Sunday, August 06, 2017
A Summertime Project
UPDATE: 22 NOV 2017: To my surprise, there is a small literature on local economic conditions such as gas prices, overall economic evaluations, and political outcomes such as presidential voteshare. The literature includes: Abrams & Butkiewicz, 1995; Ansolabehere, Meredith & Snowberg, 2013 & 2014; Books & Prysby, 1999; Brunk & Gough, 1983; Reeves & Gimpel, 2012; Weatherford, 1983.
UPDATE, 28 OCT 2017: The Pearson correlation between Trump approval and the Big Smoke regular gas price over the past 210 days is -.45, a moderate level.
I have been creating a long-term data set of two variables: President Trump's daily approval rating as published by Gallup (http://www.gallup.com/poll/201617/gallup-daily-trump-job-approval.aspx) and the daily price of regular gas at my local gas station, the Tesoro Big Smoke station on Franklin Road between Meridian Road and Linder Road in Meridian. I started this project at the beginning of April and will continue it into the foreseeable future.
I have to confess that this is a correlative project and not particularly causal in nature. I do not see an explicit link between President Trump's actions in Washington, D.C. and the price of a basic commodity in distant Idaho. (My area is called the most geographically isolated urban area in the U.S., a full 5 1/2 hours away in driving time from the nearest urban center, Salt Lake City.) Yet both fluctuate, Trump on a daily basis as rarely does he retain the same percentage support day after day, and gas on a weekly basis as prices bounce up and down based on supply and demand.
So far, the correlation from April 1st until today is slight: the Pearson correlation is = -.19, meaning that as prices for gas increase, the president's popularity decreases, but by a very slight amount. Much of this relationship surely can be accounted for by factors other than any direct linkage between the two. For instance, it is well known that as demand for gas increases during the summer vacation and driving seasons, prices will increase, and this summer is no exception, rising from $2.35 a gallon in April to $2.55 today. The president's approval rating has been in a gradual descent since the spring, with his average daily approval rating in April being 39% while in July it was 38%.
If nothing else, this is a good exercise in restating the dictum that correlation is not the same as causation!
