Class 27: Psychokenesis


In the Pear experiments using the Random Event Generator, a single trial provides a number between 0 and 200 which in effect represents the number of heads if you toss a coin 200 times. What is the expected number and standard deviation for the outcome of a single trial?

In one of their papers, Pear researchers show the record of a subject who did 5000 trials in each of the three modes: pk+, BL, and pk-. In the pk+ mode the subject tries to make the outcomes of the trials larger than would occur by chance, in BL the subject tries to make it the same as would occur by chance, and in pk- the subject tries to make the numbers smaller than would occur by chance.

The averages over the 5000 trials were 100.264 for pk+, 99.509 for pk-. Do these represent signficant differences from what you would expect if the subject had no effect on the outcomes?

The authors comment that the data for when the subject is in the BL modes seems to fit the expected values too well? What do they mean by this?

In these experiments the researchers did not try to control the number of times a subject could participate. If there was a tendency for subjects who succeeded in one session to try again would this make it more likely that the results would be significantly different than by chance? Answer the same question if they were allowed to quit at any time during the session.

At a recent gambling conference a Casino owner made the following remark: If we took the 0's off the roulette wheel, we would still make all kinds of money since most gamblers would still come in and play until they have lost their money and then leave. What do you think?

Has the PEAR lab changed your opinion about ESP? What would the PEAR lab have to do in order to a) make you a believer, if you are not already, b) convince the scientific community, and c) convince the general population?

Homework for Monday, April 22

Read Chapters 23 and 26 in FPPA. Do review exercises 1, 3, 8, 10, 12 in Chapter 23 and review exercises 1, 4, 6, 9, 12, in Chapter 26.


1) Give your thoughts about ESP and the PEAR lab.

2) Laurie has bet Linda that she won't be able to produce significant results if she tries the Random Event Generator. He's offered her 10 to 1 odds. Should Linda take the bet?