Q4: Import the bike sharing dataset

bike <- read.csv("bike_sharing_data (1).csv")

Q5: Number of observations and variables

dim(bike)
## [1] 17379    13

Q6: Data type of humidity

class(bike$humidity)
## [1] "character"

Q7: Season in row 6251

bike[6251, "season"]
## [1] 4

Q8: Count observations by season

table(bike$season)
## 
##    1    2    3    4 
## 4242 4409 4496 4232
sum(bike$season == 1)
## [1] 4242

Q9: Example of multiple conditions

head(subset(bike, season %in% c(1, 2) & windspeed >= 40))
##             datetime season holiday workingday weather  temp  atemp humidity
## 1008 2/14/2011 15:00      1       0          1       1 22.96 26.515       21
## 1010 2/14/2011 17:00      1       0          1       1 18.86 22.725       33
## 1011 2/14/2011 18:00      1       0          1       1 16.40 20.455       40
## 1015 2/14/2011 22:00      1       0          1       1 13.94 14.395       46
## 1018  2/15/2011 1:00      1       0          1       1 12.30 12.120       42
## 1019  2/15/2011 2:00      1       0          1       1 11.48 11.365       41
##      windspeed casual registered count          sources
## 1008   43.9989     19         71    90 www.google.co.uk
## 1010   40.9973     25        218   243      ad campaign
## 1011   40.9973     11        194   205      ad campaign
## 1015   43.9989      1         44    45 www.google.co.uk
## 1018   51.9987      0          5     5    www.google.fi
## 1019   46.0022      1          2     3    www.google.fi

Q10: High wind during winter or spring

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