Thursday, January 29, 2009

DRUNKEN DOWSING: cherry picking

I want to talk a little bit about a logical fallacy called “Cherry Picking,” but first I should bring you up to date on the dowsing test that my friend and I are working on.
I was really pleased with what my dowsing friend Tom (not his real name) said at the last party. He suggested for the dowsing test I hide rebar in one of several PVC pipes. I went to Home Depot and purchased some 2 ½“ PVC and 4 pieces of rebar. I plan to cluster the 4 pieces of rebar together and place the cluster in one of five PVC pipes for him to pick.
I was thinking that the day of the test Tom could designate 5 spots in the backyard that he feels are clear of any interference. We could put towels down to mark those spots. I would then place the PVC pipes on those spots. He would use his dowsing ability to pick which PVC pipe contained the cluster of rebar. We would do this a number of times. Each time I would switch out which piece of PVC contained the rebar.
Tom thought each round should have 10 choices (10 pieces of PVC). I liked that idea also but thought it requires a big reset for each round. One person can’t reset 10 pieces of PVC easily and because I am horribly cynical, there is no way I’m letting anyone else touch the PVC. Knowing my friends they would quickly become bored between rounds and start wandering away perhaps into the nearby lake. That would be tragic. I thought 5 pieces of PVC would be a better number because we can just double it to figure out the percentage. If we do the test ten times, and Tom has only chance on his side, he should be able to choose the correct PVC twice. 5 choices for each round also make it easy for me to randomize my PVC choices because I can use dice. I will just ignore the number 6 whenever I roll it.
The idea of videotaping all of this (which I love) also came up. I have an award winning filmmaker friend who said he is ready to film. I am required by him to mention the award any time I talk about him. So, Youtube, here we come.
This brings me to “Cherry Picking.” Tom and I both agreed that we shouldn’t let anyone else try dowsing at the party until after the test is finished and the dowsing claim is confirmed (or not). Letting everyone try dowsing first off leads to a false positive on tests called “cherry picking the results.” Basically cherry picking goes like this: During the test, Tom might not be able to show a greater then chance ability to dowse but (given enough people trying) someone will. That is just how averages work. Some people do below average. Some people do above average. If you get ten people each to flip a coin, say four times, the overall average is going to be around 50%. But, one of those people might get four heads in a row (just as one of them might get four tails in a row). If the person who got four heads in a row didn’t know any better he or she would walk away from the test thinking that every time they flipped a coin it will come up heads. That is what would happen if we let everyone take a swipe at guessing were the pipe is. By sheer chance alone one of those people (say Mary) has to do better than chance, just as one of those people (say Sally) has to do worse than chance. And then Mary will walk away thinking she has some dowsing ability. Everyone will forget about the original claim Tom made about dowsing and instead focus on Mary and her amazing skill. The belief in dowsing would continue and I would be left alone drunk and naked passed out in the back yard. I’m not sure how the last part would happen but trust me it always does.

Wednesday, January 21, 2009


Here is the next installment of the dowsing test.

(DOWSER- TOM – not his real name)
Let’s make the Dowsing experiment into a kind of performance piece/party! I'll bring plenty of dowsing rods - I know that after I prove that dowsing is true, everyone will want to learn how. Maybe even you!

A test at a party would be great but not at the one coming up. We have not yet come up with the protocol for the experiment. And as the Wicked Witch of the West has said, "These things have to be done delicately."
I would love to learn how to dowse. You may not know this but there are a number of science organizations around the world which will award you large sums of money (we are talking a million dollars) if you can demonstrate to them that you can do what you claim. But we are getting a little ahead of ourselves. Why don't we see if you can dowse first? Then we can have a dowsing rave because you are going to be rich.
From what I have read these science groups usually start out their tests with a questionnaire to get the applicant to specify their claim, so that is what I am sending you.
I want to do this questionnaire thing through email because I think this experience would make a good article for one of those ponderous Skeptic magazines I'm always trying to get published in. Don't worry; I won't use your name. In fact, I'm hoping to get drunk enough at the dowsing party that I won’t want to use my name either.

PS, you can dress up like a guinea pig if you think that will help.

As a licensed science TV watcher I feel I am eminently qualified to administer this test. The following is a series of questions to help us agree on a protocol. Once you answer these questions, we can come up with some suggested parameters for the experiment. Feel free to email back to me any ideas you think might help, any rules that you would like to change, or any rules you cannot agree to. Also please add any excuse to drink alcohol during the test. I don’t think this will help the results but it will certainly make the experimenting more interesting.
Please answer the questions fully. Add any information or qualifications that you see fit. If you do not know the answer to a question or are unsure feel free to include that in your response. Or say “this is a dumb question.” Please include curse words only when needed.

1) As I understand it, you claim that by holding two bent metal surveyor flags in your hands (one in each hand) and walking around in a field, you can detect a pipe made of ferrous metal buried in the ground in that field. Is that correct? If you would like, please feel free to describe your ability in your own words.
2) What would you estimate is your success rate?
3) How far away from the point you indicate (radius) can the pipe be for you to still consider it a successful detection (hit)?
4) How deep can the pipe be for you to still consider it a hit?
5) If you pointed to a spot and did not find a metal pipe but instead found a terracotta, cement, plastic or PVC pipe would you still consider that a hit?
6) Are the pipes you detect always water pipes or can they be pipes carrying wires, sewage, fiber optics or gas?
7) Does electrical power running through the wires in the pipes affect your results?
8) Does your body act as an antenna and somehow focus energy in a way that facilitates detection?
9) Do the metal rods move in your hands by themselves or do you move them (even if just subconsciously)?
10) As you walk and search, do you continue standing straight up or do you have to crouch close to the ground? In other words, how much does distance from the ground affect your abilities?
11) How long does it typically take you to perform a detection?
12) Can you always perform this action or do you have good days and bad days?
13) Does the season or time of day affect your results?
14) Does rain, temperature, or weather affect your results?
15) If you are tired will your results change?
16) Does repeated testing affect your results?
17) Does the presence of other people or animals affect your results?
18) Does jeweler worn by other people affect your results?
19) Does drinking affect your results?
20) Will I be allowed to hold and inspect the surveyor flags before the experiment begins?
21) Will I be allowed to wear a lab coat while doing so?
22) Will what I am wearing under the lab coat affect your results?
23) Do you have favorite surveyor flags?
24) Do they have names?
25) Are the surveyor flags you use magnetized?
26) Will I be allowed to test whether they are magnetized by bringing them in contact with some other ferrous metals?
27) You mentioned that the force that you are detecting may or may not be magnetism. Will bringing your surveyor flags in contact with ferrous metals before the experiment have any effect on the results?
28) Does the presence of trees or nearby power lines affect your results?
29) Does the presence of drunken people affect your results?
30) I understand that the pipes you are able to find are made of ferrous metals. Am I correct in understanding that those pipes do not have to de magnetized for you to be able to detect them?
31) Would the presence of any of the following materials affect your results? water, wire, fiber optics, sand, cardboard, paper, cloth, wood, plastic, ice or alcohol.
32) As part of this experiment (and if you agree) I think I will be hiding a length of pipe in one of a number of cardboard or plastic boxes. If I use a pipe made of ferrous metal as the object of the test, what would you say is the shortest length that you would feel confident in detecting. Although I would like you to specify a short length to facilitate the test, I also want you to pick a length that would make you perfectly comfortable. What is the shortest length of pipe (and suggested diameter) that you feel that you can detect in a cardboard or plastic box?
33) If I did hide the pipe in a box, would a plastic box or a cardboard box be ok?
34) If we do use a metal pipe you will be allowed to approve and inspect the pipe. Before the beginning of the experiment the pipe will be checked to make sure it is not magnetized. If the pipe is checked for magnetism by bringing it in contact with other ferrous metals will that affect the outcome of the test.
35) Would putting sand in the boxes with the pipe (to equalize the weight and prevent the pipe from rolling in the box) affect the results?
36) Since I will suggest we perform this test in Claire and my backyard does the presence of a lake affect your results?
37) Since we will be, (I hope), in a party situation, when this experiment is performed, would people passed out in the backyard affect the results?
38) Will nudity affect the results? (I would like to make it clear that that last question is in no way related to what I will be wearing under my lab coat.)

Thursday, January 8, 2009


First off, I would like to say Happy New Year. I can’t seem to shake this nagging feeling that 2009 will be a really good year.
Recently our local, progressively minded, free newspaper, The Orlando Weekly, printed an article in which they asked local newsmakers what they thought 2009 will be like. They chose some county commissioners, a radio news personality, and some local charity board members to use their crystal balls to pear into the future. The responses the paper received were interesting but not outstanding with the exception of one, Kim Wade, resident “psychic” at a New Age Shop in Orlando called Avalon. I want to compliment Wade for her STUNNING AND DARING predictions for 2009.
Without the benefit of ESP, gay activist, Michael Wanzie foresees Florida’s ban on gay adoption being lifted in 2009. Kim Wade, on the other hand, went out on a limb to say “Political things will be front-row center” in 2009.
Because of the slowing economy, reporter, Mike Synan of WDBO radio was willing to predict the renovation of the Citrus Bowl would be canceled. By contrast, Wade, really put her money where her mouth was by predicting “We’re going to start tightening the belts.“ She wouldn’t even say “our belts.” because that would be too much of a commitment. She said “the belts.” Someone someplace will be tightening some belts that may or may not belong to them.
Even County Commissioner, Robert Stuart was weak in predicting a second national championship for the Florida Gators. But, Wade demonstrated a powerful, penetrating vision that burrows into the murky future like a laser by stating “We’re going to see more as far as – it’s not going to be so much the big guy as far as money, big time.” …… What???