“Lies, damned lies and statistics” (Mark Twain)
“Do not trust any statistic you did not fake yourself” (Winston Churchill)
There is a classic book called “How to lie with Statistics” that I read many, many years ago (actually decades ago!) as a college student. If you’re ever looking for an inexpensive but fun and impactful present for a young student/graduate with the hidden agenda of getting that person interested in math and statistics, this is the one! The book taught me to take with a grain of salt pretty much anything and everything number-related. Anywhere! Whether it’s in the news or in the Personal Finance blogging world and even (particularly?!) in academia. I’m not sure if I was already a severely suspicious (paranoid?) person before reading this or the book turned me into the person I’m today. So, inspired by that book, I thought it would be a nice idea to write a blog post about the different ways numbers are misrepresented in the FIRE/Personal Finance arena. And just to be sure, this post is not to be understood as a manual for fudging numbers, but – in the spirit of the “How to Lie With Statistics” classic – serves as a manual on how to spot the personal finance “lies” out there!
And there’s a lot of material! Probably enough for at least one more followup post, so for today’s post, I look at just four different way of how quantitative financial issues are frequently fudged in the personal finance world. And a side note about the slightly attention-grabbing title I used here: Well, I put the word “Lie” in quotation marks to show to the faint-hearted that this is a bit tongue-in-cheek. I could have written, “fudge the numbers” or “Enron-accounting” or “How we delude ourselves in personal finance,” or something like that. Also, Hanlon’s Razor (“don’t attribute to malice what can be explained by incompetence”) comes to mind here, but I’m not sure if those faint-hearted folks feel that incompetence is a significantly more benign explanation than malice.
So, let’s look at some of my favorite examples of how people lie to themselves (and others) in the realm of personal finance…