data_exploration.Rmd

---
title: "Exploration of Car Crash Data"
output: html_notebook
---

# Load the data

```{r}
library(readr)
print(getwd())
crash_data_dir = "../source_data/crash_data"
all_files = list.files(crash_data_dir, pattern="csv$", recursive=TRUE)

read_crash_file <- function(file_type) {
  read_csv(list.files(path = crash_data_dir, 
                             pattern = paste0(file_type, 
                                              "_[[:digit:]]{4}_Statewide.csv"), 
                             recursive = TRUE, 
                             full.names=TRUE))
}
# commveh = read_crash_file("COMMVEH")
crash = read_crash_file("CRASH")
# cycle = read_crash_file("CYCLE")
# flag = read_crash_file("FLAG")
# person = read_crash_file("PERSON")
# roadway = read_crash_file("ROADWAY")
# trailveh = read_crash_file("TRAILVEH")
# vehicle = read_crash_file("VEHICLE")
```

# Visualize the data with regression line

```{r}
library(ggplot2)
library(dplyr)
library(lubridate)

crash %>% 
  mutate(CRASH_DATE = ym(paste0(CRASH_YEAR, CRASH_MONTH))) %>% 
  count(CRASH_DATE) %>% 
  ggplot(aes(x = CRASH_DATE, y = n)) +
  geom_smooth()
ggsave("pandemic_crash_regression.png")
```
# Visualize data as a line plot

```{r}
crash %>% 
  mutate(CRASH_DATE = ym(paste0(CRASH_YEAR, CRASH_MONTH))) %>% 
  count(CRASH_DATE) %>% 
  ggplot(aes(x = CRASH_DATE, y = n)) +
  geom_line()

ggsave("pandemic_crash_line.png")
```