R Workshop Day 2 (pdf)

RStudio projects and RMarkdown

We will be working with the “driving” dataset:
- Start a new project
- Start a new RMarkdown document
- Add a R-chunk to the document, that contains the code to load the packages hanoverbase and ggformula.
- Download this file
- Upload the file into your new project space
- Import the dataset into your RMarkdown document, but on the Import window screen, after the data was appeared, do the following:
  - Select the first column heading (day), and change it to the “Date” format, with format string %Y/%m/%d.
  - For the “leaveTime” and “arrTime” columns, change their format to “Time” with format %H:%M. We learned these formats by looking at the actual file in a program like Excel and reading the documentation for col_date (try ?col_date).
  - Now copy the updated code in the import window and paste into a code chunk in your document (set it to show no output but run code). Remember to use the View line only in the console, not in the RMarkdown.
In a new chunk, use gf_histogram to draw a histogram of the leaveTime variable, and describe and explain the result.
Draw a similar histogram of the miles variable. What patterns do you notice?
Draw a scatterplot (gf_point) comparing miles and time, restricting to the part of the dataset where miles is at most 48.

Create a simple RMarkdown report that includes some data and graphics from one of the datasets we have used so far.
Choose 3-5 states and filter the counties data to these states. Then draw a scatterplot comparing the populations in 2000 and 2010, with a different color for each state, then add smooth lines for each state as well as overall. Add title and caption to the graph, set the x and y labels, and change the label that goes with the colors.