How Do We Construct A Frequency Distribution Table Using R? Part 1

We will use States Visited, (StatesV) variables included in the first-day class survey, Sur1.

1. Upload Sur1.csv data set from your desktop to R

Sur1 <-read.csv("~/Desktop/Sur1.csv")

NOTE: In case you did not save Sur1.csv file correctly to your desktop, execute the following code
Sur1 <-read.csv(read.csv(file.choose(),header = TRUE))

1. Examinne the strucure of Sur1 data set

str(Sur1)

## 'data.frame':    20 obs. of  6 variables:
##  $ SEX      : Factor w/ 2 levels "Female","Male": 1 1 1 1 2 2 2 1 1 1 ...
##  $ POLITICS : Factor w/ 3 levels "Conservative",..: 3 3 3 3 3 3 2 2 1 3 ...
##  $ NSiblings: int  4 4 2 2 2 4 5 4 4 1 ...
##  $ StatesV  : int  5 11 6 3 7 3 4 4 6 3 ...
##  $ ShoeS    : num  6 9 8 7.5 13 10.5 9 8 6 8.5 ...
##  $ UsedExcel: int  2 2 2 1 1 3 3 2 2 1 ...

1. View first six row of the data in spreadsheet format

head(Sur1, 6)

##      SEX POLITICS NSiblings StatesV ShoeS UsedExcel
## 1 Female Moderate         4       5   6.0         2
## 2 Female Moderate         4      11   9.0         2
## 3 Female Moderate         2       6   8.0         2
## 4 Female Moderate         2       3   7.5         1
## 5   Male Moderate         2       7  13.0         1
## 6   Male Moderate         4       3  10.5         3

1. Attach Sur1 to R in order to work with data variables without using $ symbol (remember to detach(Sur1) after completion of analysis)

attach(Sur1)

1. Summarize StatesV variable

summary(StatesV)

##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##    3.00    4.00    6.00    7.15    9.50   18.00

1. Construct a frequency distribution table of States Visited using breaks to list class limits

breaks <-seq(0,18, by=3)

1. Group StatesV variable data into bins

StatesV.cut <-cut(StatesV,breaks)

1. Construct frequency table for StatesV variable in horizontal display

 table(StatesV.cut)

## StatesV.cut
##   (0,3]   (3,6]   (6,9]  (9,12] (12,15] (15,18] 
##       3       8       4       3       1       1

1. Transform this table to 2-column display

transform(table(StatesV.cut))

##   StatesV.cut Freq
## 1       (0,3]    3
## 2       (3,6]    8
## 3       (6,9]    4
## 4      (9,12]    3
## 5     (12,15]    1
## 6     (15,18]    1

1. Construct a histogram of the frequency distribution of StatesV variable

hist(StatesV,breaks,col="red",border = "blue",xlab="Number of States Visited",xlim = c(0,21),ylab="Frequency",main="Distribution of States Visited by Mat150-1701 Students")