Saturday, October 8, 2011

"Lies, Damn Lies, and Statistics."

That quote is from Mark Twain (I THINK) and it was never more true than today, especially as the political season heats up. I'm leery of another person's statistics, especially when they don't site their source. Statistics are a funny thing; they can make us believe almost anything. Take, for example, this gem from the 70's, "half of all marriages end in divorce". Not only is this not true today but it wasn't even true when it was originally quoted. In a particular year (sometime in the 70's, I forget exactly when) there were half as many divorces as there were marriages. Some news agency got ahold of that particular stat and said "Wow, that must mean that half of all marriages end in divorce", as if, for example, 2000 marriages occurred that year and 1000 of those couples got divorced in the very same year. Ridiculous of course. That particular stat doesn't take into account all of the marriages in the history of time. When you think about it, really think about it, the statistic is simply unbelievable on the face of it. Even so, people are still quoting it today. I've quoted it and I bet you've quoted it. Un-friggin-believable. When I'm taken in by a patently ridiculous statistic I feel particularly stupid. However, that stat is, I think, just a case of misinterpreting the data. I don't THINK the mis-information was intentional.

Here's one that is. A friend of mine recently posted this graph. Now the data may be true (I don't really know) but is it useful and does it give a true picture of a very real problem? No it does not. All this graph does is say "Republicans are bad; Democrats are good." Stupid and pointless and not just because Presidents have less control over debt than this graph would suggest. (PLEASE NOTE: I am NOT saying my friend is stupid. He is not. He is a thoughtful and intellegent man. I'm only saying the graph is pointless.) Why? Because as the debt increases in REAL dollars the increased portion becomes a smaller percentage of the total. Let me show you. During GWB's administration the National Debt went from 5.8 Trillion to 10 Trillion. That's an increase of just under 4 Trillion in 8 years. So far during BHO's administration the debt has gone from 10 Trillion to 14.7 Trillion, an increase of 4.7 Trillion in two years. By the way here's my source http://www.treasurydirect.gov/govt/reports/pd/histdebt/histdebt_histo5.htm and here http://www.treasurydirect.gov/NP/BPDLogin?application=np  Just in case I got the numbers wrong. My point is that, though possibly true, the graph doesn't tell a meaningful story. That is, of course, unless your story is "Republicans are bad and Democrats are good". As an aside, I don't personally care either way. I know that the House of Representatives controls the purse strings and, although a President has the influence of the "Bully Pulpit" he really doesn't have that much control. (The decisions made during the Regan administration are a completely different animal altogether and won't be dealt with here and now (though maybe later).

Here's what I'm saying; When you read a statistic think about what the person quoting it is trying to get you to believe. Their purpose is almost never altruistic.

As I use to tell me kids "That's a mighty big number [Missy] you might want to check that."

1 comment:

  1. Wow, great food for thought, thanks for making such an important point.

    (And since the time that you reminded me to check the numbers, I have learned they are all too true, and may be even horrible than reported. Tremendously sad.)

    ReplyDelete