What does a null hypothesis state in research?

The null hypothesis is a fundamental concept in statistical hypothesis testing, and it specifically posits that there is no effect or relationship between the variables being studied. This means that any observed differences or relationships in the data are attributed to random chance rather than a true effect or association.

When researchers formulate a null hypothesis, they aim to establish a baseline or a point of comparison for testing the effects of an independent variable on a dependent variable. If the evidence from the data is strong enough to reject the null hypothesis, the researchers can conclude that a significant effect likely exists.

Understanding the null hypothesis is crucial because it forms the foundation for statistical tests that determine whether to accept or reject it based on sample data. The other options suggest the presence of effects or relationships, or state that results are inconclusive, which are contrary to the definition and purpose of the null hypothesis.