Week1

Problem #1

library(IPSUR)
require(IPSUR)
require(psych)

## Loading required package: psych

require(MASS)

## Loading required package: MASS

require(car)

## Loading required package: car

## Loading required package: carData

## 
## Attaching package: 'car'

## The following object is masked from 'package:psych':
## 
##     logit

require(data.tree)

## Loading required package: data.tree

summary(iris)

##   Sepal.Length    Sepal.Width     Petal.Length    Petal.Width   
##  Min.   :4.300   Min.   :2.000   Min.   :1.000   Min.   :0.100  
##  1st Qu.:5.100   1st Qu.:2.800   1st Qu.:1.600   1st Qu.:0.300  
##  Median :5.800   Median :3.000   Median :4.350   Median :1.300  
##  Mean   :5.843   Mean   :3.057   Mean   :3.758   Mean   :1.199  
##  3rd Qu.:6.400   3rd Qu.:3.300   3rd Qu.:5.100   3rd Qu.:1.800  
##  Max.   :7.900   Max.   :4.400   Max.   :6.900   Max.   :2.500  
##        Species  
##  setosa    :50  
##  versicolor:50  
##  virginica :50  
##                 
##                 
## 

#Problem
#A) How Many Cases were included in the data?
  dim(iris)

## [1] 150   5

  #[1] 150 5 <- implies there are 150 cases

#B) How many numerical variables are included in the data? Indicate what they are, and if they are continuous or discrete
  
  colnames(iris)

## [1] "Sepal.Length" "Sepal.Width"  "Petal.Length" "Petal.Width" 
## [5] "Species"

  #there are four numerical variables:
  
  #"Sepal.Length" "Sepal.Width" 
  # "Petal.Length" "Petal.Width"
  
  #each of the variables are continuous as they are measurements of length and width

#C) How many categorical variables are included in the data, and what are they? list the corresponding levels
  #There is one categorical variable: Species
  summary(iris$Species)

##     setosa versicolor  virginica 
##         50         50         50

   #setosa versicolor  virginica 
    #    50         50         50 

fivenum(iris$Sepal.Length)

## [1] 4.3 5.1 5.8 6.4 7.9

#[1] 4.3 5.1 5.8 6.4 7.9

fivenum(iris$Sepal.Width)

## [1] 2.0 2.8 3.0 3.3 4.4

#[1] 2.0 2.8 3.0 3.3 4.4

fivenum(iris$Petal.Length)

## [1] 1.00 1.60 4.35 5.10 6.90

#[1] 1.00 1.60 4.35 5.10 6.90

fivenum(iris$Petal.Width)

## [1] 0.1 0.3 1.3 1.8 2.5

#[1] 0.1 0.3 1.3 1.8 2.5