties of Kisses@ and investigate Hershey's manufacturing processes. Next, you'll run a "goodness of fit" test on the Mars@ Company's claim of color percentages in their M&M's@ (this will require a small purchase). Finally, you'll answer some questions on sampling and tests of independence after you read a recent article from Time magazine on whether butter is as bad as we were led to believe. Follow the instructions carefully. On some problems you will need to show all your work, step by step, and write a final summary analysis before submitting everything to the Lab 3 - Drop Box. Submit and Excel file that includes your Data and scan your written work to one pdf file. If you do not have a scanner there are apps available for your phone. See Dropbox instructions or the course syllabus. or you can even photograph it with your cell phone. NOTE: One of the several things I want to accomplish in lab activities is to give you some practice with writing out hypothesis tests completely from start to finish. On-line homework software by its very nature must ask you a series of questions "leading" you through the problem. It does this so that you get your answers in the right "boxes" to be electronically graded. This can be deceptive in a way since on the exams you're expected to run hypothesis tests from scratch as demonstrated in the video examples. It's a good idea to keep this in mind when you are doing the homework. Work the hypothesis tests out and then answer the questions from your results. The following problems will practice you in this and provide me with an opportunity to give you some feedback Make sure when you run your tests to state the null and alternative Hypothesis correctly using the correct notation and show all your work. Part 1 - The Great Kiss Off - Investigating the variance between two varieties of Hershey Kisses@ Investigate two varieties of Kisses: Hershey Kisses with Almonds and Regular Hershey Kisses. Click Once for Excel file: Kiss Data Means (Section 8.2) a) Run a test to see if the mean weights are different. What are the populations and population parameters? (Use correct notation when you define the parameters) b) What are the sample estimates of these parameters? (Use correct notation when you define the sample estimates) c) Set up the correct null and alternative hypotheses and run the test to determine if the mean weights are different. alpha = .05 d) What is your conclusion concerning the difference between the populations means? Variances (Section 8.6) e) Run a test to see if the variances are different between the two populations. What are the population parameters? (Use correct notation when you define the parameters) f) What are the sample estimates of these parameters? (Use correct notation when you define the sample estimates) g) Set up the correct null and alternative hypotheses and run the test to determine if the variance in weights are different between the two populations. Run this test by hand, showing all your work using the formulas to compare a Test Statistic to a critical value (rejection region). Let alpha = .0 h) Run this test using Excel by finding a p-value. i) What is your conclusion concerning the difference in the variances? Overall Conclusion for Part 1 Look carefully at the picture above. The 3 Kisses on the left are Hershey Kisses with Almonds and the 3 on the right are Regular Hershey Kisses. j) Which ones look bigger? Were you able to prove a difference in their "weights" (masses)? Explain what this might suggest. k) If there is a difference in variances, what might this imply about the processes that make the Kisses? Look at the pictures and take some time to think about this
