Assignment 1 Code & Results

Question 4 – Import dataset (Base R)

bike <- read.csv("bike_sharing_data.csv")
head(bike)
##        datetime season holiday workingday weather temp  atemp humidity
## 1 1/1/2011 0:00      1       0          0       1 9.84 14.395       81
## 2 1/1/2011 1:00      1       0          0       1 9.02 13.635       80
## 3 1/1/2011 2:00      1       0          0       1 9.02 13.635       80
## 4 1/1/2011 3:00      1       0          0       1 9.84 14.395       75
## 5 1/1/2011 4:00      1       0          0       1 9.84 14.395       75
## 6 1/1/2011 5:00      1       0          0       2 9.84 12.880       75
##   windspeed casual registered count       sources
## 1    0.0000      3         13    16   ad campaign
## 2    0.0000      8         32    40 www.yahoo.com
## 3    0.0000      5         27    32 www.google.fi
## 4    0.0000      3         10    13   AD campaign
## 5    0.0000      0          1     1       Twitter
## 6    6.0032      0          1     1  www.bing.com

Question 5 – Number of observations and variables

dim(bike)
## [1] 17379    13

Question 6 – Data type of humidity

Instructor hint: str(bike)

str(bike)
## 'data.frame':    17379 obs. of  13 variables:
##  $ datetime  : chr  "1/1/2011 0:00" "1/1/2011 1:00" "1/1/2011 2:00" "1/1/2011 3:00" ...
##  $ season    : int  1 1 1 1 1 1 1 1 1 1 ...
##  $ holiday   : int  0 0 0 0 0 0 0 0 0 0 ...
##  $ workingday: int  0 0 0 0 0 0 0 0 0 0 ...
##  $ weather   : int  1 1 1 1 1 2 1 1 1 1 ...
##  $ temp      : num  9.84 9.02 9.02 9.84 9.84 ...
##  $ atemp     : num  14.4 13.6 13.6 14.4 14.4 ...
##  $ humidity  : chr  "81" "80" "80" "75" ...
##  $ windspeed : num  0 0 0 0 0 ...
##  $ casual    : int  3 8 5 3 0 0 2 1 1 8 ...
##  $ registered: int  13 32 27 10 1 1 0 2 7 6 ...
##  $ count     : int  16 40 32 13 1 1 2 3 8 14 ...
##  $ sources   : chr  "ad campaign" "www.yahoo.com" "www.google.fi" "AD campaign" ...
class(bike$humidity)
## [1] "character"

Question 7 – Season value at row 6251

Instructor hint: bike$season[6251]

bike$season[6251]
## [1] 4

Question 8 – Number of winter observations (season == 4)

Instructor hint: dim(subset(bike, season==4))

nrow(subset(bike, season == 4))
## [1] 4232

Question 10 – High wind (>= 40) during winter or spring

Instructor hint: dim(subset(bike, windspeed >= 40 & season %in% c(1,4)))

nrow(subset(bike, windspeed >= 40 & season %in% c(1,4)))
## [1] 46

End of Assignment