Each correct card-call (or each successful trial) was termed a “hit.” During data analysis, scores from multiple runs were totaled and the mean chance expectation for that number of trials was found using a complex set of statistical calculations. After 1650 trials (sixty-six runs), the odds of the results being due to chance were calculated. Per Rhine, these odds would “require a number of 70 digits.” Additionally, shuffling bias was disproved, as the first twenty-five runs were performed with newly printed decks, and these runs presented the same hit rate as the later runs with the twenty-five decks (approximately nine hits per run of twenty-five cards). 

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            The second series of clairvoyant card-calling trials centered around the same subject: HP. This series of 1625 trials (or sixty-five runs) was conducted in the same way as the previously described trials with one exception: the card calls were made before the deck was touched (i.e., shuffled and cut). The call-record was checked against the order of the cards after the deck was shuffled and cut; the probability of the results having occurred purely due to chance were on the order of 10^20. 

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            The third and final series of clairvoyant card-calling trials described in Rhine’s article centered again around HP but were performed with Dr. J.G. Pratt as the observer. In these trials, the subject and the observer were located in two different buildings on campus. They synchronized their watches prior to the experimental trials. At a predetermined time, Dr. Pratt took the top card off of the shuffled deck and, without looking at it, laid it face down on the table. Thirty seconds later, HP called the card and recorded his call. Another thirty seconds passed before Pratt replaced the first card on the table with a second card, moving the first card to a “discard” pile. This was repeated until all twenty-five cards were called; following the runs performed during each sitting, the records were sealed. In this series of trials, as in the last two series described, the results were statistically significant. 

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            A note: the use of a mechanical shuffler in later studies did not impact the hit rate.

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          Rhine’s telepathic thought-transmission trials, unlike the clairvoyant card-calling trials, did not require a deck of twenty-five cards. They required the same five symbols (star, plus, wave, rectangle, circle), this time to be potentially transferred from the observer to the subject through thought alone. In these experiments, the imagining of one symbol counted as one trial. Like the card-calling experiments, twenty-five symbols, or trials, comprised a run. 

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            The first series of telepathic thought-transmission trials centered around a single percipient, George Zirkle (GZ). Like HP, GZ was discovered to be an unusually talented subject among a large cohort of subjects. Sara Ownbey served as the observer in these trials–both she and GZ were graduate students in Duke’s Psychology department. 

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            For each trial, Ownbey randomly chose one of the five symbols to imagine and to “send” to the percipient. Ownbey was practiced in varying the order of her symbol choices–statistical analysis (3) on the part of Rhine proved that her order was, indeed, random. It should also be noted that a fan was turned on during each run to eliminate the potential for whispering. 

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            The percipient–GZ–called out the symbol he had perceived or guessed, and the observer recorded it before “sending” another symbol. This process was repeated twenty-five times per run and across varying distances for different runs–the hit rate did not decrease with increasing distance. No statistical computation was performed because the hit rates were so high (this is quite unusual): The lowest hit rate of the first twelve runs was fourteen and the highest was twenty-three. One of the 950 runs yielded a hit rate of twenty-five–a perfect score.