via Discovery News
A study published last year in a scientific journal claimed to have found strong evidence for the existence of psychic powers such as ESP. The paper, written by Cornell professor Daryl J. Bem, was published in The Journal of Personality and Social Psychology and quickly made headlines around the world for its implication: that psychic powers had been scientifically proven.
Bem’s experiments suggested that college students could accurately predict random events, like whether a computer will flash a photograph on the left or right side of its screen. However scientists and skeptics soon questioned Bem’s study and methodology. Bem stood by his findings and invited other researchers to repeat his studies.
Replication is of course the hallmark of valid scientific research—if the findings are true and accurate, they should be able to be repeated by others. Otherwise the results may simply be due to normal and expected statistical variations and errors. If other experimenters cannot get the same result using the same techniques, it’s usually a sign that the original study was flawed in one or more ways.
Last year a group of British researchers tried and failed to replicate Bem’s experiments. A team of researchers including Professor Chris French, Stuart Ritchie and Professor Richard Wiseman collaborated to accurately replicate Bem’s final experiment, and found no evidence for precognition. Their results were published in the online journal PLoS ONE.
Now a second group of scientists has also replicated Bem’s experiments, and once again found no evidence for ESP. In an article forthcoming in The Journal of Personality and Social Psychology, researchers Jeff Galak, Robyn LeBoeuf, Leif D. Nelson, and Joseph P. Simmons, the authors explained their procedure: “Across seven experiments (N = 3,289) we replicate the procedure of Experiments 8 and 9 from Bem (2011), which had originally demonstrated retroactive facilitation of recall. We failed to replicate that finding. We further conduct a meta-analysis of all replication attempts of these experiments and find that the average effect size (d = .04) is no different from zero.” In other words there was no evidence at all for ESP. The paper, “Correcting the Past: Failures to Replicate Psi,” is available on the web page of the Social Science Research Network.
MORE . . .
- Controversial ESP Study Fails Yet Again (news.discovery.com)
- ESP & Psychic Powers: Claims Inconclusive (livescience.com)
- ESP evidence fails key test of repeatability (newscientist.com)
- Controversial Psychic Ability Claim Doesn’t Hold up in New Experiments (illuminutti.com)
- The Secrets Behind the Latest ESP Research (psychologytoday.com)