The Correlation Game

Fri, Apr 25, 2008 | Jared Woodard

Market Commentary

A fun game on a slow Friday afternoon: take the front page headline on Yahoo Finance, and perform some desirable action if the headline makes a dubious assumption about causation.  Move to the next headline, and repeat.  We were going to suggest this as a drinking game, but we don’t want everyone drunk before the market’s even closed.

Felix Salmon makes this point well.  Financial journalists, for whatever reason, constantly report on correlated events (“Today, p occurred after news that q”) with sufficient ambiguity as to leave the reader with the impression that q caused p.  As every freshman philosophy student learns (or used to learn, anyway), correlation does not imply causation.  Enough pontification, let’s play…

“Oil prices rose sharply Friday on news that a ship under contract to the U.S. Defense Department fired warning shots at two Iranian boats.”  Really?  Did the Associated Press talk to traders at the NYMEX who were all, “OMG warning shots, buy buy buy!!!”  No.  Isn’t it just as likely that after yesterday’s heavy selling in the energy sector, some mean reversion was due?  Isn’t it also just as likely that oil rose in price for no discrete or knowable reason whatsoever?  The point here is that unless you’ve got a defensible causal chain to report on, it’s sloppy to be casting prepositions all over the place that leave readers with the impression that causality has occurred.

The story goes on to undermine its own headline with an account of how non-unique these saber-rattling sorts of events are.  It follows up with the concession that, “On Friday, oil prices were already up before the report on news of a pipeline attack in Nigeria and a looming refinery strike in Scotland,” and then continues anyway with commentary on one of the perennial bugbears of oil reporting, namely shenanigans in Nigeria.

Sadly, the story does not achieve oil cheerleading nirvana inasmuch as it fails to include a quote from T. Boone Pickens.

Tags: , , , , , , , ,

0 Comments For This Post

3 Trackbacks For This Post

  1. Punctured Rally | Condor Options: Iron Condor Trading Newsletter Says:

    [...] know-nothings in the financial press can’t keep from dancing. On days like this The Correlation Game becomes irresistible, so let’s [...]

  2. Dow Slips Below 12k on Whatever Random News | Condor Options: Iron Condor Trading Newsletter Says:

    [...] got a round of the correlation game started this afternoon, but it went nowhere fast: either headline writers are getting smarter, or [...]

  3. Correlation, Causation, and Expiration | Condor Options Says:

    [...] Tim Geithner is likely to be nominated as the next secretary of the Treasury.” We’ve  pointed out that correlation is not the same as causation, but what if we give the benefit of the doubt and say [...]


Jared Woodard specializes in trading volatility as an asset class. With over a decade of experience trading options and other volatility products ... Read More


Open All | Close All