What does a null hypothesis typically state?

A null hypothesis typically states that there is no difference or effect in the population being studied. This serves as a default position that suggests any observed differences in a sample are due to random chance rather than true effects. By asserting that there is no difference between groups, the null hypothesis provides a benchmark against which alternative hypotheses can be tested. If researchers find sufficient evidence against the null hypothesis, they may reject it in favor of the alternative hypothesis, which proposes that a significant difference or effect does exist. This framework is foundational in statistical testing and allows researchers to make objective conclusions based on their data.