Please use D2L to turn in both the PDF output and your R Markdown file.

Q1. (5 pts)

Sketch out the steps for a Gibbs sampler algorithm.

Q2. (45 pts)

Simulating data is a key step in verifying your algorithms are working correctly. This will be more apparent as we start studying sophisticated hierarchical models.

a. (5 pts)

Simulate 100 observations from a standard normal distribution and plot a histogram of your data.

b. (5 pts)

Select and state prior distributions for \(\theta\) the mean of the normal distribution and \(\sigma^2\) the variance (or alternatively you may parameterize your model using the precision term).

c. (10 pts)

Implement a Gibbs sampler to simulate from the joint posterior distribution \(p(\theta,\sigma^2|y_1, \dots, y_{100})\). Create a plot of the joint posterior distribution.

d. (10 pts)

Plot trace plots and histograms of the marginal posterior distributions for \(\theta\) and \(\sigma^2\). Include the true values on these figures. Comment on the figures.

e. (10 pts)

Use your MCMC samples to create a posterior predictive distribution. Compare the data and your posterior predictive distribution using a QQ plot qqnorm(). Comment on the figure.