Lesson 9: Comparing Two Groups Lab Activity 9 NAME: Lori Levinson Due Friday March 25 by 11:55 PM EST, a 24 hours graceful period will be given for this assignment. The dropbox will be closed at Saturday Midnight (March 26) Directions. This lab pertains to materials covered in Lesson 9 (\"Comparing Two Groups\"), particularly Chapter 10 in the textbook. The assignment should be typed, with your name on the document. \"Class Survey\" dataset is needed for this activity. If you choose to collaborate, the write-up should be your own. Please show your work! Upload a word file to the Lab 9 Dropbox on ANGEL by the deadline. One Bonus Question (20 pts) is optional at the end of this assignment. 1. [30 pts] Selecting an appropriate procedure to conduct the hypothesis testing. For each of the following research questions, you will be asked to determine (1) what is an appropriate test procedure (a single proportion, single mean, paired means, independent proportions, or independent means?) (2) Using proper statistical notations to write down the null hypothesis and alternative hypothesis. (3) Identify the tail of the test (right-tail, left-tail, or two tails). a. Twenty-five people have their cholesterol measure before eating a Big Mac and again after eating a Big Mac. On average, does eating a Big Mac increase cholesterol? b. Penn State admission office collected the data to investigate whether the average GRE math scores for UP students are higher than 600. c. What is the difference in average salaries for high school graduates and college graduates? d. In a marketing survey for the sales of iphone 6s product, among 1000 randomly selected customers from BestBuy store in state college, there are 350 customers purchasing iphone 6s. What is the estimate purchase rate for iphone 6s? How does it compare to the 54% purchase rate of iphone 6 last year? [Hint: you can consider it either in one population or two population problems] e. In fifty married couples, the husband and wife each separately take the same test of marital satisfaction. Is there a difference, on average, between the scores of husbands and wives? f. According to the Bureau of Labor Statistics, the official unemployment rate was 15.5% among Blacks and 7.9% among Whites as of March 2011. A sociologist conducted a research to investigate whether there is a racial bias among Blacks and Whites on the unemployment rate. 2. [30 pts] Comparing Population Means for Two Groups In the Datasets folder in ANGEL open the Class Survey dataset. The variable Gender indicates whether respondents were female or male students. We'll compare the mean number of parties attended per month (Monthly Parties is the variable) for female students versus male students to see if males have a higher propensity for partying. a. [2 pts] In words, write a null hypothesis for this situation. We're comparing two means (number of parties attended monthly for female students versus male students.) [Hint: State the null hypothesis in words] 1 Lesson 9: Comparing Two Groups Lab Activity 9 NAME: Lori Levinson b. [2 pts] Consider female students to be population 1 and male students to be population 2. Using statistical notation for means, write null and alternative hypotheses for this problem [Hint: state the null hypothesis and alternative hypothesis in statistical notations]. c. [6 pts] Recall from the lecture notes that when doing a two-sample t-test, consideration should be made to determine whether the two standard deviations (or variances) are equal. To check, use software to find the standard deviation for Monthly Parties for the two categories of Gender status. [Hint: In Minitab, you can get these SD by Stat > Basic Statistics > Display Descriptive and select Monthly Parties for Variables and Gender for By Variables.] i.[2 pts] What are the two standard deviations? Copy and paste the relevant output. Std.dev for female students: Std.dev for male students: ii. [2 pts] Is the larger standard deviation more than twice the smaller standard deviation? iii. [2 pts] If your answer to part ii is \"Yes\