Airquality Assignment

Author

Gamaliel Ngouafon

Airquality Assignment

Load in the library

library (tidyverse)
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Load the dataset into your global environment

data("airquality")

Look at the structure of the data

View the data using the “head” function

head(airquality)
  Ozone Solar.R Wind Temp Month Day
1    41     190  7.4   67     5   1
2    36     118  8.0   72     5   2
3    12     149 12.6   74     5   3
4    18     313 11.5   62     5   4
5    NA      NA 14.3   56     5   5
6    28      NA 14.9   66     5   6
mean(airquality$Temp)
[1] 77.88235

Used the matrix format to select column 4(Temperature) from airquality dataset

mean(airquality[,4])
[1] 77.88235

Calculate Median, Standard Deviation, and Variance

median(airquality$Temp)
[1] 79
sd(airquality$Wind)
[1] 3.523001
var(airquality$Wind)
[1] 12.41154

Rename the Months from number to names

airquality$Month[airquality$Month == 5]<- "May"
airquality$Month[airquality$Month == 6]<- "June"
airquality$Month[airquality$Month == 7]<- "July"
airquality$Month[airquality$Month == 8]<- "August"
airquality$Month[airquality$Month == 9]<- "September"

Now look at the summary statistics of the dataset

summary(airquality$Month)
   Length     Class      Mode 
      153 character character 

#Month is a categorical variable with different levels, called factors.

airquality$Month<-factor(airquality$Month, 
                         levels=c("May", "June","July", "August",
                                  "September"))

Plot 1: Create a histogram categorized by Month

Plot 1 Code

p1 <- airquality |>
  ggplot(aes(x=Temp, fill=Month)) +
  geom_histogram(position="identity")+
  scale_fill_discrete(name = "Month", 
                      labels = c("May", "June","July", "August", "September")) +
  labs(x = "Monthly Temperatures from May - Sept", 
       y = "Frequency of Temps",
       title = "Histogram of Monthly Temperatures from May - Sept, 1973",
       caption = "New York State Department of Conservation and the National Weather Service")  #provide the data source
p1
`stat_bin()` using `bins = 30`. Pick better value `binwidth`.

Plot 2: Improve the histogram of Average Temperature by Month

Plot 2 Code

p2 <- airquality |>
  ggplot(aes(x=Temp, fill=Month)) +
  geom_histogram(position="identity", alpha=0.5, binwidth = 5, color = "white")+
  scale_fill_discrete(name = "Month", labels = c("May", "June","July", "August", "September")) +
  labs(x = "Monthly Temperatures from May - Sept", 
       y = "Frequency of Temps",
       title = "Histogram of Monthly Temperatures from May - Sept, 1973",
       caption = "New York State Department of Conservation and the National Weather Service")
p2

Plot 3: Create side-by-side boxplots categorized by Month

p3 <- airquality |>
  ggplot(aes(Month, Temp, fill = Month)) + 
  labs(x = "Months from May through September", y = "Temperatures", 
       title = "Side-by-Side Boxplot of Monthly Temperatures",
       caption = "New York State Department of Conservation and the National Weather Service") +
  geom_boxplot() +
  scale_fill_discrete(name = "Month", labels = c("May", "June","July", "August", "September"))
p3

Plot 4: Side by Side Boxplots in Gray Scale #Plot 4 Code

p4 <- airquality |>
ggplot(aes(Month, Temp, fill = Month)) + 
  labs(x = "Monthly Temperatures", y = "Temperatures", 
       title = "Side-by-Side Boxplot of Monthly Temperatures",
       caption = "New York State Department of Conservation and the National Weather Service") +
  geom_boxplot()+
  scale_fill_grey(name = "Month", labels = c("May", "June","July", "August", "September"))
p4

Plot 5: Side by Side Boxplots of moth and wind speed

p5<- airquality |>
  ggplot(aes(x = Month, y = Wind, fill = Month)) +
  geom_boxplot() +
  labs(title = " Wind Speed Across Summer Months",
       x = "Month",
       y = "Wind speed (mph)")
p5

Airquality dataset contains environmental characteristics of New York city in order to determine it’s airquality. Plot 5, the last plot, depicts whether the summer month gets windier as time goes by. The dataset contains the average wind speed recorded from May to September. Those two variables are visualized through the box plot above using ggplot to give interesting insights about the observations. The box plot illustrates metrics like median, quartiles, maximum, and minimum values of each observations recorded for each month. For example, months like May, August and September have more disperse values recorded than July and June, due to the width of their boxes being wider. In other words, the average wind speed in June and July were closer and similar than the average wind speed in May, August, and September. Also, though may is shown to have the highest wind speed of the summer, there is no evident relationship or pattern, to argument the idea that New York get’s windier as the summer goes by. For example July is smaller in width and maximum value than August.