A school district has a standardized test that it uses to sort students into magnet schools, where the test is on a 200-point scale. The superintendent is looking to determine whether male and female students have approximately equal scores on the test. The scores for a random sample of 20 male students and 20 female students are recorded. Assume that the population variances of scores for male and female students are equal and that the scores are normally distributed for both male and female students. Let the male students be the first sample, and let the female students be the second sample.

The superintendent conducts a two-mean hypothesis test at the 0.05 level of significance, to test if there is evidence that male and female students have different scores, on average.

For this test: H0:μ1=μ2; Ha:μ1≠μ2, which is a two-tailed test.

The above table contains scores for a random sample of 20 male students and 20 female students.

Use a TI-83, TI-83 Plus, or TI-84 calculator to test if there is evidence that male and female students have different scores, on average. Identify the test statistic, t, and p-value from the calculator output. Round your test statistic to two decimal places and your p-value to three decimal places.

test statistic =? , p-value = ?

6. Researchers obtained a sample of 36 college students who all have the same history instructor this semester. Half of the students were shown a 2-min video that claimed the purpose of education was to help students “learn how to learn” so that they can enjoy a lifetime of learning after college. The other half of students were shown a 2-min video that claimed the purpose of education was to teach facts to students. After watching the 2-min videos, the students were asked to rate their history instructor using a 10-point scale, 1 = very bad teacher to 10 = very good teacher. The mean and standard deviations for each group of 18 students are provided below. Use the provided information to answer the next four questions. Use an α of .05, two tailed.

“learn to learn” Group 1: M₁ = 5.9, SD₁ = 1.8, n₁ = 18

“learn facts” Group 2: M₂ = 7.2, SD₂ = 1.7, n₂ = 18

Compute the independent t-test

7. Researchers obtained a sample of 36 college students who all have the same history instructor this semester. Half of the students were shown a 2-min video that claimed the purpose of education was to help students “learn how to learn” so that they can enjoy a lifetime of learning after college. The other half of students were shown a 2-min video that claimed the purpose of education was to teach facts to students. After watching the 2-min videos, the students were asked to rate their history instructor using a 10-point scale, 1 = very bad teacher to 10 = very good teacher. The mean and standard deviations for each group of 18 students are provided below. Use the provided information to answer the next four questions. Use an α of .05, two tailed.

“learn to learn” Group 1: M₁ = 5.9, SD₁ = 1.8, n₁ = 18

“learn facts” Group 2: M₂ = 7.2, SD₂ = 1.7, n₂ = 18

The researchers in this study should:

8. Researchers obtained a sample of 36 college students who all have the same history instructor this semester. Half of the students were shown a 2-min video that claimed the purpose of education was to help students “learn how to learn” so that they can enjoy a lifetime of learning after college. other half of students were shown a 2-min video that claimed the purpose of education was to teach facts to students. After watching the 2-min videos, the students were asked to rate their history instructor using a 10-point scale, 1 = very bad teacher to 10 = very good teacher. The mean and standard deviations for each group of 18 students are provided below. Use the provided information to answer the next four questions. Use an α of .05, two tailed.

“learn to learn” Group 1: M₁ = 5.9, SD₁ = 1.8, n₁ = 18

“learn facts” Group 2: M₂ = 7.2, SD₂ = 1.7, n₂ = 18

Compute the effect size of this study.

9. Researchers obtained a sample of 36 college students who all have the same history instructor this semester. Half of the students were shown a 2-min video that claimed the purpose of education was to help students “learn how to learn” so that they can enjoy a lifetime of learning after college. The other half of students were shown a 2-min video that claimed the purpose of education was to teach facts to students. After watching the 2-min videos, the students were asked to rate their history instructor using a 10-point scale, 1 = very bad teacher to 10 = very good teacher. The mean and standard deviations for each group of 18 students are provided below. Use the provided information to answer the next four questions. Use an α of .05, two tailed.

“learn to learn” Group 1: M₁ = 5.9, SD₁ = 1.8, n₁ = 18

“learn facts” Group 2: M₂ = 7.2, SD2 = 1.7, n₂ = 18

How large is the effect size?

10. Researchers obtained a sample of 36 college students who all have the same history instructor this semester. Half of the students were shown a 2-min video that claimed the purpose of education was to help students “learn how to learn” so that they can enjoy a lifetime of learning after college. The other half of students were shown a 2-min video that claimed the purpose of education was to teach facts to students. After watching the 2-min videos, the students were asked to rate their history instructor using a 10-point scale, 1 = very bad teacher to 10 = very good teacher. The mean and standard deviations for each group of 18 students are provided below. Use the provided information to answer the next four questions. Use an α of .05, two tailed.

“learn to learn” Group 1: M₁ = 5.9, SD₁ = 1.8, n₁ = 18

“learn facts” Group 2: M₂ = 7.2, SD₂ = 1.7, n₂ = 18

Compute 95% CI for the mean difference between the “learn how to learn” and “teach facts” groups.

Quiz 9 STUDY QUESTIONS

1 For each of the following statements, indicate whether the statistical association is likely the result of chance, confounding. bias. or A case-control study showed that a strong association exists between birth order and Down syndrome.

b. A case-control study lound a positive association between self-reported chest radiographs during pregnancy and breast cancer. A randomized clinical trial found that drug A versus placebo did not significantly improve 10-year survival (RR = 0.35; 95% confidence interval, 01455014 A cohort study found no statistical association between smoking and pancreatic cancer (RR = 1: = P value = 0.85). A hospital-based case-control study identified a strong association between oral contraceptives and thromboembolism. Many doctors suspected the association and hospitalized some women who used oral contraceptives for evaluation

2 Match the following methods for minimizing chance, bias, and confounding in an experimental study Chance Bias Confounding a Randomization b. Blind c. Increase sample size

3. Recall the causal criteria presented by Sir Austin Brad- ford Hill in 1965 Discuss these criteria in the context of smoking and lung cancer.

4.Suppose you suspect based on descriptive epidemiol ogy that college students who perform better aca demically are more likely to have an office job and be obese 10 years after graduation. You decide to select 500 graduating seniors randomly and classify them according to grade point average as high versus low (where the cut point is at the median of the GPAs for these students). The resulting 2 x 2 contingency table is as follows: Below is a table GPA High Low Total Obese at 10 Years Yes 60 40 100 No 190 210 400 Total 250 250 500 Apply this data to the six steps of hypothesis.

5. Match the following Predisposing factors Enabling factors Precipitating factors Reinforcing factors a Facilitate manifestation of a disease le housing) Associated with definitive onset of disease (eg. toxin Increase level of susceptibility m a host of age) d. Aggravate presence of disease leg repeated exposure)

6. Compare a direct causal association with an individual causal association. Use specific examples

7. Define and compare the difference between static inference and causal inference. 8. Why might studying a sample be preferred population? A component cause is also called which of the following?

a. Risk factor b. Web of causation c. Epidemiologic triangle

d. Each of the above are component causes 10 Webs of causation play a more useful role when one is trying to describe disease etiology for which type of disease? a. Acute b. Infectious C. Chronic d. Two of the above.

The mean number of eggs per person eaten in the United States is 234. Do college students eat more eggs than the average American? The 65 college students surveyed averaged 248 eggs per person and their standard deviation was 92.4. What can be concluded at the α = 0.01 level of significance? For this study, we should use The null and alternative hypotheses would be: H 0 : H 1 : The test statistic = (please show your answer to 3 decimal places.) The p-value = (Please show your answer to 4 decimal places.) The p-value is α Based on this, we should the null hypothesis. Thus, the final conclusion is that ... The data suggest that the sample mean is not significantly more than 234 at α = 0.01, so there is not enough evidence to conclude that the sample mean number of eggs consumed by college students per year is more than 248. The data suggest that the population mean is not significantly more than 234 at α = 0.01, so there is not enough evidence to conclude that the population mean number of eggs consumed by college students per year is more than 234. The data suggest that the populaton mean is significantly more than 234 at α = 0.01, so there is enough evidence to conclude that the population mean number of eggs consumed by college students per year is more than 234. Interpret the p-value in the context of the study. There is a 11.3178436% chance that the population mean number of eggs consumed by college students per year is greater than 234 . There is a 11.3178436% chance of a Type I error. If the population mean number of eggs consumed by college students per year is 234 and if another 65 college students are surveyed then there would be a 11.3178436% chance that the sample mean for these 65 students surveyed would be greater than 248. If the population mean number of eggs consumed by college students per year is 234 and if another 65 students are surveyed then there would be a 11.3178436% chance that the population mean number of eggs consumed by college students per year would be greater than 234. Interpret the level of significance in the context of the study. There is a 1% chance that you will find the chicken that lays the golden eggs. If the population population mean number of eggs consumed by college students per year is more than 234 and if another 65 college students are surveyed then there would be a 1% chance that we would end up falsely concluding that the population mean number of eggs consumed by college students per year is equal to 234. If the population mean number of eggs consumed by college students per year is 234 and if another 65 college students are surveyed then there would be a 1% chance that we would end up falsely concluding that the population mean number of eggs consumed by college students per year is more than 234. There is a 1% chance that the population mean number of eggs consumed by college students per year is more than 234.

Create the following java program with class list that outputs:

//output

List Empty
List Empty
List Empty
Item not found
Item not found
Item not found

Original list
Do or do not. There is no try. 

Sorted Original List
Do There do is no not. or try. 

Front is Do
Rear is try.
Count is 8
Is There present? true
Is Dog present? false

List with junk
junk Do or moremorejunk do not. There is no try. morejunk 
Count is 11

List with junk removed
Do or do not. There is no try. 
Count is 8

List Full
List Full
List Full
List Full
List Full
List Full

After filling List
dummy dummy dummy dummy dummy dummy dummy Do or do not. There is no try. 
Count is 15

After removing dummy
Do or do not. There is no try. 
Count is 8

// main

public class AssignmentThree
{
   public static void main(String[] args)
   {
       List myList = new List(15);
      
       // Cause List Empty Message
       myList.removeFront();
       myList.removeRear();
       myList.removeItem("a");
      
       // Cause Not found message
       myList.addToFront("x");
       myList.removeItem("y");
       myList.removeItem("x");
       myList.addAfterItem("x", "z");
       myList.addBeforeItem("x", "z");
          
       // Normal behavior
       myList.addToFront("not.");
       myList.addToFront("or");
       myList.addToRear("is");
       myList.addToRear("try.");
       myList.addAfterItem("is", "no");
       myList.addBeforeItem("is", "There");
       myList.addToFront("Do");
       myList.addAfterItem("or", "do");
      
       myList.print("Original list");
       myList.printSorted("Sorted Original List");
          
       sop("\nFront is " + myList.getFront());
       sop("Rear is " + myList.getRear());
       sop("Count is " + myList.askCount());
       sop("Is There present? " + myList.isPresent("There"));
       sop("Is Dog present? " + myList.isPresent("Dog"));
  
       myList.addToFront("junk");
       myList.addToRear("morejunk");
       myList.addAfterItem("or", "moremorejunk");
      
       myList.print("List with junk");
       sop("Count is " + myList.askCount());
      
       myList.removeFront();
       myList.removeRear();
       myList.removeItem("moremorejunk");
       myList.print("List with junk removed");
       sop("Count is " + myList.askCount());
       sop("");
      
       // Cause List Full message
       for(int ii = 0; ii < 10; ++ii)
       {
           myList.addToFront(DUMMY);
       }
      
       myList.addToRear(DUMMY);
       myList.addBeforeItem("no", DUMMY);
       myList.addAfterItem("There", DUMMY);
      
       myList.print("After filling List");
       sop("Count is " + myList.askCount());
      
       while(myList.isPresent(DUMMY)) myList.removeItem(DUMMY);
      
       myList.print("After removing " + DUMMY );
       sop("Count is " + myList.askCount());
   }
  
   private static void sop(String s)
   {
       System.out.println(s);
   }
      
   private static final String DUMMY = "dummy";
}

Corporation W owns 100% of the common stock of Corporation Z with a basis of $300. Z owns a rental building (its only asset) with a gross fair market value of $3,000, subject to a non-recourse mortgage of $1,200. Z’s adjusted basis for this building is $900. Z has $600 of E&P. Z is on the accrual method of accounting and reports on the calendar year. Z and W do not report on a consolidated basis. Z distributes the building to W in complete liquidation and W sells the building to Corporation V for $1,800 cash, subject to the debt. Same facts as above, except that W sells the Z stock to V for $1,800 cash instead of selling the building following a liquidation.

a. V should make a Section 338 election as a normal procedure in order to obtain a cost basis in the Z assets.

b. V should make a Section 338 election because of the tax under 338 on the hypothetical sale unless Z has losses.

c. V should make a 338 election if it is an S Corporation.

d. None of the above.

Falling Bodies. In the simplest model of the motion of a falling body, the velocity increases in proportion to the increase in the time that the body has been falling. If the velocity is given in feet per second, measurements show the constant of proportionality is approximately

32. a) A ball is falling at a velocity of 40 feet/sec after 1 second. How fast is it falling after 3 seconds?

b) Express the change in the ball’s velocity ∆v as a linear function of the change in time ∆t.

c) Express v as a linear function of t. The model can be expanded to keep track of the distance that the body has fallen. If the distance d is measured in feet, the units of d ′ are feet per second; in fact, d ′ = v. So the model describing the motion of the body is given by the rate equations d ′ = v feet per second; v ′ = 32 feet per second per second.

d) At what rate is the distance increasing after 1 second? After 2 seconds? After 3 seconds?

e) Is d a linear function of t? Explain your answer.

A researcher is interested in determining if the more than two thirds of students would support making the Tuesday before Thanksgiving a holiday. The researcher asks 1,000 random selected students if they would support making the Tuesday before Thanksgiving a holiday. Seven hundred students said that they would support the extra holiday.

Define the parameter.

a. p = the population proportion of UF students who would support making the Tuesday before Thanksgiving break a holiday.

b. phat = the sample proportion of 700 UF students who would support making the Tuesday before Thanksgiving break a holiday.

c. phat = the population proportion of UF students who would support making the Tuesday before Thanksgiving break a holiday.

d. p = the population proportion of 700 UF students who would support making the Tuesday before Thanksgiving break a holiday.