Reproducibility of Experiments
Reproducibility is one of the main principles of the scientific method, and refers to the ability of a test or experiment to be accurately reproduced, or replicated, by someone else working independently. This is especially so in an era when scientific fraud is more widespread than ever, and research projects might have budgets of millions of dollars.
The results of an experiment performed by a particular researcher or group of researchers are generally evaluated by other independent researchers who repeat the same experiment themselves,. Then they see if their experiment gives similar results to those reported by the original group.
Reproducibility is different from repeatability, which measures the success rate in successive experiments, possibly conducted by the same experimenters. Obviously experiments are subject to experimental error, and some experiments give results which are nothing more than success percentage rates, which are also subject to experimental error and so will vary from experiment to experiment. Reproducibility relates to the consistency of test results with different operators, test apparatus, and laboratory locations, within the limits of these experimental erros.
While repeatability of scientific experiments is desirable, it is not considered necessary to establish the scientific validity of a theory. For example, the cloning of animals is difficult to repeat, but has been reproduced by various teams working independently, and is a well established research domain. One failed cloning does not mean that the theory is wrong or unscientific. Repeatability is often low in protosciences.
The basic idea can be seen in Aristotle's dictum that there is no scientific knowledge of the individual, where the word used for individual in Greek had the connotation of the idiosyncratic, or wholly isolated occurrence. Thus all knowledge, all science, necessarily involves the formation of general concepts and the invocation of their corresponding symbols in language.
In March 1989, University of Utah chemists Stanley Pons and Martin Fleischmann reported the production of excess heat that could only be explained by a nuclear process ("cold fusion"). The report was astounding given the simplicity of the equipment: it was essentially an electrolysis cell containing heavy water and a palladium cathode which rapidly absorbed the deuterium produced during electrolysis. The news media reported on the experiments widely, and it was a front-page item on many newspapers around the world. Experiments to reproduce the experiment were unsuccessful.