2-a-First, consider a regression where the independent variable is the neighborhood income around a school attendance zone and the dependent variable is student test scores. What is the likely sign of the coefficient on neighborhood income?

b-Now consider a regression where the independent variable is a measure of violent crime incidents around the school and the dependent variable is student test scores. What is the likely sign of the coefficient on violent crime?

c-Finally, consider a regression of violent crime incidents on area income levels. What is the likely sign of the coefficient on area income levels?

d-Now consider the sign of omitted variable bias in the first regression, neighborhood income levels on student test scores. What is the sign of omitted variable bias if we omit a measure of violent crime around a school? Explain.

1319 school children were evaluated at age 12 and at age 14 for the prevalence of severe colds. There were 356 children who had severe colds at age 12, and 468 who had severe colds at age 14. There were 212 children who had severe colds at both ages. Do school children tend to have more severe colds when they are younger?

1. Build a two-way table displaying the information above.
2. Run McNemar’s test using the binomial distribution to see if there is sufficient evidence to conclude that school children are more likely to have severe colds at a younger age. Make sure to include all of the steps!
3. Repeat part (b) but use the function mcnemar.test() for these data.
4. Compare the p-values in parts b and c and explain any similarities (or differences).

A high school principal gathers a sample of the academic records of past and present high school scholarship basketball players at the high school. The principal reports that no significant difference was found in the mean GPA (grade point average) for male and female scholarship basketball players (P = 0.287). This means that

Question 1 options:

- the maximum difference in GPAs between male and female scholarship basketball player is 0.287.

- the GPAs for male and female scholarship basketball players are identical, except for 28.7% of the players.

- the chance that a pair of randomly chosen male and female scholarship basketball player would have a significant difference in GPAs is 0.287.

- the chance of obtaining a difference in GPAs between male and female scholarship basketball players as large as that observed in the sample if there is no difference in mean GPAs is 0.287.

TYPED ANSWER ONLY

A school psychologist wants to determine whether children who live with both parents perform better on school work than children who live with a single parent. She gathers two groups for her comparison, 20 children who live with both parents and another 20 who live with a single parent. The psychologist plans to use scores on a standardized achievement test as an indicator of school performance. Respond to the prompts below. (1 point each)

• What statistical test would be appropriate in this case? Explain the rationale for your answer.
• Identify the independent variable in this study.
• Identify the dependent variable in this study.
• Describe a potentially confounding variable and explain how that might affect the conclusions from the study.
• State the null and alternative hypotheses in words.

Random samples of employees in fast-food restaurants where the employer provides a training program were drawn. Of a sample of 67 employees who had not completed high school, 11 had participated in a training program provided by their current employer. Of an independent random sample of 113 employees who had completed high school but had not attended college, 27 had participated. Test at the 1% significance level the null hypothesis that the participation rates are the same for the two groups against the alternative that the rate is lower for those who have not completed high school.

Conduct the appropriate hypothesis test and report the p-value. Do not round intermediate calculations. Round your answer to four decimal places. Include the leading zero. Format: 0.0000

An IQ test scoring is designed to have mean of 100 and a standard deviation of 15. The scores are known to be normally distributed. A principal at a private school wants to investigate whether the average IQ of the students at her school is statistically different from the designed mean. She randomly samples from the school and has 15 students take the IQ test. The average test score of the sample is 95 and the sample standard deviation is 2. Use α = .10

1. Follow the 7 steps for hypothesis testing to solve this problem using the critical region method.

2. Calculate the p value.

3. Calculate the 90% confidence interval. Look to see if the hypothesized mean is in confidence intervals.

4. Do you come to the same conclusion using critical region, p value and confidence intervals?

The HR Department of Vanderizing Bulb Company wanted to know if among its salaried employees there was a relationship between years of school and annual compensation. A random sample of employees yielded the following data:

a. Find the correlation coefficient for the relationship between Years of School and Compensation.

b. Find the best equation which should be used to predict compensation on the basis of years of schooling. Justify by a test of a hypothesis.

c. Maggie Radford has 15 years of schooling. What is her predicted salary if she works at Vanderizing?

Problem 3-25 (Algorithmic) The College Board National Office recently reported that in 2011–2012, the 547,038 high school juniors who took the ACT achieved a mean score of 540 with a standard deviation of 122 on the mathematics portion of the test (http://media.collegeboard.com/digitalServices/pdf/research/2013/TotalGroup-2013.pdf). Assume these test scores are normally distributed.

What is the probability that a high school junior who takes the test will score no higher than 470 on the mathematics portion of the test? If required, round your answer to four decimal places.

P (x ≤ 470) =

What is the probability that a high school junior who takes the test will score between 470 and 550 on the mathematics portion of the test? If required, round your answer to four decimal places.

P (470 ≤ x ≤ 550) =

Imagine you are tasked with conducting a counseling intake interview with a 19 year old college student who is feeling sad, unmotivated, and worried about his grades. It is the student’s first semester at school, and he is finding that he has gone from being an A student in high school to a B- student in college. He has also moved 500 miles away from his hometown to attend school.

a number of counseling approaches (cognitive, humanistic, psychodynamic, and behavioral), that can be used to guide and understand an interview.

Which approach would you use to guide this intake interview? Explain why you think this approach is a good choice for this particular interview also, develop at least 5 questions for your interview and explain how the questions fit with the approach you chose.

The School District of Philadelphia wants to encourage teachers to fill out an “end-of-year” survey designed to elicit their feedback about various issues affecting schools. The survey is one of the primary channels through which the school district learns about what is happening in schools across the city, and increasing engagement is a key policy priority for the city. The School District has already created the survey and plans to send out the survey in an email to its 8,062 teachers. The District is willing to manipulate the messaging content in the email that will be sent out and/or provide rewards and incentives for survey completion. (They have up to $3,000 to spend.) Using your knowledge of behavioral economics, what would you suggest they do to maximize survey response rates? Be as specific as possible and justify your choices.