Let's say I flipped a coin a million times. Now lets assume multiple witnesses saw me flip the coin so that heads came up twice in a row. There may be hundreds of such reports. Maybe even thousands. Would you conclude from that group of reports that I can, on demand, always flip the coin so that it comes up heads twice in a row? Or even that every time I flip the coin it comes up heads? Before taking a group of reports as evidence, keep in mind that this is selection bias.