For statistical studies, U.S. states are often grouped by region: Northeast, Midwest, South, and West. The 1965 total public school enrollment (in millions) in each region was 8.8, 11.8, 13.8, and 7.6, respectively. The projected 2020 enrollment was 7.8, 10.8, 20.4, and 13 .6, respectively. Use two pie graphs to present this data and discuss any trends suggested by your graphs.

A basic finding of labor economics is that workers who have more experience in the labor force are paid more than workers who have less experience (holding constant the amount of formal education). Why might this be so? Some studies have also found that experience at the same job (called job tenure) has an extra positive influence on wages. Explain.

In the 1960s, children entering the Willowbrook State School, an institution for the intellectually disabled on Staten Island in New York, were deliberately infected with hepatitis. The researchers argued that almost all children in the institution quickly became infected anyway. The studies showed for the first time that different strains of hepatitis existed. This finding contributed to the development of effective vaccines. Despite these valuable results, explain why this study was unethical.

Studies show that women tend to use a $\_\_\_\_\_\_\_\_\_\_\_$ style to their conversation, while men use a $\_\_\_\_\_\_\_\_\_\_\_$ style.

a. relate; report             c. masculine; feminine b. report; relate             d. androgynous; stereotypical

Studies show that when environmental factors impose an upper bound on the possible size of a population $P(t)$, the population often tends to grow in such a way that the percentage rate of change of $P(t)$ satisfies

$$\frac{100 P^{\prime}(t)}{P(t)}=A-B P(t)$$

where $A$ and $B$ are positive constants. Where does the graph of $P(t)$ have an inflection point? What is the significance of this point? (Your answer will be in terms of $A$ and $B$.)

The Organization for Economic Cooperation and Development (OECD) conducts studies on unemployment rates by country and publishes its findings in the document Main Economic Indicators. Independent random samples of 100 and 75 people in the civilian labor forces of Finland and Denmark, respectively, revealed 7 and 3 unemployed, respectively, Find a 95% confidence interval for the difference between the unemployment rates in Finland and Denmark.

Several studies have found a correlation between the activity levels of brown fat tissue in research participants following exposure to cold and their percentage of body fat . Devise a graph that would present the results from such a study, labeling the axes and drawing a line to show whether the results show a positive or negative correlation between the variables. Propose two hypotheses that could explain these results.

When Lux studies her psychology terms, she tries to tie each concept into something she already knows. She thinks about the meaning of the concept rather than just saying the words over and over. Which of the following best explains Lux's approach to encoding memories? a. information-processing model b. levels-of-processing model c. selective attention d. maintenance rehearsal

In 2007, the FDA announced that the popular drug Zelnorm used to tr eat irritable bowel syndrome was withdrawn from the market , citing concerns about serious side effects. The analysis of several studies revealed that 13 of 11,614 patients receiving the drug had a serious side effect such as heart attack or stroke, compared to just 1 out of 7,031 on placebo.

Compute the odds ratio and interpret.

Throughout the country, the proportion of first-time, first-year community college students who return for their second year of studies is 0.52 according to the Community College Survey of Student Engagement. Suppose a community college institutes new policies geared toward increasing student retention. The first year of this policy there were 2843 first-time, first-year students of which 1516 return ed for their second year of studies. Treat these students as a random sample of all first-time, first-year students. Do a statistically significant higher proportion of students return for their second year under this policy? Use the $\alpha$=0.1 level of significance. Would you say the results are practically significant? In other words, do you believe the results are significant enough that other community colleges might consider emulating these same policies?

Studies have shown that a positive association exists between educational level and annual salary; in other words, people with more education tend to make more money. a. Does this finding mean that more education causes a person to make more money? Explain your answer. b. Do you think there is a causal relationship between educational level and annual salary? Explain your answer.

Many medical studies have tried to prove that smoking causes lung cancer. a. Is smoking a necessary condition for lung cancer? Why or why not? b. Is smoking a sufficient condition for lung cancer? Why or why not? c. Is there a correlation between people who smoke and people who get lung cancer? Explain your reasoning. d. Is it true that smoking causes lung cancer? If so, how was it proven?

An ornithologist, someone that studies birds, put radio tags on two birds and released them at the same time from the same place to study their migration. After two days, one bird was 27 miles away at 210 degrees southwest and the other was 22 miles away at 120 degrees southeast. How far apart were the birds from each other, to the nearest tenth of a mile?

Many medical studies have tried to prove that smoking causes lung cancer.

a. Is smoking a necessary condition for lung cancer? Why or why not?

b. Is smoking a sufficient condition for lung cancer? Why or why not?

c. Is there a correlation between people who smoke and people who get lung cancer? Explain your reasoning.

d. Is it true that smoking causes lung cancer? If so, how was it proven?