How do I do this in R Studio?

1 Students who performed poorly on a City of New York Skills Assessment Test were enrolled in a summer math program. Scores of 10 students before and after the summer program were recorded.

They were:

Before = 18,18,21,18,18,20,23,23,21,17

After = 24,25,33,29,33,36,34,36,34,27

(Scores for individual students are in the same order in each list.) Did the NYC summer math program improve student performance significantly?

8. How many points did student scores improve on average? (hint: consult the output from question 1; it’s OK to simply write this answer – it did come from R output.)

9. What is the 95% confidence interval for the parameter of average score improvement? (hint: consult the output from question 1; it’s OK to simply write this answer – it did come from R output.)

A researcher hypothesizes that arousal levels will be affected by meditation. The sample participates in formal meditation classes for 3 weeks, before and after which arousal is measured.

Subject                      BEFORE MEDITATION                               AFTER MEDITATION

1                                                  72                                                                           91

2                                                  162                                                                       155

3                                                  145                                                                       152

4                                                  183                                                                       190

5                                                  123                                                                       134

6                                                  167                                                                       157

7                                                  76                                                                           99

8                                                  112                                                                       104

9                                                  124                                                                       143

10                                               137                                                                       156

6. Please analyze the data using the appropriate hypothesis test on SPSS and cut and paste your SPSS results here:

7. Based on your SPSS results, do you reject or fail to reject the null?

_____________________________________________

8. Please write the “statistical statement” for your SPSS results:

9. Please write your results in a “literature” or “research study” format:

Matwirth corporation has instituted a new disciplinary policy for employees who fail a random drug test. The personnel office wishes to test to see if there is a difference in employee behavior based on the new policy. The records of 500 employee drug tests from before the new policy were randomly selected and 500 drug test results from after the new policy were also randomly selected. In the sample from before the new policy, 1.80% tested positive, while 1.40% in the sample from after the new policy tested positive.

            For the hypotheses,

            H₀: p₁ = p₂   and   H_A: p₁ > p₂,

            what is the p-value and the conclusion of this test at the 0.1 level of significance?

            8. Construct a 99% confidence interval for the population mean for a sample of size 20 with mean 5.01 and standard deviation 2.21.

WITH EXPLAINATION OF WORK

A study was conducted to test the effectiveness of a software patch in reducing system failures over a six-month period. Results for randomly selected installations are shown in the table below. The "before" value is matched to an "after" value, and the differences are calculated. The differences have a normal distribution. Test at the 1% significance level. Installation A B C D E F G H

Before 3 6 4 2 5 8 2 6

After 1 5 2 0 1 0 2 2

A) State the null and alternative hypotheses.

H₀: μ_d < 0
H_a: μ_d ≥ 0

H₀: μ_d = 0
H_a: μ_d ≠ 0    

H₀: μ_d ≤ 0
H_a: μ_d > 0

H₀: μ_d ≠ 0
H_a: μ_d = 0

H₀: μ_d ≥ 0
H_a: μ_d < 0

B) Draw the graph of the p-value.

Hannah coaches a youth soccer team . Tomorrow night, they have a game. Suppose there is a 43% chance that her team will lose. Regardless of whether her team loses, Hannah figures there is a 58% chance that a parent will complain about something to her after the game. From previous seasons, Hannah knows that the probability that her team loses and a parent complains is 35%.  (Hint: Organize and label the given information first before starting. Write out the probability statement for each question before calculating anything.)

(Round all probabilities to four decimals)

1. Suppose Hannah’s soccer team loses. What is the probability that a parent complains?

2. If a parent complains after the game, what is the probability that Hannah’s team lost?

3. What is the probability that Hannah’s team will win tomorrow night?

4. Suppose Hannah’s soccer team loses. What is the probability that a parent does not complain?

10. Locomotive Corporation is planning to repurchase part of its common stock by issuing corporate debt. As a result, the firm’s debt–equity ratio is expected to rise from 30 percent to 45 percent. The firm currently has $10 million worth of debt outstanding. The cost of this debt is 6.5 percent per year. The firm expects to have an EBIT of $3 million per year in perpetuity and pays no taxes.

a. What is the market value of the firm before and after the repurchase announcement? (0.75 point)

b. What is the expected return on the firm’s equity before the announcement of the stock repurchase plan? (0.75 point)

c. What is the expected return on the equity of an otherwise identical all-equity firm? (0.75 point)

d. What is the expected return on the firm’s equity after the announcement of the stock repurchase plan? (0.75 point)

A dietitian wishes to see if a person’s cholesterol level will change if their diet is supplemented by a certain mineral. Six randomly selected subjects had their cholesterol level measured before and then took the mineral supplement for 5 weeks. The same six subjects had their cholesterol level measured again after the 5-week supplement. The results are shown below.  Assume the two population distributions are normal and the subjects were selected independently.

Can it be concluded that the cholesterol level has changed at 5% significance level?    

Question:Which of the following is the correct calculator command to use?

2-SamTTest

ANOVA

2-SampZint

Z-Test

Z-Interval

T-Test

T-Interval

2-SampTInt

2-SampZTest

At the end of 2021, Marin Co. has accounts receivable of $754,500 and an allowance for doubtful accounts of $23,960. On January 24, 2022, it is learned that the company’s receivable from Madonna Inc. is not collectible and therefore management authorizes a write-off of $4,624.

a)

Prepare the journal entry to record the write-off. (Credit account titles are automatically indented when amount is entered. Do not indent manually.)

(b)

What is the cash realizable value of the accounts receivable before the write-off and after the write-off?

At the end of 2016, Coronado Industries has accounts receivable of $762,000 and an allowance for doubtful accounts of $22,520. On January 24, 2017, it is learned that the company’s receivable from Madonna Inc. is not collectible and therefore management authorizes a write-off of $4,398.

(a) Prepare the journal entry to record the write-off. (Credit account titles are automatically indented when amount is entered. Do not indent manually.)

(b) What is the cash realizable value of the accounts receivable before the write-off and after the write-off?