Street Lamps and Confirmation Bias

I’ve been gone for the whole weekend at the “CFI Convocation” in Buffalo to meet with other completely awesome student freethought group leaders and I had a completely awesome time, but more on that later. To ease myself back into blogging I’ve chosen to address and article which I just found about “Street Light Interference” in the Epoch Times.

“A man walks near a streetlight and it turns off. As he continues down the street the light turns back on again. Is this an explainable electrical phenomenon or the product of unknown energies?”

Admit it, being able to walk under a streetlight and have it turn on or off is the most fascinating, important, and coolest thing you can possibly think of besides Batman! Why else would somebody write a book on the subject?

Well, okay. Maybe it wouldn’t shatter the world around me if I learned that my presence controlled street lights… but how cool would it be to have a telepathic version of The Clapper? Instead of using all that energy to clap your hands together to turn the lights on, you could just think and have them go on. Wouldn’t be as sexy as hearing Captain Picard’s voice say “Computer, lights” but…

Hell, if electrical activity from our brains can affect street lights several meters above our heads, why can’t we refine this telepathic control over electronics so that I can type blog posts from across the room while cooking yummy food?

But the real question here is not what the practical applications of the phenomenon are nor how interesting it is. The question is if there is paranormal phenomena taking place around people.

Now, I’d like to make it pretty clear that I haven’t really investigated this phenomenon much so I can’t really say whether or not it really is there. However, I can express skepticism about what I think is actually going on.

Let’s first establish the fact that light bulbs burn out. The filament inside will break or something and the light is no longer able to conduct electricity. Thus, no electrons flow through the filament and since you need electrons to flow through the filament to generate light, you have no light.

Next, let’s establish the fact that when light bulbs near the end of their lives, they will often flicker. Flickering isn’t necessarily fast. The light bulb can appear dead for quite some time and suddenly release a flash of light and go dark again.

There are many street lights that go on every night when a certain level of darkness is reached and they are on all night long. Now we are beginning to see that it is not at all unlikely that many light bulbs in any given city at any given time are nearing the end of their lives.

So is it a huge surprise when a light mysteriously goes out just as you’re passing by?

Of course, you wouldn’t have seen it go out if you weren’t passing by. We have no idea how many street lights go out when nobody is there to see them. The other thing is, we don’t notice when street lights don’t go out. It seems perfectly normal that street lights would not go out. Unless these people are really keeping a tally of how many street lights stay on versus the ones that go out then they have no real good evidence that there is something going on which is way outside of statistical probabilities.

There are two very good questions we should be asking ourselves instead of “do lights sometimes go out when we’re passing by?”

  1. Do lights often go out when nobody is watching?
  2. How often do the lights not go out when you’re passing underneath?

They sound like boring questions, but they are the ones that need to be asked to see if there is a phenomenon worth investigating. When a person does something like “counting the hits and forgetting the misses” we call that “confirmation bias”.

To the article’s credit, it did present a bit of a skeptical point of view which I haven’t mentioned yet in this post:

Some skeptics suggest that SLI occurs as a consequence of lights near the end of their life. The globes of sodium (amber) bulbs, or mercury for blue lights, possess security systems that regulate the temperature the lights can reach. These are the two types of streetlights most used in public lighting, and it is not unusual to encounter some lights that begin to fail when the temperature of the gases falls outside of the normal range. A system of electric supply interruption makes these streetlights go without light for a few minutes, until the temperature goes down and a new impulse of high tension makes them turn on. This effect, skeptics argue, could easily occur when a suggestible individual interested in paranormal phenomena passes below as things go dark.

And then it said:

Even so, the intermittent illumination of aging streetlights still does not resolve many of the cases of SLI.

Wait, why? Again, what evidence is there that there’s something going on which is sufficiently statistically improbable to warrant not saying it’s probably just chance?

But, maybe something is going on here. We just don’t know.

Until one of these “SLIders” goes for one of the many available paranormal challenges out there and gets tested we probably will have to give a half-hearted slice of Occam’s Razor and say it’s much more likely that they are falling victim to confirmation bias than it is that their brains are generating electrical fields which extend a good ten meters above them.

Wow. That was a really boring post about street lamps.

Don’t look at me! If you wanted to be entertained you would have gone to see Batman, not read Teen Skepchick!

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  1. Joy Wang
    July 22, 2008 at 5:25 pm —

    Or a real life version of Dumbledore’s Deluminator! Why do paranormal/pseudoscientific ideas/groups lend themselves to easy acronymization (IDiots, iDIots, SLIders…whoops, confirmation bias, UFO doesn’t work)?

    I’ve had lightbulbs die on me once I turned them on, but it’s happened to virtually everyone I know who uses lightbulbs. Does that mean we can magically turn off lights with our minds?


    When I look at candles, they flicker. Can’t I make candles flicker with my mind?

    I don’t think so. If you could test this, you’d probably find that street lights go out more often when no-one’s standing there. Think about it. The chances of it going out just as someone walks by are incredibly slim compared to that of them going out when nobody’s around (unless, of course, there’s always people standing under the light)…

    You’ve gotta admit though, there’s nothing like street lamps to get you in the mood for skeptical blogging.


  2. thecoolestgeeK
    July 22, 2008 at 8:30 pm —

    Of course the lights probably do go off more often when nobody’s there to see them… Still, I wouldn’t imagine these people would want to test their “powers” accurately if it meant they might be proved wrong. They want to feel special, and wouldn’t you feel special too, if you could control streetlamps? Think of all the endless possibilities!

    Sadly, many people around the world are afflicted by Confirmation Bias, or CB. It’s really gotten out of hand lately…I mean this guy wrote a whole book about “Streetlight Interference”? How much free time has he got on his hands?

    P.S. –
    Noticed how I capitalized “Confirmatin Bias” and abreieviated it to CB to make it sounds almost like an illness? See how easy it would be for this guy to make a burnt-out lightbulb turn into Streetlight Interference or “SLI” and make it sounds so official?

  3. w_nightshade
    July 23, 2008 at 9:28 am —

    That sounds like one of the lame superpowers from Mur Lafferty’s podcast novel “Playing For Keeps” ( Featured powers include:
    1) The ability to lift a bar tray of any weight or mass distribution.
    2) The ability to cook anyone’s ideal meal.
    3) The ability to get an elevator to arrive just as you press the button.


  4. July 23, 2008 at 10:32 am —

    Don’t look at me! If you wanted to be entertained you would have gone to see Batman, not read Teen Skepchick!

    I find them both extremely entertaining. I mean, one features a dude dressed like a flying rat for chrissake. And Batman is pretty good, too.

  5. July 24, 2008 at 9:39 pm —

    That’s pretty curious. The exact thing happened to my daughter (10) and I in Cape May Point, NJ a few weeks ago. She was a little freaked out because I kept telling her the alleged ghost stories about the Point and we walked under the light and it went out. We walked over the dunes and returned only, like, 4 minutes later and the light was back on at basically full strength. I told her that I had just heard of this normal occurrence but how someone might think it was paranormal.

  6. MaggieMoo
    July 28, 2008 at 6:46 pm —

    OMG guys i found a vid of Tom Cruise talking about scientology!!

    im scared!!

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