# Homework 5, STAT 542

# Chapter 8 exercises:

# Problems 1, 2, 5, 8, 9

# No R needed for these.



# Chapter 14, Problem 3:

library(tidyverse); library(mdsr)
library(lubridate)
example <- c("2015-03-20 18:45:00", "2015-06-21 12:38:00", "2015-09-23 04:21:00", "2015-12-21 23:48:00")
converted <- ymd_hms(example)

# install.packages("macleish")
library(macleish)
head(whately_2015)

ch14p3 <- ggplot(data = whately_2015, aes(x = when, y = temperature)) + 
  geom_line(color = "darkgray") +
  xlab(NULL) + 
  ylab("Temperature (degrees Celsius)") + 
  geom_vline(xintercept = converted[1]) + 
  annotate(
    "text", x = converted[1], y = 25, 
    label = "Vernal equinox", hjust = "left"
  ) + 
  geom_vline(xintercept = converted[2]) + 
  annotate(
    "text", x = converted[2], y = -10, 
    label = "Summer Solstice", hjust = "right"
  ) + 
  geom_vline(xintercept = converted[3]) + 
  annotate(
    "text", x = converted[3], y = -5, 
    label = "Autumnal equinox", hjust = "left"
  ) + 
  geom_vline(xintercept = converted[4]) + 
  annotate(
    "text", x = converted[4], y = 25, 
    label = "Winter Solstice", hjust = "right"
  )
ch14p3

# A little extra credit (one way to do it):

ch14p3 +
  annotate(
    "text", x = converted[1], y = 34, color="blue",
    label = "WINTER", hjust = "right", size=8
  ) +
  annotate(
    "text", x = converted[2], y = 34, color="green",
    label = "SPRING", hjust = "right", size=9
  )+
  annotate(
    "text", x = converted[3], y = 34, color="red",
    label = "SUMMER", hjust = "right", size=8
  )+
  annotate(
    "text", x = converted[4], y = 34, color="brown",
    label = "FALL", hjust = "right", size=10
  )


# Chapter 14, Problem 6:

# install.packages('AER')
library(AER)
# install.packages('ggExtra')
library(ggExtra)

data(HousePrices)

p <- ggplot(HousePrices, aes(x = lotsize, y = price)) +
  geom_point() +
  theme_classic() +
  stat_smooth(method = "loess", formula = y ~ x, size = 2)
ggExtra::ggMarginal(p, type = "histogram", binwidth = 3)

# Chapter 14, Problem 7:

library(tidyverse); library(mdsr)
library(shiny)

# install.packages("palmerpenguins")
library(palmerpenguins)
head(penguins)

# See ui.R and server.R files for this problem, and run them by something like:

source("Z:/Z from MATHSTAT/My Documents/teaching/stat_542/ch14pr7_Shiny_app/ui.R")
source("Z:/Z from MATHSTAT/My Documents/teaching/stat_542/ch14pr7_Shiny_app/server.R")

runApp("Z:/Z from MATHSTAT/My Documents/teaching/stat_542/ch14pr7_Shiny_app")