HW2.R

# House Keeping:
rm(list = ls())
setwd("/Users/bmishra/Dropbox/OSU/PhD/Fall 2021/STAT5193 SAS R/R/Assignments/Homework 2")

# txtsent = read.table(file = "clipboard", header = TRUE)[[4]]
# txtrec = read.table(file = "clipboard", header = TRUE)[[5]]
# introvert = read.table(file = "clipboard", header = TRUE)[[9]]
# snapchat =  read.table(file = "clipboard", header = TRUE)[[8]]

# Assignment 2:
# Q1 (a): 
txtsent = c(1, 10, 150, 18, 30, 100, 20, 100, 150, 
            75, 75, 50, 25, 100, 30, 5, 20, 200, 
            50, 10, 100, 100, 30, 10, 30, 10, 9, 
            100,11, 2, 10, 5, 10, 5, 25)
txtrec = c(1, 15, 150, 28, 30, 75, 20, 100, 150, 
           75, 75, 50, 30, 100, 30, 5, 40, 200, 
           50, 10, 100, 100, 30, 10, 30, 20, 3, 
           200, 15, 3, 10, 5, 15, 5, 25)
introvert = c(8, 8, 1, 4, 4, 6, 5, 6, 3, 5, 5,
              3.5, 8, 5, 5, 8, 3, 3, 8, 3, 1, 
              4, 7, 5, 7, 5, 5, 6, 3, 4, 3, 2, 6, 3, 7)

# Q1(b):
txtrec[c(1, 5)]

## [1]  1 30

txtsent[c(1, 5)]

## [1]  1 30

introvert[c(1, 5)]

## [1] 8 4

#Q1(c):
mean(introvert)

## [1] 4.842857

sd(introvert)

## [1] 1.995478

# Q1(d):
mode(txtsent)

## [1] "numeric"

#Q1(e):
Snapchat = c("Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "N",
             "Y", "Y", "N", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "N", "N", "Y", 
             "Y", "Y", "N", "N", "N", "N", "N", "N", "N")
Snapchat[c(1:2)]

## [1] "Y" "Y"

#Q1 (f):
mode(Snapchat)

## [1] "character"

# We have text or character as elements of this vector (snapchat). Thus we cannot calculate the mean of snapchat.

# Q2:
# Q2(a):
SM = matrix(c(txtrec, txtsent, introvert), nrow = 35, ncol = 3)
colnames(SM) = c("TxtRec", "TxtSent", "Introvert")
rownames(SM) = c(1:35)
SM[1:4,]

##   TxtRec TxtSent Introvert
## 1      1       1         8
## 2     15      10         8
## 3    150     150         1
## 4     28      18         4

# Q2(b):
class(SM)

## [1] "matrix"

dim(SM)

## [1] 35  3

# Q2(c):
median(txtsent - txtrec)

## [1] 0

mean(txtsent - txtrec)

## [1] -3.685714

#Q2(d):
SM2 = cbind(SM, Snapchat)

# Q2(e):
summary(SM)

##      TxtRec          TxtSent         Introvert    
##  Min.   :  1.00   Min.   :  1.00   Min.   :1.000  
##  1st Qu.: 12.50   1st Qu.: 10.00   1st Qu.:3.000  
##  Median : 30.00   Median : 25.00   Median :5.000  
##  Mean   : 51.57   Mean   : 47.89   Mean   :4.843  
##  3rd Qu.: 75.00   3rd Qu.: 87.50   3rd Qu.:6.000  
##  Max.   :200.00   Max.   :200.00   Max.   :8.000

summary(SM2)

##      TxtRec      TxtSent     Introvert Snapchat
##  30     : 5   10     : 6   5      :8   N:11    
##  100    : 4   100    : 6   3      :7   Y:24    
##  10     : 3   30     : 4   8      :5           
##  15     : 3   5      : 3   4      :4           
##  5      : 3   150    : 2   6      :4           
##  75     : 3   20     : 2   7      :3           
##  (Other):14   (Other):12   (Other):4

# summary(SM) is creating summary for values in each variable in the matrix.
# summary(SM2) is creating summary for each variable in the matrix but not values.

# Q3:
SM.Array = array(data = SM, dim = c(35, 3), 
                 dimnames = list(1:35, c("TxtRec", "TxtSent", "Introvert")))
SM.Array[c(1, 35),]

##    TxtRec TxtSent Introvert
## 1       1       1         8
## 35     25      25         7

save.image("HW2.RData")
load("HW2.RData")