Paleo diet allows only for foods that humans typically consumed over the last 2.5 million years, excluding those agriculture-type foods that arose during the last 10,000 years or so. Researchers randomly divided 500 volunteers into two equal-sized groups. One group spent 6 months on the Paleo diet. The other group received a pamphlet about controlling portion sizes. A randomized treatment assignment was performed, and at the beginning of the study, the average difference in weights between the two groups was about 0 pounds. After the study, the Paleo group had lost an averag

This question refers to excavations at a national monument. One question the archaeologists asked was: Is raw material used by prehistoric Indians for stone tool manufacture independent of the archaeological excavation site? Two different excavation sites gave the information in the following table. Use a chi-square test with 5% level of significance to test the claim that raw material used for construction of stone tools and excavation site are independent. Stone Tool Construction Material Material Site B Row Total Basalt 768 547 1315 Obsidian 101 94 195 Pedernal chert Other Column Total 536 499 1035 179 1496 1228 2724 (a) What is the level of significance? State the null and alternate hypotheses. O Ho: Stone tool material and site are independent. H: Stone tool material and site are not independent. O Ho: Stone tool material and site are not independent. H: Stone tool material and site are independent. O Ho: Stone tool material and site are independent. H: Stone tool material and…

A food-frequency questionnaire is used to measure dietary intake. The respondent specifies the number of servings of various food items they consumed over the previous week. The dietary cholesterol is then quantified for each respondent. The researchers were interested in assessing if there was an association between dietary cholesterol intake and high blood pressure. In a large sample of individuals who had completed the questionnaire, 250 persons with a high dietary cholesterol intake (greater than 300 mg /day) were selected and 250 persons with a low dietary cholesterol intake (less than 300 mg/day) were selected. The 500 selected participants had their medical history taken and were classified as having normal or high blood pressure. The data are given here. Dietary Cholesterol Blood Pressure Total High Low High 159 91 250 Low 78 172 250 Total 237 263 500 Test 2: two-tailed test for comparing two independent proportions Clearly state…

The General Social Survey (GSS) collects data on demographics, eduction and work, among many other characteristics of US residents. Suppose we want to estimate the difference between the average number of hours worked by all Americans with a college degree and those without a college degree. Is there sufficient evidence that there is a significant difference between the average number of hours worked by those Americans with a college degree vs. those Americans without a college degree? Use the following output: Welch Two Sample t-testdata:  yes and not = 3.1181, df = 1098.5, p-value = 0.001867alternative hypothesis: true difference in means is not equal to 095 percent confidence interval: 1.011652 4.445822sample estimates:mean of x mean of y  42.81574  40.08701 Using the provided output, find the 95% confidence interval for the difference of the average amount of hours worked for those that have a college degree vs. those that do not have a college degree (ie: for the difference of two…