Code to accompany RTutorial_160930.pdf

RTutorial.R

##  RTutorial.R
##  Richard Blissett (rsl.bliss@gmail.com)
##  Code to accompany RTutorial_160930.pdf

###########################################################
# Set up environment
###########################################################

# Clear environment
rm(list=ls())

# Load packages
library(haven)

# Set working directory
setwd("~/Dropbox/Teaching/RTutorial")

# Read in data
api <- read_dta("apidata_2012_so.dta")

###########################################################
# Accessing and manipulating variables
###########################################################

# See list of variable names
names(api)

# Get summary statistics
summary(api$cst28_engl)

# Create new variable
api$total <- api$cst28_engl + api$cst28_math
# Show new list of variable names
names(api)

# Drop a variable
api$total <- NULL
# Show new list of variable names
names(api)

###########################################################
# Data analysis
###########################################################

# Store summary information in an object
msum <- summary(api$cst28_engl)

# Show full summary
msum
# Get first item in list by index
msum[1]
# Get first item in list by name
msum["Min."]

# Show frequency for categorical variable
table(api$districttype)

# Run the model
model1 <- lm(cst28_engl ~ cst28_math + pctfrpl, data=api)

# See abbreviated results
model1
# See more detailed results
summary(model1)

# See attributes of model1 object
attributes(model1)

# See attributes of summary of model1 object
attributes(summary(model1))
# Pull out just coefficient information
summary(model1)$coefficients