bptest
{lmtest}
Breusch-Pagan Test for Homoscedasticity
filter
{dplyr}
Filter out rows of a data frame according to logical vector
rm
{base}
Remove objects
names
{base}
Retrieve names of a list/vector
attach
{base}
Attach Set of R Objects to Search Path
t.test
{stats}
Performs one and two sample t-tests on vectors of data.
nobs
{gdata}
Compute the number of non-missing observations
pchisq
{stats}
Gives the distribution function of the chi-squared distribution
set.seed
{base}
Initialise a pseudorandom number generator.
vif
{car}
Calculate Variance Inflation Factor
sample_frac
{dplyr}
Sample a fraction of observations from a data frame
cut
{base}
Convert Numeric to Factor
library
{base}
Load an R package
lm
{base}
Fit a linear model
c
{base}
Combine values/vectors into a vector
vcovHC
{sandwich}
Heteroscedasticity-consistent estimation of the covariance matrix of the coefficient estimates
coeftest
{lmtest}
Inference for Estimated Coefficients
mutate
{dplyr}
Modify/create a column in a data frame
select
{dplyr}
Select columns from a tibble/data frame
summary
{base}
Obtain summary statistics or detailed regression output
resid
{stats}
Extracts model residuals from objects returned by modeling functions
read.csv
{utils}
Read a csv file to data frame. Specify stringsAsFactors = FALSE to keep all string columns as characters
setwd
{base}
Set Working Directory
ls
{base}
Return a vector of character strings giving the names of the objects in the specified environment
leveneTest
{car}
Computes Levene’s test for homogeneity of variance across groups.
The end!