What does the null hypothesis state regarding the outcomes of an experiment?

The null hypothesis is a fundamental concept in statistical hypothesis testing, stating that any observed effects or differences in an experiment are due to random chance rather than any specific cause or intervention. When researchers formulate the null hypothesis, it serves as a baseline assumption, indicating that there is no effect, no difference, or no relationship between variables being studied. By establishing this baseline, researchers can then use statistical methods to determine whether the evidence gathered from their experiment provides sufficient support to reject the null hypothesis.

When results from an experiment are evaluated, if they fall within the range of what could be expected by chance alone, the null hypothesis is not rejected. Conversely, if the results indicate a statistically significant difference, researchers may find evidence against the null hypothesis, supporting the alternative hypothesis instead. This process is crucial for scientific inquiry, as it allows for objective assessment of whether observed outcomes can be attributed to experimental conditions or if they could simply be a product of random variation.