Null hypothesis ($H_0$)

The null hypothesis is a fundamental concept in statistics and hypothesis testing. It is a statement that asserts there is no effect or no difference in a given situation, and it serves as a default or starting position for statistical analysis. The null hypothesis is usually denoted as \( H_0 \). For example, in a clinical trial, the null hypothesis might state that a new medication has no effect on patients compared to a placebo.