# 程序代写代做代考 STA 104 Take Home Exam I, due Wednesday, Feb 3th 10:00AM on Gradescope

STA 104 Take Home Exam I, due Wednesday, Feb 3th 10:00AM on Gradescope

Read the following instructions carefully:

• You are not allowed to discuss the questions with anyone other than the instructor or TA.

• Any outside help beyond that from the instructor or TA is considered plagiarism. This including asking a tutor, your classmates (for example, comparing answers), posting the questions to homework help sites, etc. Should we believe you have sought outside help, you will be reported to the Student Judicial Affairs office.

• You are allowed to use or modify your previous functions, or the instructors functions that are posted online.

• Do not share answers, or specific values for calculations, particularly on Piazza.

• You may ask clarifying questions about code and general approach on Piazza, but do not give away any numerical answers. If you are concerned you may be giving something away, email me (canvas inbox preferred) or the TA’s directly.

• When you submit your work into Gradescope, you should match your work to each question. If not, 5% of the total score will be deducted.

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The instructor will randomly assign one question from Take Home Exam and one question from Take Home Project. The data will be sent to you via canvas inbox by Jan 29 5:00 PM. If you have not received them by the time, contact the instructor.

Take Home Exam Question 1

The data used for this question is Toys.csv, and it has a column Broken. What has been measured is how many toys a particularly agile cat breed (A Bengal Cat) “destroys” in a week. A frustrated owner believes that they have to buy over 3 toys per week in order to keep up with their cat. Assess this claim using the median.

Question 2

The data used for this question is Play.csv, with a column Return. Border collies are dogs known for their obsessive behavior, and 16 border collie owners measured how many times in a row their dogs returned a ball to the owner after it was thrown. They claim that there is a 50% change that the dogs will return the ball 12 times or more. Assess this claim using the median.

Take Home Project

Topic 1

The data is found in the file Drug.csv, with the following columns:

Column 1: Relief: The number of hours of relief provided.

Column 2: Groups: Either DrugA or DrugB.

The study was comparing the hours of pain relief for two common over-the-counter pain medications. Compare the two groups, being as specific as you can about your outcome.

Topic 2

The data is found in the file soil.csv, with the following columns:

Column 1: condition: gap (the soil was under an opening in the forest canopy), and growth (the soil was taken under heavy

tree growth).

Column 2: respiration: The amount of carbon dioxide given off by each soil core (in mol CO2g soiohr).

Soil respiration is a measure of Microbial activity in soil, which affects plant growth. Compare the two groups, being as specific as you can about your outcome.

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3. The Report Format

The project should be a short report. This means you write in full sentences, and have the following sections, while being as specific as you can about your results. There should not be any “copy and pasted” R code in this report. You must format the results you get from R.

I. Introduction. State the question you are trying to answer, why it is a question of interest (why might we be interested in the answer), and what statistical technique you are going to use. This must be a non-parametric technique.

II. Summary of your data (and only the data you are using for your topic). This should include things like plots (histograms, boxplots) including the interpretation of the plots, and summary values such as sample means and standard deviations. This is where you should justify which non-parametric technique you are using. An R handout is available online for graphing and summaries of various data types.

III. Analysis. Report back confidence intervals, test-statistics, and p-values, nulls and alternatives, etc. You may use tables here, but be sure that you organize your work. Remember to write your results in full sentences where possible.

IV. Interpretation. State your conclusion, and inference that you may draw from your corresponding tests or confidence intervals. These should all be in terms of your problem.

V. Conclusion. Summarize briefly your findings. Here you do not have to re-iterate your numeric values, but summarize all relevant conclusions.

4. Details

Your report should be the following format: i. Typed.

ii. A title page including your name (SID), email the name of the class, and the name of your instructor (me).

iii. An appendix of your R code used to produce the results. Do not include in R code in the body of your report.

For example, your work should be put together in the order:

Take Home Exam (template/worksheet provided)

Code appendix for Take Home Exam

Title Page for Take Home Project

Parts I-V for Take Home Project

Code appendix for Take Home Project

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Rubric for Take Home Project

• Presence of content (40%)

1. States statistical question of interest 2. States why it is of interest

3. States statistical technique to use

4. Summary values and graphs

5. Null/alternatives should be present or easily deducible from methods 6. Results (test statistics, confidence intervals, p-values

7. Interpretation of results

8. Conclusion with respect to the statistical questions of interest

9. R code present

• Accuracy of content (40%)

1. Data is well-portrayed by summary values/graphs

2. Technique answers the question of interest

3. Technique is appropriate given the data

4. Statistical methods are properly used (correct null/alternative, CI, p-values)

5. Correct interpretation

6. Conclusion follows from interpretation

7. Conclusion satisfactorily addresses question of interest

8. R code would generate the result

• Style of content (20%)

1. Easy to find important information

2. General style of report format is adhered to (okay if there are some deviations from I-VI format, as long as the order is logical)

3. No raw R output in body of the report

4. Graphs are clearly marked (labels, etc.)

5. Some attempt at writing clearly (full sentences, etc.)

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