BUS1BAN Project 2: Market Share & Mobile Phone Usage at La Trobe Uni

This research project investigates mobile phone usage and market share among students at La Trobe University, focusing on inferential statistics. It includes point estimates and confidence intervals for student demographics (gender, phone brand) and average monthly earnings. Hypothesis testing is conducted to compare iPhone market share at La Trobe with US market data. The project explores the impact of price discounts on Samsung Galaxy preference versus iPhones, employing statistical measures and linear regression analysis to understand the relationship. The summary discusses the differences between confidence intervals for proportions and means, the conditions for hypothesis testing, and the interpretation of regression analysis results, including intercept, slope, and R-squared values.

Cover Page
Research Project-2: BUS1BAN
Teacher’s Name
Workshop Details
(Time, day, room)
Students ID Number Students Name Student contribution*
(%)
e.g. 50% means the
student will receive 50%
of the marks awarded
Students Signature
*All group members are to exert an equal amount of effort on all questions of the assignment.
Students should not divide sections. If a student has contributed to only some sections, the
contribution of the student should be equal to the marks it carries. A student with less than
100% contribution will receive marks proportional to their contribution.
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An insight into market share and usage of
mobile phones by students at La Trobe University
Note: Students would continue to be the part of the same group as were
for research project-1 and would be utilising the data from the same
random sample that they have already submitted earlier.
Inferential Statistics
1. Point Estimate and Confidence Interval: (20 marks)
A. Suppose you randomly select a student from BUS1BAN class, how likely
is it that the student selected will be: (5 marks)
 A female;
 A male;
 An IPhone user;
 A Samsung Galaxy user.
Proportion ( ^p)
Female Students 0.52
Male Students 0.48
IPhone Users 0.753
Other Smart Phone Users 0.093
B. Estimate 95% confidence interval of the proportion of female students and the
proportion of Other Smart Phone User. Show the confidence intervals
graphically, and interpret your results. (You must show the formula and show
working by putting values in the formula accordingly): (5 marks)
i.Female Students (2.5 marks)
Lower limit = 0.44
Upper limit = 0.60
This results show that 95% of the times the proportion of females will always
be between 0.44 and 0.60
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ii.Other Smart Phone Users (2.5 marks)
Lower limit = 0.047
Upper limit = 0.139
This results show that 95% of the times the proportion of those who use
other smartphones will always be between 0.047 and 0.139
Proportion of females Proportion of other smartphone users
0
0.1
0.2
0.3
0.4
0.5
0.6
95% C.I for proportion
Figure 1
C. What are the average monthly earnings of male and female students at
La Trobe? (5 mark)
Female Male
Average Monthly
Earnings ($)
1004.47 1227.76
D. Provide 95% confidence interval of the average monthly earnings for each
gender, show the confidence intervals graphically, and interpret your answer.
(5 marks)
i.Female (2.5 marks)
Lower limit 829.02
Upper limit 1179.92
ii.Male. (2.5 marks)
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Lower limit 1006.07
Upper limit 1449.45
2. Hypothesis Testing: (20 marks)
A US market survey shows that the market share of iPhone is more than 40% of the US
market. Is it true for La Trobe students as well? Use your sample data to test this claim at
5% level of significance and interpret your answer. (Clearly label and follow the 5 steps of
hypothesis testing procedure as outlined on the formula sheet and you must show the
formula and show working by putting values in the formula accordingly).
3. The effect of price on preference [Samsung versus Apple]: (50 marks)
A. IPhone and Samsung are two important players in the smartphone market
who compete against each other. Samsung’s phones are generally sold
cheaper than Apple’s smartphones. Complete the following table using the
survey data responses (5 marks)
Discount offered
on Samsung
Galaxy
Proportion of students who said they would buy the
latest Samsung Galaxy instead of the latest iPhone if
the price of Samsung Galaxy were discounted.
x Y(f) Y(m)
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
50%
B. Produce an appropriate graph to explain the relationship between discount
offered by Samsung on its latest Galaxy vis-à-vis the latest iPhone and change in
potential market share of Samsung Galaxy by using data in part 3-A. (5 marks)
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C. Using excel provide the following statistical measures to explain the
relationship between discount offered by Samsung on its latest Galaxy vis-à-vis
the latest iPhone and change in potential market share of Samsung Galaxy by
using data in part 3-A. (5 marks)
D. Using data in part (3-A), perform linear regression using excel and follow the
instructions below: (35 marks)
i. Paste the excel output of linear regression hereunder. (3 marks)
ii. What type of linear regression is it and why? (3 marks)
(Hint: Simple or Multiple)
iii. Report the values of slope coefficient and intercept? (4 marks)
iv. Using information from (i) or (iii) above write down the linear regression
equation. (Note similarity between linear regression equation with the
least square line in 3-C). (3 marks)
v. Interpret Intercept: (3 marks)
vi. Interpret Slope Coefficient: (3 marks)
vii. Interpret Coefficient of determination: (3 marks)
viii. What is the relationship between Coefficient of Correlation and Coefficient
of Determination? Compute Coefficient of Correlation by using Coefficient
of Determination (Show working): (3 marks)
ix. Perform hypothesis testing to test slope for linear relationship by using t-
statistics in the excel output. (Clearly label and follow the 5 steps of
hypothesis testing procedure as outlined on the formula sheet and you
must show the formula and show working by putting values in the formula
accordingly). (10 marks)
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4. Summary and discussion (10 marks):
Provide a summary of the above analysis by covering the following points:
 Compare the confidence interval estimates of part 1-B and 1-D in terms of conditions used
to employ specific formulae. Why does part 1-B differ from 1-D (conceptually not
numbers)? (4 to 6 lines – 3 marks)
There is a great difference between the two parts. This is because one is confidence interval for
proportion while the other one is confidence interval for the mean. The mean refers to a
measure of centre and takes into account the entire sample while proportion only takes into
account the points of interest. That is why the two intervals are different and hence using
different formulas.
 Summarise the hypothesis testing in part 2 (conceptually not numbers) by explaining the
conditions used to employ specific formula. (4 to 6 lines – 3 marks)
 Summarise regression analysis starting with differentiating between simple and multiple
regression, discussing relationship between the two variables by explaining intercept,
slope and R square. (10 to 12 lines – 4 marks)
Please use Harvard Style of Referencing
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