We report the results of an update to the meta-analysis by Storm, Tressoldi, and Di Risio (2010). Three laboratory-based free-response designs were assessed: (i) ganzfeld (a technique proposed to enhance a communication anomaly referred to as extra-sensory perception; ESP); (ii) nonganzfeld noise reduction using alleged ESP-enhancing techniques (e.g., dreaming, hypnosis, relaxation, and meditation); and (iii) standard free-response (nonganzfeld; non-noise-reduction). For the period 2009 to 2018, a dataset of nine new ganzfeld studies (Category 1) yielded a mean effect size (ES) of 0.119 (where ES = z/√n); 19 new nonganzfeld noise-reduction studies (Category 2) yielded mean ES = 0.045; and 15 new standard free-response studies (Category 3) yielded mean ES = 0.050. Stouffer Z scores for all three databases were significant, but each new database was not significantly different from its respective database in Storm et al. (2010). The increased ganzfeld database (N = 38) yielded a mean ES = 0.133; the nonganzfeld noise-reduction database (N = 37) yielded mean ES = 0.072; and the standard free-response database (N = 33) yielded mean ES = 0.027. Again, Stouffer Z scores were significant. We found Category 1 had a significantly higher mean effect than Category 3, and participants who were selected for the studies (they believed in psi, or practiced, say, meditation, etc.) produced a stronger mean effect than unselected (randomly assigned) participants, but there were no differences between type of modality tested (i.e., telepathy, clairvoyance, precognition), types of target (film clips, photographs, etc.), or experimenter/laboratory. There was also no evidence of a decline effect across a 44-year period. Finally, we conducted a Bayesian analysis and found that the case for a communication anomaly using free-response designs was upheld.
Noise Reduction Model of Blasting Seismic Wave Signal