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Let alpha = 0.05. Suppose that you were testing Ho:mu = 30 versus Ha: mu greater than 30. If you had a p-value of 0.07, what decision would you make?

A political scientist is interested in studying how Americans feel about having a female American president. He asks 100 males(1) and 100 females(2) if they would vote for a women president. Is there a significant difference in how women and men would vote? What would be the correct alternative hypothesis?

A famous weight loss program was involved in a study to determine if their current weight loss program scheme was effective. They randomly selected 15 participants and took their weight before the program and then six weeks later. They then took the before weights – after weights and made a confidence interval. The 95% confidence interval was (-1.3, -4.5).  Finish the following sentence “We are 95% confident that the [word1]weight before the program was between 1.3 [word2] to 4.5 [word3] then after the program.

Researchers were trying to determine if a connection could be made between whether choice of musical instruments and gender. They want to see whether more men (m) play the flute than women (f). What would be the correct alternative hypothesis?

A nutritionist was interested in studying American’s opinions about healthy living. One hundred randomly selected people who were starting a diet were asked if they consumed at least 24 ounces of water a day. After six months, the same 100 people were asked if they consumed at least 24 ounces of water a day   Six months later “Yes, consumed at least 24 ounces of water” Six months later “No, did not” Initial Response “Yes, consumed at least 24 ounces of water” 25 20 Initial Response “No did not” 40 15   What is the sample proportion of people who responded “No, they did not consume at least 24 ounces of water” six months later?

The General Social Survey first randomly selected men and women. Then, they asked 320 men and 306 women if they felt that they knew at least quite a bit about politics. Out of 320 men, 106 said that they felt that they knew quite a bit about politics and out of 306 women, 76 said that they felt that they knew quite a bit about politics. Suppose that you want to make a 95% confidence interval for , what assumption is violated in this case?

Two hundred people were randomly selected in the year 2010 (group 1) and in the year 2012 (group 2). They were asked how many hours a day they spent listening to a radio. The sample mean in 2010 was 1.36 hours and in 2012 it was 1.32 hours. What is the point estimate of the population mean difference between 2010 and 2012?

In 2000, General Social Survey respondents were asked “How many hours did they spend on their personnel computer per week?”. The researchers were interested in seeing if men (1) spent more time on the personnel computer then women (2).  For this hypothesis, the p-value was 0.0169. Interpret.

A scientist was interested in determining if the Paleo diet plan worked.  They randomly selected 4 people that were interested in trying a new diet plan. They recorded their initial weights before starting the diet plan. After six weeks, their weight was taken again. How would you check the normality assumptions for this test?     1 2 3 4 Initial weight 150 167 129 194 Weight six weeks later 172 157 124 190

In the US, the allowable amount of mercury in drinking water is 2 parts per 1000 Liters. Water from 5 randomly selected homes was taken. The amount of mercury in the water is below. A scientist wants to test to see if the amount of mercury is unsafe. These measurements are also in parts per 1000 Liters. 0 0.5 0.5 0.5 1   Find the standard error that would be used in the test statistic to test this claim.