Lab 8 - Flint - Instructions-3

Lab 8 – Flint Water NAME 1 – NETID NAME 2 – NETID [if applicable] NAME 3 – NETID [if applicable] Formatting Instructions - Please submit your lab report as a pdf to Gradescope. - When you upload to Gradescope, please match pages with the question number . - Be sure that all group members are added in your submission to Gradescope (click view/edit group on the top right of the page once shown your final submission after matching pages). Assignment Overview - We’ll be investigating some data on water samples taken from Flint, Michigan in 2016, during the water crisis. We have the following analytical goals for this lab: o Evaluate the extent to which lead levels are unsafe across a representative sample of homes in the area o Investigate whether letting the faucet “flush” for a period of time lowers lead levels o Determine whether lead levels vary across wards (i.e., regions of the city). STEP 0 - Pre-lab work: Complete the pre-lab tutorials (“Customizing ggplot2” and “if else statements”) for Lab 8 first: https://stat212-learnr.stat.illinois.edu/ - Download the flint.xlsx file to your computer and then import into your RStudio session. o On the pop-up screen when importing, click the drop-down under “Ward” and change it to a character variable . Then click “Import” on the bottom right. o If using RMarkdown , put the following code after your import code to allow Ward to be read categorically. Flint$Ward = as.character(Flint$Ward) - Create a new R script (or use the RMarkdown file if you are using that option) - Remember to library(tidyverse) so that you can use the ggplot function. Data Description This data set includes lead content measurements taken from tap water across 300 homes in Flint, Michigan (of which 269 homes’ measurements are included). Researchers collected 3 water samples from each household: the water at first draw (faucet turned on), water after running the faucet for 45 seconds, and water after running the faucet for 2 minutes. Lead content is measured in parts per billion (ppb). The spreadsheet is organized such that one water sample is the unit of observation; there are 3 units of observation per household. As a point of reference, lead measurements above 5ppb are considered somewhat unhealthy for regular consumption, and lead measurements above 15ppb are considered dangerous for regular consumption. Variables SampleID: Household number. There are 269 households that provided data. Zip_Code: Household’s zip code Ward: The regional zone that the household was in. A ward is like a precinct. https://www.cityofflint.com/city-of-flint- ward-map/ Time: The time point at which the water sample was taken: First draw, after 45 seconds, or after 2 minutes.