Inferential Statistics

BUS708 Statistics and Data Analysis

Inferential Statistics Report Assignment 2 (Assessment 4) – Individual Word Report – Trimester 2, 2020

1 OVERVIEW OF THE ASSIGNMENT

This assignment will test your skill to present and summarise data as well as to make basic statistical

inferences in a business context. You will use the results and any feedback given in Assignment 1

(Assessment 3, Excel Report) and produce a single report in a word document. You will need to

construct interval estimates, perform suitable hypothesis tests and regression analysis, and make

conclusion and suggestion for management action.

Your report should be written in a word document and should be submitted to Turnitin following the

requirement explained below.

2 TASK DESCRIPTION

There are two datasets involved in this assignment: Dataset 1 and Dataset 2, which are the same

datasets used in Assignment 1 (Excel Report). Please refer to Assignment 1 Description for the

details about these datasets. All data processing and calculation should be performed in Excel or

Statkey (http://www.lock5stat.com/StatKey), hence you should not use a statistical table to find

critical value or p-value. Specific instruction as to which computer tools should be used for each

section will be given during tutorials.

Your tasks are to answer the following research questions given in Section 2 to Section 6 below using

dataset 1 or dataset 2 as indicated in each section. To answer each question, you will need to first

present the relevant numerical summary (summary statistics) and graphical display and perform

suitable statistical analysis to make inferences and to provide a conclusion.

Your tasks are described below.

1. Section 1: Introduction

Provide a brief and clear introduction about the report (e.g. the objective of the

report, the datasets involved, etc.). Find 1-3 articles (minimum one article, maximum

three articles) which are relevant to any of the research questions (given in Section 2

– Section 6) and write a proper literature review. Your literature review should include

in-text citation and you will need to add a reference list at the end of your report.

2. Section 2: Did around 25% of taxpayers in 2013-2014 self-prepare their tax return?

Using Dataset 1, first provide both numerical summary and graphical display that

easily shows the proportion of each lodgement method.

Then, construct a 95% confidence interval of the population proportion of Self-

preparer lodgement method.

Finally, answer the research question using the confidence interval.

3. Section 3: Is the average salary of taxpayers in 2013-2014 less than $45,000?

Using Dataset 1, first describe the salary amount distribution of Australian taxpayers

in 2013-2014. You need to provide numerical summary (sample size, mean, standard

deviation and median) as well as graphical display which shows any outliers.

Then perform a suitable hypothesis test to answer the research question above at

5% level of significance.

4. Section 4: For the total income between 75000 – 80000, is there a difference in the total

deduction between different lodgement method?

Using Dataset 1, , first filter the total income to include only the income between

$75,000 to $80,000 (inclusive). Then provide the numerical summary for the total

deduction grouped by different lodgement method. You also need to provide

graphical display which shows any outliers.

Then, perform a suitable hypothesis test to answer the research question above.

Use a 5% significance level.

5. Section 5: Is there any relationship between total income amount and total deduction

amount for self-preparer?

Using Dataset 1, first filter the data to include only self-prepare lodgement method,

then describe the relationship between total income amount and total deduction

amount using a suitable graph.

Then, perform a regression analysis and provide the numerical summary.

Finally, interpret the correlation coefficient, the coefficient of determination and the

relevant p-values and use them to answer the research question.

6. Section 6: Is there a relationship between the gender of international students and

whether they would use a tax agent?

Using Dataset 2, describe the relationship between the gender of international

students and whether they would use a tax agent. You need to provide both

numerical summary and graphical display.

Then, perform a suitable hypothesis test to answer the research question above.

Use a 5% significance level.

7. Section 7: Conclusion

Write a summary of all the findings in the previous sections and then write

concluding statements that would benefit a stake holder (e.g. tax agents, tax payers)

to take management action.

Finally, suggest further research by discussing an interesting topic or a research

question that can be further explored related to the datasets and/or the findings.

3 SUBMISSION REQUIREMENT

Deadline to submit the report: the end of Week 11 – Sunday, 27th September 2020, 23:59 (11:59pm)

You need to submit a word document file to Turnitin which shows all computer outputs (numerical

summary & graphs) and discussion. You do not need to submit the dataset. You do not need to

submit the Excel file.

4 MARKING CRITERIA

Students are advised to read the marking rubric provided on Moodle as well as detailed marking

criteria based on this rubric.

5 DEDUCTION, LATE SUBMISSION AND EXTENSION

Late submission penalty: - 5% of the total available marks per calendar day unless an extension is

approved. This means 0.75 marks (out of 15 marks) per day.

For extension application procedure, please refer to Section 3.3 of the Subject Outline. Please do

NOT email the lecturer or tutor to seek an extension, you need to follow the procedure described in

the Subject Outline. The form to apply for an extension can be found on Moodle

(http://koi.edu.au/wp/policies-forms-2/)

6 PLAGIARISM

Please read Section 3.4 Plagiarism and Referencing, from the Subject Outline. Below is part of the

statement:

“Students plagiarising run the risk of severe penalties ranging from a reduction through to 0 marks for a first offence for a single assessment task, to exclusion from KOI in the most serious repeat cases. Exclusion has

serious visa implications.”

“Authorship is also an issue under Plagiarism – KOI expects students to submit their own original work in both assessment and exams, or the original work of their group in the case of a group project. All students agree to a statement of authorship when submitting assessments online via Moodle, stating that the work submitted is their own original work. The following are examples of academic misconduct and can attract severe penalties:

• Handing in work created by someone else (without acknowledgement), whether copied from another student, written by someone else, or from any published or electronic source, is fraud, and falls under the general Plagiarism guidelines.

• Students who willingly allow another student to copy their work in any assessment may be considered

to assisting in copying/cheating, and similar penalties may be applied. ”