A study is being conducted to compare the average training time for two groups of airport security personnel: those who work for the federal government and those employed by private security companies. From a random sample of 12 government-employed security personnel, average training time was 72 hours, with a sample standard deviation of 8 hours. In a random sample of 16 privately employed security personnel, training time was 65.4 hours, with a sample standard deviation of 12.3 hours. Assume that training time for each group is normally distributed. Use the following notations: μ1: The mean training time for the population of airport security personnel employed by the federal government. μ2: The mean training time for the population of airport security personnel employed by private security companies. The goal of the statistical analysis is to determine whether the sample data support the hypothesis that average training time for government-employed security personnel is higher than those employed by private security companies. Question 21 What is the null hypothesis H0? Select one: a. μ1- μ2 ≤ 0 b. μ1- μ2 < 0 c. μ1- μ2 ≠ 0 d. μ1- μ2> 0 Question 22 What is the alternative hypothesis Ha? Select one: a. μ1- μ2 > 0 b. μ1- μ2 ≤ 0 c. μ1- μ2 = 0 d. μ1- μ2 ≥ 0 Question 23 What is the standard error of ( x(bar)1 - x(bar)2 )? Select one: a. 2.30 b. 4.30 c. 3.85 d. 5.29 Question 24 What is the value of the test statistic? Select one: a. 1.71 b. 1.35 c. 0.65 d. 1.22 Question 25 What is the p-value? Select one: a. 0.30 b. 0.05 c. 0.26 d. 0.12 Question 26 At α=0.1 and using the p-value Select one: a. We reject H0 in favor of Ha b. We do not reject H0
From the given information,
By using calculator,
The required correct answers are,
1. Ho:- a. μ1- μ2 ≤ 0
2. Ha:- a. μ1- μ2 > 0
3. standard error of ( x(bar)1 - x(bar)2 )= 3.85
4. test statistic= 1.71
5. p-value=b. 0.05
6. a. We reject H0 in favor of Ha
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A study is being conducted to compare the average training time for two groups of airport...
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