You volunteer some of your spare time to your local fire department and have been asked by an assistant chief to analyze data on firefighters who applied for promotion. The assistant chief wants to ensure that gender bias is not a concern in the promotion of firefighters. Shown below is data for 50 firefighters who applied for promotion and the results of a chi-square analysis of the data.   Male Female Promoted 13 22 Not Promoted 10 5   Chi-Square Statistic 3.6845 P value 0.054919       Is the promotional status of recently promoted firefighters independent of their gender? What reasons should the assistant chief convey to the fire chief to justify the absence of gender bias in the most recent class of firefighters who were promoted?

Health insurance benefits vary by the size of the company (the Henry J. Kaiser Family Foundation website, June 23, 2016). The sample data below show the number of companies providing health insurance for small, medium, and large companies. For the purposes of this study, small companies are companies that have fewer than 100 employees. Medium-sized companies have 100  to 999  employees, and large companies have 1000  or more employees. The questionnaire sent to 225  employees asked whether or not the employee had health insurance and then asked the employees to indicate the size of the company.   Health Insurance   Size of Company Yes No Total     Small 33 17 50     Medium 67 8 75     Large 89 11 100   Conduct a test of independence to determine whether health insurance coverage is independent of the size of the company. What is the p-value? Compute the value of the x2 test statistic (to 2 decimals)  A newspaper article indicated…

Pain medications sometimes come with side effects. One side effect is dizziness. A researcher wanted to determine if some pain medications produced more or less dizziness than others. The results from his study are shown in the table below. Use a test to determine if the proportion of people within each treatment group who experienced dizziness are the same at the a = .01 level of significance. Tordol Placebo Naproxen Tylenol Advil Dizziness 83 32 36 No dizziness 4063 1832 1330 382 337 1) Determine the null and alternative hypotheses. Select the correct pair. OH,: The proportion of people within each treatment group who experienced dizziness are the same Ha: The proportion of people within each treatment group who experienced dizziness are different OH,:The proportion of people within each treatment group who experienced dizziness are independent Ha: The proportion of people within each treatment group who experienced dizziness are dependent 2) Determine the test Statistic. Round your…

A marketing firm is doing research for an internet-based company. It wants to appeal to the age group of people who spend the most money online. The company wants to know if there is a difference in the mean amount of money people spend per morith on Internet purchases depending on their age bracket. The marketing firm looked at two age groups, 18-24 years and 25-30 years, and collected the data shown in the following table. Let Population 1 be the amount of money spent per month on internet purchases by people in the 18-24 age bracket and Population 2 be the amount of money spent per month on internet purchases by people in the 25-30 age bracket. Assume that the population variances are not the same. Internet Spending per Month 18-24 Years Answer Mean Amount Spent Standard Deviation Sample Size Step 1 of 2: Construct a 99 % confidence interval for the true difference between the mean amounts of money per month that people in these two age groups spend on Internet purchases. Round the…

Only letters C and D

The height (in feet) and trunk circumference (in inches) at breast height (4.5 feet above the ground)was measured for a random sample of Eucalyptus trees. The data are summarized below.Trunk Circumference 21.1 20.8 22.5 19.4 23.6 19.8 21.6 19.9Tree Height 34.2 32.7 35.0 31.9 36.5 31.2 33.8 31.4(a) Determine the linear regression model that will best predict the height of a Eucalyptus treebased on its trunk circumference at breast height.

I need help with something regarding this problem.  The National Sleep Foundation recommends that adults aged 18 to 64 get an average of 8 hours of sleep per night. A survey of sleep hours was taken during a Statistics class. The data is listed below:   4, 5, 5, 5, 5.5, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 9, 9, 9, 10, 10   Do we have enough evidence at the 0.05 significance level to say that statistics students tend to get less sleep than the recommended average of 8 hours per night?   How would I get the degrees of freedom?

Suppose the National Transportation Safety Board (NTSB) wants to examine the safety of compact cars, midsize cars, and full-size cars. It collects a sample of cars each of the cars types. The data below displays the frontal crash test performance percentages. Test whether there are statistical differences in the frontal crash test performance for each type of car.   Car Sizes Compact Cars Midsize Cars Full-Size Cars 95 95 93 98 98 97 87 98 92 99 89 92 99 94 84 94 88 87 99 93 88 98 99 89 What conclusions can we draw from the follow-up t-tests?   There is/are a total of  ______ statistically significant difference(s) between car type pairs out of the follow-up t-tests.  Options: a) 1 b) 2  c) 3 d) 4 e) 5 f) 6

Health insurer benefits vary by the size of the company. The sample data below show the number of companies providing health insurance for small, medium,  and large companies. For the purpose of this study,  small companies are companies that have fewer than 100 employees.  Medium-sized companies have 100 to 999 employees,  and largevcompanies have 1000 or more employees.  The questionnaire sent to 225 employees asked whether or not the employee had health insurance and then asked the employee to indicate the size of the company.                       Health Insurance  Size of company  Yes     No    Total Small.                      35       15       50 Medium                   67        8        75 Large                        87     13       100 A. Conduct a test of independence to determine whether health insurance coverage is independent of the size of the company.  What is the p-value? Compute the value of the x2 test statistic (to 2 decimal)

Pain medications sometimes come with side effects.  One side effect is dizziness.  A researcher wanted to determine if some pain medications produced more or less dizziness than others.  The results from his study are shown in the table below. Use a test to determine if the proportion of people within each treatment group  who experienced dizziness are the same at the � = .01 level of significance.   Tordol Placebo Naproxen Tylenol Advil Dizziness 83 32 36 5 8 No dizziness 4063 1832 1330 382 337 1) Determine the null and alternative hypotheses. Select the correct pair.   ��:The proportion of people within each treatment group  who experienced dizziness are independent��: The proportion of people within each treatment group  who experienced dizziness are dependent ��: The proportion of people within each treatment group  who experienced dizziness are the same��: The proportion of people within each treatment group  who experienced dizziness are different   2) Determine the…