Update EPA link

eda_checklist.Rmd

@@ -56,7 +56,7 @@ The next task in any exploratory data analysis is to read in some data. Sometime
 
 We won't go through the pain of cleaning up a dataset here, not because it's not important, but rather because there's often not much generalizable knowledge to obtain from going through it. Every dataset has its unique quirks and so for now it's probably best to not get bogged down in the details.
 
-Here we have a relatively clean dataset from the U.S. EPA on hourly ozone measurements in the entire U.S. for the year 2014. The data are available from the EPA's [Air Quality System web page](http://aqsdr1.epa.gov/aqsweb/aqstmp/airdata/download_files.html). I've simply downloaded the zip file from the web site, unzipped the archive, and put the resulting file in a directory called "data". If you want to run this code you'll have to use the same directory structure.
+Here we have a relatively clean dataset from the U.S. EPA on hourly ozone measurements in the entire U.S. for the year 2014. The data are available from the EPA's [Air Quality System web page](https://aqs.epa.gov/aqsweb/airdata/download_files.html). I've simply downloaded the zip file from the web site, unzipped the archive, and put the resulting file in a directory called "data". If you want to run this code you'll have to use the same directory structure.
 
 The dataset is a comma-separated value (CSV) file, where each row of the file contains one hourly measurement of ozone at some location in the country.