Week 7 - Basic Modelling Flashcards
1
Q
Why bother with models?
A
They allow us to understand how variables are related, the strength of the relationship as well as the direction of the relationship.
Allows us to predict the outcome of interest.
2
Q
Is correlation a good measure of two variables?
A
Can be, can also be spurious.
3
Q
What are model families?
A
Model families describe the relationship between an outcome (Y) and an input (X). E.g. A class of polynomials.
4
Q
What are the measures of distance? Explain how they work
A
OLS, least absolute deviations
5
Q
How does grid search work?
A
Has a grid of values, beta0 and b1. Evaluate f(beta0, beta1) find beta0 and beta1 that makes f(beta0, beta1) smallest.
6
Q
What does the optim function do?
A
Allows you to optimise user supplied functions.
