Exercise 8 - Estimate the Posterior Distribution
The CLT tells us that our estimate of the spread \(\hat{d}\) has a normal distribution with expected value \(d\) and standard deviation \(\sigma\), which we calculated in a previous exercise.
Use the formulas for the posterior distribution to calculate the expected value of the posterior distribution if we set \(\mu = 0\) and \(\tau = 0.01\).
This exercise is part of the course
HarvardX Data Science Module 4 - Inference and Modeling
Exercise instructions
- Define \(\mu\) and \(\tau\)
- Identify which elements stored in the object
results
represent \(\sigma\) and \(Y\) - Estimate
B
using \(\sigma\) and \(\tau\) - Estimate the posterior distribution using
B
, \(\mu\), and \(Y\)
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# The results` object has already been loaded. Examine the values stored: `avg` and `se` of the spread
results
# Define `mu` and `tau`
mu <- 0
tau <- 0.01
# Define a variable called `sigma` that contains the standard error in the object `results`
# Define a variable called `Y` that contains the average in the object `results`
# Define a variable `B` using `sigma` and `tau`. Print this value to the console.
# Calculate the expected value of the posterior distribution