lucky successes to continue testing. He thought that the common null hypothesis (of no result) would not be reported, but "[e]ventually, one experimenter remains whose subject has made high scores for six or seven successive sessions. Neither experimenter nor subject is aware of the other ninety-nine projects, and so both have a strong delusion that ESP is operating." He concludes: "The experimenter writes an enthusiastic paper, sends it to Rhine who publishes it in his magazine, and the readers are greatly impressed." If sufficiently many scientists study a phenomenon, some will find statistically significant results by chance, and these are the experiments submitted for publication. Additionally, papers showing positive results may be more appealing to editors. This problem is known as positive results bias, a type of publication bias. To combat this, some editors now call for the submission of "negative" scientific findings, where "nothing happened". Survivorship bias is one of the research issues brought up in the provocative 2005 paper "Why Most Published Research Findings Are False", which shows that a large number of published medical research papers contain results that cannot be replicated. One famous example of immortal time bias was discovered in a study by Redelmeier and Singh in the Annals of Internal Medicine that reported that Academy Award-winning actors and actresses lived almost four years longer than their less successful peers. The statistical method used to derive this statistically significant difference gave winners an unfair advantage, however, because it credited an Academy Award winner's years of life before winning toward survival subsequent to winning. When the data was reanalyzed using methods that avoided this "immortal time" bias, the survival advantage was closer to one year and was not statistically significant. Examples Business, finance, and economics In finance, survivorship bias is the tendency for failed companies to be excluded from performance studies because they no longer exist. It often causes the results of studies to skew higher because only companies that were successful enough to survive until the end of the period are included. For example, a mutual fund company's selection of funds today will include only those that are successful now. Many losing funds are closed and merged into other funds to hide poor performance. In theory, 70% of extant funds could truthfully claim to have performance in the first quartile of their peers, if the peer group includes funds that have closed. In 1996, Elton,