# STAT7030 ANU Generalised Linear Models

Question 1. [48 Marks]. The file Doctor Data, available on the course Wattle page in theDatasets section, is concerned with the number of deaths by heart disease in a sample of
doctors from different age groups and with different smoking status (smoker/non-smoker).
Further details are given below.
Column 1 Observation number – [Variable V1=1 to 10]
Column 2 Age – [Variable V2= 1,2,3,4,5] {1 = 35-44 years; 2 = 45-54 years;
3 = 55-64 years; 4 = 65-74 years; 5 = 75-84 years}.
Column 3 Deaths – [Varaible V3 = Number of Deaths] {Count Variable}.
Column 4 Person-Years at Risk – [Variable V4 = Aggregate years] {Count Variable}.
Column 5 Smoker – [Variable V5 = 1,2] { Factor: 1 = Smoker; 2 = Non-Smoker}.
Further comment: do not forget to declare variable V 5 as a factor.
(a) Fit a suitable set of Poission regression models to the data and select what you think is
the best model, using AIC to inform your selection. Please bear the following points
in mind:
• Treat log(V 4) as a covariate (as opposed to an offset) throughout part (a).
• Although variable V 2 could be treated as a factor, it is suggested that you treat
it as a numerical variable. If treated as a factor, Age will use up too many
parameters relative to the sample size. Also, consider the covariate V 2 ∗ V 2.
• Investigate interactions as well as main effects.
• Present the AIC values in a suitable table.
• Use suitable residual plots and other diagnostics to investigate the goodness of
fit of the model you select.
• In part (a) and in part (b) below, take the scale parameter φ to be 1.
[12 marks]
(b) Focusing on the model you selected in part (a), perform a change of deviance test to
assess whether it would be better to treat log(V 4) as an offset or as a covariate.
[6 marks]
(c) Repeat parts (a) and (b) using negative binomial regression models with a log link.
Comment on (i) similarities and (ii) differences in your results for part (c), compared
with parts (a) and (b).
[18 marks]
2
(d) Returning to the best Poisson regression model that you identified in part (a), estimate
the scale parameter φ and provide a Wald test of the null hypothesis that φ = 1,
presenting your answer in the form of a p-value. As part of your answer to part (d)
you should present the R code that you used.
[12 marks]
3
1 1 32 52407 1
2 2 104 43248 1
3 3 206 28612 1
4 4 186 12663 1
5 5 102 5317 1
6 1 2 18790 2
7 2 12 10673 2
8 3 28 5710 2
9 4 28 2585 2
10 5 31 1462 2

Don't use plagiarized sources. Get Your Custom Essay on
STAT7030 ANU Generalised Linear Models
Just from \$13/Page
Calculate your paper price
Pages (550 words)
Approximate price: -

Why Work with Us

Top Quality and Well-Researched Papers

We always make sure that writers follow all your instructions precisely. You can choose your academic level: high school, college/university or professional, and we will assign a writer who has a respective degree.

Professional and Experienced Academic Writers

We have a team of professional writers with experience in academic and business writing. Many are native speakers and able to perform any task for which you need help.

Free Unlimited Revisions

If you think we missed something, send your order for a free revision. You have 10 days to submit the order for review after you have received the final document. You can do this yourself after logging into your personal account or by contacting our support.

Prompt Delivery and 100% Money-Back-Guarantee

All papers are always delivered on time. In case we need more time to master your paper, we may contact you regarding the deadline extension. In case you cannot provide us with more time, a 100% refund is guaranteed.

Original & Confidential

We use several writing tools checks to ensure that all documents you receive are free from plagiarism. Our editors carefully review all quotations in the text. We also promise maximum confidentiality in all of our services.

Our support agents are available 24 hours a day 7 days a week and committed to providing you with the best customer experience. Get in touch whenever you need any assistance.

Try it now!

## Calculate the price of your order

Total price:
\$0.00

How it works?

Follow these simple steps to get your paper done

Fill in the order form and provide all details of your assignment.

Proceed with the payment

Choose the payment system that suits you most.

Receive the final file

Once your paper is ready, we will email it to you.

Our Services

No need to work on your paper at night. Sleep tight, we will cover your back. We offer all kinds of writing services.

## Essay Writing Service

No matter what kind of academic paper you need and how urgent you need it, you are welcome to choose your academic level and the type of your paper at an affordable price. We take care of all your paper needs and give a 24/7 customer care support system.