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A fellow student says that the average salary of graduates in your major is 30,000 dollars per year. You don’t think that this is correct. You think that the average salary is different from this. To show that your fellow student is wrong, you take a simple random sample of fifty graduates who have graduated in the past 5 years and ask for the amount of their starting salary. We want to investigate whether there is evidence to support your claim that the population mean starting salary is different from 30,000 and find that the p-value is 0.03.    What can be said about the 95% confidence interval for the population mean difference?

Suppose that a doctor wants to determine if a new exercise plan helps lower participants’ blood pressure levels. The blood pressure level for each participant is recorded for each participant before beginning the program. Each of the participants then participates in the new exercise plan for 6 weeks. Then blood pressure is then taken again. Let mu_d = the average blood pressure before – average blood pressure after. What is the correct alternative hypothesis?

An instructor was interested in studying students satisfactory solving of a math problem. The students were given a math problem to solve before and after instruction. Each time, the student was given either a “S” for satisfactory completion or “U” for unsatisfactory completion. Two hundred randomly selected students were involved in the study. “S” after instruction “U” after instruction “S” before instruction 99 14 “U” before instruction 12 75  Besides random sampling and categorical data, what other assumption needs to be met? Is it met?

Is the mean nursing salary for men and women with similar experience statistically significantly different? A significance test was conducted to test this claim. The p-value was 0.03. What can be said about the 95% confidence interval for the population mean difference?

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?