New Functions in Week 10

vcov

{stats}

Extract the variance-covariance matrix from a fitted model

theme_minimal

{GGPLOT2}

A minimalistic theme with no background annotations

vcovHC

{sandwich}

Heteroscedasticity-consistent estimation of the covariance matrix of the coefficient estimates

max

{base}

Get maximum of a vector

bptest

{lmtest}

Breusch-Pagan Test for Homoscedasticity

abline

{graphics}

Add a straight line to a plot (by intercept/slope, or horizontal/vertical)

DescTools

{DescTools}

A package of miscellaneous functions for descriptive statistics and basic data analysis

knit_hooks

{knitr}

Get or set knitr hook functions for customising output

vif

{car}

Calculate Variance Inflation Factor

coeftest

{lmtest}

Inference for Estimated Coefficients

diag

{base}

Extract or construct diagonal elements or matrices

poly

{stats}

Compute orthogonal polynomials (used for polynomial regression)

plot

{graphics}

Generic function from base R to produce a plot

nobs

{stats}

Return the number of observations in a model object

resid

{stats}

Extracts model residuals from objects returned by modeling functions

set.seed

{base}

Initialise a pseudorandom number generator.

pchisq

{stats}

Cumulative distribution function for chi-squared distribution

sample_frac

{dplyr}

Sample a fraction of observations from a data frame

stat_smooth

{GGPLOT2}

Add a smoothed conditional mean (the stat underlying geom_smooth)

expression

{base}

Used in plots to add symbols to axes

resettest

{lmtest}

Ramsey’s RESET test for functional form of a regression model

hatvalues

{stats}

Extract leverage (hat) values from a fitted model

The end!