STAT 545A Homework 2

Sep 15 2013


Contents

Introduction

In this report, I will be taking a look at the Gapminder data set provided by Jenny for our STAT 545A (2013W) class.

The purpose of this report is to practice using R Markdown to generate reports. I will take a look at the Gapminder data set and practice using the ggplot2 package to generate plots.

A First Look at the Data

We begin by reading in the tab delimited data set using the read.delim function in R.

gDat <- read.delim(file = "gapminderDataFiveYear.txt")

It is always a good idea to check the structure of the data using the str function.

str(gDat)
## 'data.frame':    1704 obs. of  6 variables:
##  $ country  : Factor w/ 142 levels "Afghanistan",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ year     : int  1952 1957 1962 1967 1972 1977 1982 1987 1992 1997 ...
##  $ pop      : num  8425333 9240934 10267083 11537966 13079460 ...
##  $ continent: Factor w/ 5 levels "Africa","Americas",..: 3 3 3 3 3 3 3 3 3 3 ...
##  $ lifeExp  : num  28.8 30.3 32 34 36.1 ...
##  $ gdpPercap: num  779 821 853 836 740 ...

We can also use the summary function to provide a summary of a given R object. In our case, since we input a data.frame object, we recieve some summary statistics of the variables inside our data set.

summary(gDat)
##         country          year           pop              continent  
##  Afghanistan:  12   Min.   :1952   Min.   :6.00e+04   Africa  :624  
##  Albania    :  12   1st Qu.:1966   1st Qu.:2.79e+06   Americas:300  
##  Algeria    :  12   Median :1980   Median :7.02e+06   Asia    :396  
##  Angola     :  12   Mean   :1980   Mean   :2.96e+07   Europe  :360  
##  Argentina  :  12   3rd Qu.:1993   3rd Qu.:1.96e+07   Oceania : 24  
##  Australia  :  12   Max.   :2007   Max.   :1.32e+09                 
##  (Other)    :1632                                                   
##     lifeExp       gdpPercap     
##  Min.   :23.6   Min.   :   241  
##  1st Qu.:48.2   1st Qu.:  1202  
##  Median :60.7   Median :  3532  
##  Mean   :59.5   Mean   :  7215  
##  3rd Qu.:70.8   3rd Qu.:  9325  
##  Max.   :82.6   Max.   :113523  
## 

Some Pretty Plots

In an attempt to learn how to make plots with the ggplot2 package, I try to recreate the first 6 of Jenny's lattice plots from the lecture 2 “Work through” exercise (Basic care and feeding of data in R).

plot of chunk unnamed-chunk-1

For the code used to generate this report, click here